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The first issue is scheduled to be published in Dec. 2018.

Call for Papers

CCS Chemistry is the flagship general journal for the cutting edge and fundamental research in the areas of chemica research facing global audiences published by Chinese Chemical Society. We call for excellent papers cover but not limited to synthetic chemistry, catalysis & surface chemistry, chemical theory and mechanism, chemical metrology, materials & energy chemistry, environmental chemistry, chemical biology, chemical engineering and industrial chemistry. Professional arrangement ensures that all papers can be reviewed and published online quickly and efficiently (one or two weeks).

Contact information:

Dr. Hao Linxiao,  haolinxiao@iccas.ac.cn;  +86-10-82449177-888

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Perspective
New techniques and strategies in drug discovery
Du Jintong , Guo Jing , Kang Dongwei , Li Zhihong , Wang Guan , Wu Jianbing , Zhang Zhen , Fang Hao , Hou Xuben , Huang Zhangjian , Li Guobo , Lu Xiaoyun , Liu Xinyong , Ouyang Liang , Rao Li , Zhan Peng , Zhang Xiaojin , Zhang Yihua
2020, 31(7): 1695-1708  doi: 10.1016/j.cclet.2020.03.028
[Abstract](18) [FullText HTML] [PDF 9702KB](0)
Abstract:
Great success has been witnessed in last decades, some new techniques and strategies have been widely used in drug discovery. In this roadmap, several representative techniques and strategies are highlighted to show recent advances in this filed. (A) A DOX protocol has been developed for accurate protein-ligand binding structure prediction, in which first principle method was used to rank the binding poses. Validation against crystal structures have found that DOX prediction achieved an impressive success rate of 99%, indicating significant improvement over molecular docking method. (B) Virtual target profiling is a compound-centric strategy enabling a parallel implementation of interrogating compounds against various targets in a single screen, which has been used in hit/lead identification, drug repositioning, and mechanism-of-action studies. Current and emerging methods for virtual target profiling are briefly summarized herein. (C) Research on targeted autophagy to treat diseases has received encouraging progress. However, due to the complexity of autophagy and disease, experimental and in silico methods should be performed synergistically for the entire process. This part focuses on in silico methods in autophagy research to promote their use in medicinal research. (D) Histone deacetylases (HDACs) play important roles in various biological functions through the deacetylation of lysine residues. Recent studies demonstrated that HDACs, which possess low deacetylase activities, exhibited more efficient defatty-acylase activities. Here, we review the defatty-acylase activity of HDACs and describe examples for the design of isoform selective HDAC inhibitor. (E) The FDA approval of three kinase allosteric inhibitors and some others entering clinical study has spurred considerable interests in this targeted drug discovery area. (F) Recent advances are reviewed in structure-based design of novel antiviral agents to combat drug resistance. (G) Since nitric oxide (NO) exerts anticancer activity depending on its concentration, optimal levels of NO in cancer cells is desirable. In this minireview, we briefly describe recent advances in the research of NO-based anticancer agents by our group and present some opinions on the future development of these agents. (H) The field of photoactivation strategies have been extensively developed for controlling chemical and biological processes with light. This review will summarize and provide insight into recent research advances in the understanding of photoactivatable molecules including photoactivatable caged prodrugs and photoswitchable molecules.
Review
Recent progress in tumor photodynamic immunotherapy
Shen Lijun , Zhou Tianjiao , Fan Yatong , Chang Xin , Wang Yi , Sun Jianguo , Xing Lei , Jiang Hulin
2020, 31(7): 1709-1716  doi: 10.1016/j.cclet.2020.02.007
[Abstract](20) [FullText HTML] [PDF 3460KB](0)
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Photodynamic therapy (PDT) is a promising alternative approach for effective cancer treatment, which can directly destroy local tumor cells due to the generation of cytotoxic singlet oxygen and reactive oxygen species (ROS) in the tumor cells. Intriguingly, PDT-mediated cell death is also associated with anti-tumor immune response. However, immunosuppression of tumor microenvironment is able to limit the immune response induced by PDT, it is therefore necessary to combine with immunocheckpoint inhibitor and immunoadjuvant for synergistic treatment of tumors. Herein, the recent advances of PDT, immunotherapy, and photodynamic immunotherapy are reviewed.
Ag2S nanoparticles as an emerging single-component theranostic agent
Han Ruxia , Peng Jinrong , Xiao Yao , Hao Ying , Jia Yanpeng , Qian Zhiyong
2020, 31(7): 1717-1728  doi: 10.1016/j.cclet.2020.03.038
[Abstract](17) [FullText HTML] [PDF 10595KB](0)
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Last two decades, with the rapid changes and development of nanotechnology and biological materials, diverse multi-functional nanomaterials emerging, which offers a novel way to treat and diagnose diseases, and therefore spawned the new biomedical technology of theranostics, which integrates the treatment and diagnosis or monitoring of diseases into one. Ag2S as a bio-nanomaterial with low biotoxicity has attracted more and more attention due to its good photoluminescence properties and fluorescence imaging of small animals in the second near-infrared region (NIR-II). Meanwhile, Ag2S has the ability to absorb near-infrared light strongly because of its local surface plasma resonance (LSPR) effect and had become a kind of photothermal converters with good photothermal conversion efficiency. More interestingly, both photothermal effect and fluorescence characteristics of Ag2S nanoparticles (NPs) are closely related to their particle sizes. However, the relationship between photothermal effect and fluorescence characteristics of Ag2S NPs and their sizes has not been reviewed so far. Herein, the synthesis methods and influencing factors of synthesize Ag2S NPs with different sizes were compared firstly, and then the photothermal effect and fluorescence characteristics of Ag2S NPs with different sizes were summarized. Finally, the possibilities and challenges of using Ag2S NPs to construct theranostic agent were discussed in the end.
The application of biomacromolecules to improve oral absorption by enhanced intestinal permeability: A mini-review
Sun Min , Hu Hankun , Sun Leming , Fan Zhen
2020, 31(7): 1729-1736  doi: 10.1016/j.cclet.2020.02.035
[Abstract](15) [FullText HTML] [PDF 5718KB](0)
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Oral administration has been widely regarded as the most convenient, quick and safe approach compared to other routes of drug delivery. However, oral absorption of drugs is often limited due to rigorous environments and complex obstacles in gastrointestinal tract. Having received considerable attention, biomacromolecules have been applied for oral drug delivery to improve the bioavailability, which could be attributed to its stability and unique bioactivities, including intestinal adhesion, opening of epithelial tight junctions, inhibiting cell efflux and regulating relative protein expression. Specifically, enhancing intestinal permeability has been regarded as a promising strategy for improving bioavailability of oral drug delivery. In this review, a series of biomacromolecules and the related mechanisms of increasing intestinal permeability for enhanced oral bioavailability are comprehensively classified and elucidated. In addition, recent advances in biomacromolecules based oral delivery and related future directions are mentioned and predicted in this review article.
Extracellular vesicles based electrochemical biosensors for detection of cancer cells: A review
Xie Hui , Di Kaili , Huang Rongrong , Khan Adeel , Xia Yanyan , Xu Hongpan , Liu Chang , Tan Tingting , Tian Xinyu , Shen Han , He Nongyue , Li Zhiyang
2020, 31(7): 1737-1745  doi: 10.1016/j.cclet.2020.02.049
[Abstract](16) [FullText HTML] [PDF 8109KB](0)
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Extracellular vesicles (EVs) derived from cancer cells are considered as ideal biomarker for liquid biopsy in cancer diagnosis, and are stable and abundant. Electrochemical methods for the detection of EVs are preferred over conventional methods such as Western blotting and enzyme-linked immunosorbent assay for their high sensitivity and real-time detection. This article summaries studies proposing the electrochemical methods utilizing immunological and molecular methodologies for detecting EVs derived biomacromolecules such as miRNAs and transmembrane protein for cancer diagnosis. Moreover, the electrochemical detection methods are compared and future prospects for the development of electrochemical methods for EVs detection are concluded.
A review of linear carbon chains
Zhang Kan , Zhang Yifan , Shi Lei
2020, 31(7): 1746-1756  doi: 10.1016/j.cclet.2020.03.019
[Abstract](11) [FullText HTML] [PDF 4821KB](0)
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Linear carbon chains (LCCs) are a one-dimensional sp1-hybridized allotrope of carbon. LCCs are extremely unstable: The longer the LCCs, the less stable the materials. Thus, it is a big challenge to synthesize long LCCs. Although the research on the short LCCs, e.g., polyynes, can be traced back to the 18th, LCCs are still not well-known compared to other allotropes of carbon, e.g., fullerenes, carbon nanotubes and graphene. Therefore, introducing recent progress on LCCs is of great significance to draw more attention in the community of nanocarbons as well as nanomaterials in general. Theoretically, various excellent properties have been predicted. Experimentally, LCCs with different length in many kinds of forms have been successfully synthesized. In this review, we summarized recent studies of polyynic LCCs from both theoretical and experimental aspects. Also, perspectives are highlighted to point out the further investigations of the materials.
Viologen derivatives with extended π-conjugation structures: From supra-/molecular building blocks to organic porous materials
Zhou Xiao-He , Fan Yu , Li Wan-Xia , Zhang Xiang , Liang Rong-Ran , Lin Feng , Zhan Tian-Guang , Cui Jiecheng , Liu Li-Juan , Zhao Xin , Zhang Kang-Da
2020, 31(7): 1757-1767  doi: 10.1016/j.cclet.2019.12.039
[Abstract](13) [FullText HTML] [PDF 16803KB](0)
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Recently, increasing attention has been paid on extending the π-conjugation structures of viologens (1, 1'-disubstituted-4, 4'-bipyridylium salts) by incorporating planar aromatic units into the bipyridinium backbones. Various viologen derivatives with extended π-conjugation structures have been synthesized, including the N-termini aromatic substituted viologens, the extended π-conjugated viologens (denoted as ECVs) as well as the π-conjugated oligomeric viologens (denoted as COVs). These compounds typically exhibit interesting properties distinguished from those of an isolated viologen unit, which make them as new class of electron deficient supra-/molecular building blocks in supramolecular chemistry and materials science. In this review, we would like to highlight the recent advances of viologen derivatives with extended π-conjugation structures in versatile applications ranging from electrochromic and energy storage materials, the ECV/COV-based supramolecular self-assembly systems including the linear supramolecular polymers and 2D/3D supramolecular organic frameworks (SOFs), to the viologen-based covalent organic frameworks (COFs)/networks. We hope this review will serve as an in-time summary worthy of referring, more importantly, to provide inspiration in the rational design of novel molecules with unexplored properties and functions.
The application of metal-organic frameworks in electrocatalytic nitrogen reduction
Wang Yihang , Li Qiang , Shi Wei , Cheng Peng
2020, 31(7): 1768-1772  doi: 10.1016/j.cclet.2020.01.010
[Abstract](13) [FullText HTML] [PDF 4603KB](0)
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In recent years, the research of nitrogen reduction reaction (NRR) under ambient conditions has attracted wide attention for their relatively low energy consumption, in which rational design of electrocatalysts is the key to achieve high-performance NRR. Metal-organic frameworks (MOFs), as a new kind of porous material, have been intensively studied in the past few decades owing to not only their structural versatility and tunability but also intrinsic porosity. Due to their structural features, MOFs also have potential applications in mild condition electrocatalysis of NRR. In this review, the recently experimental and theoretical studies of MOFs in NRR electrocatalysts are briefly summarized.
A review on metal-organic frameworks for photoelectrocatalytic applications
Mu Feihu , Dai Benlin , Zhao Wei , Zhang Lili , Xu Jiming , Guo Xujing
2020, 31(7): 1773-1781  doi: 10.1016/j.cclet.2019.12.015
[Abstract](17) [FullText HTML] [PDF 3529KB](0)
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Semiconductor-based photoelectrocatalytic processes have attracted considerable research interest for solar energy collection and storage. Photoelectrocatalysis is a heterogeneous photocatalytic process in which a bias potential is applied to a photoelectrode, and thus the photoelectrocatalytic performance is closely related to the photoelectrode prepared by semiconductors. Among various semiconductors, metal-organic frameworks (MOFs) have attracted more and more attention because of their unique properties such as optical properties and adjustable structure. Herein, a comprehensive review on different MOFs (Ti-based, Zn-based, Co-based, Fe-based, Cu-based, and mixed metal-based MOFs) for heterogeneous photoelectrocatalysis is carried out and, in particular, the application of this technique for CO2 conversion and water splitting is discussed. In addition, the challenges and development prospects of MOFs in photoelectrocatalysis are also presented.
Communication
Blocking the defect sites on ultrathin Pt nanowires with Rh atoms to optimize the reaction path toward alcohol fuel oxidation
Zhao Xiaoyu , Zhao Huachao , Sun Jiefang , Li Gang , Liu Rui
2020, 31(7): 1782-1786  doi: 10.1016/j.cclet.2020.01.005
[Abstract](13) [FullText HTML] [PDF 5651KB](0)
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Anodic electrocatalyst plays the core role in direct alcohol fuel cells (DAFCs), while traditional Pt-catalysts suffer from limited catalytic activity, high over potential and severe CO poisoning. Herein, by selectively depositing Rh atoms on the defective-sites of Pt nanowires (NWs), we developed a new Pt@Rh NW electrocatalyst that exhibited enhanced electrocatalytic performance for both methanol oxidation (MOR) and ethanol oxidation (EOR). Both cyclic voltammetry (CV) and in-situ infrared spectroscopy revealed that the presence of Rh atoms suppressed the generation of poisonous intermediates and completely oxidized alcohols molecule into CO2. Atomic resolusion spherical aberration corrected high-angle annular dark field scanning transmission electron microscopy (CS-HAADF-STEM) and energy-dispersive X-ray spectroscopy (EDS) mapping analysis revealed that Rh atoms were primarily deposited on the defective sites of Pt NWs. Meanwhile, the presence of Rh atoms also modified the electronic state of Pt atoms and therefore lowered the onset potential for alcohols oxidation potential. This work gives the first clear clue on the role of the defective sites of Pt nanocatalyst poisoning, and propose that selectively blocking these sites with trace amount of Rh is an effective strategy in designing advantageous electrocatalysts.
Transformable peptide nanoparticles inhibit the migration of N-cadherin overexpressed cancer cells
Fan Jiaqi , Fan Yu , Wei Zijin , Li Yijing , Li Xiangdan , Wang Lei , Wang Hao
2020, 31(7): 1787-1791  doi: 10.1016/j.cclet.2020.03.065
[Abstract](14) [FullText HTML] [PDF 15381KB](0)
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About 90% cancer-related mortality results from the cancer metastasis, which generally undergoes after epithelial-mesenchymal transition (EMT) process. N-Cadherin, overexpressed on cancer cell surface during EMT, can enhance the migration of cancer cells. Herein, we design and synthesize a transformable peptide BP-KLVFF-SWTLYTPSGQSK (BFS) that can block N-cadherin for inhibiting cancer migration and metastasis. The peptide BFS consists of three modules including (1) the hydrophobic bis-pyrene (BP) unit for forming and locating nanoparticles, (2) the KLVFF peptide sequence for forming and stabilizing fibrous structures and (3) the targeting peptide sequence SWTLYTPSGQSK that can specifically bind to Ncadherin. The peptide BFS can form nanoparticles in PBS, which can transform to nanofibers when targeting and binding to N-cadherin. The nanofibers inhibit the migration of N-cadherin overexpressed MDA-MB-436 cancer cells. The peptide BFS shows 83.6% inhibiting rate in cells wound healing assay. In addition, the inhibition rate is 67.9% when the BFS applied in transwell migration assay. These results indicate that the BFS has excellent ability to inhibit migration of cancer cells. This self-assembly strategy could be potentially utilized to regulate the key protein during EMT for inhibiting the tumor metastasis.
Smart nanoprobe based on two-photon sensitized terbium-carbon dots for dual-mode fluorescence thermometer and antibacterial
Yan Huicheng , Ni Hongyuhang , Yang Yiwei , Shan Changfu , Yang Xiaoxi , Li Xiangkai , Cao Jing , Wu Wenyu , Liu Weisheng , Tang Yu
2020, 31(7): 1792-1796  doi: 10.1016/j.cclet.2019.12.022
[Abstract](13) [FullText HTML] [PDF 3650KB](0)
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Accurate temperature measurement plays an important role in a variety of industrial processes and scientific researches. In our work, the dual-mode temperature response nanoprobe CDs-Tb-TMPDPA containing a two-photon ligand (4-(2, 4, 6-trimethoxyphenyl)-pyridine-2, 6-dicarboxylic acid, TMPDPA) sensitized Tb3+ as a temperature-sensitive unit and carbon dots (CDs) as photothermal reagent and a fluorescence reference unit, have been designed and synthesized. In this system, both the fluorescence intensity ratio and the fluorescence lifetime have a good response to temperature. In addition, due to the excellent photothermal conversion capability of CDs, photothermal antibacterial ability was also tested. Based on the temperature dependence of the fluorescence and the two-photon excitation characteristics of CDs-Tb-TMPDPA, the nanoprobe can also be used in the anti-counterfeiting. Our finding opens a new prospect for the use of two-photon sensitized dual-mode fluorescence thermometers.
3D porous acellular cartilage matrix scaffold with surface mediated sustainable release of TGF-β3 for cartilage engineering
Huang Yixing , Yu Xingfang , He Linjie , Liao Xin , Wang Shuo , Qian Zhiyong , Shen Liyan
2020, 31(7): 1797-1800  doi: 10.1016/j.cclet.2020.01.039
[Abstract](14) [FullText HTML] [PDF 4688KB](0)
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Acellular tissue matrix scaffolds are much closer to tissue's complex natural structure and biological characteristics, thus assess great advantages in cartilage engineering. We used rabbit costal cartilage to prepare acellular microfilaments and further 3D porous acellular cartilage scaffold via crosslinking. Poly (L-lysine)/hyaluronic acid (PLL/HA) multilayer film was then built up onto the surface of the resulting porous scaffold. Furthermore, TGF-β3 was loaded into the PLL/HA multilayer film coated scaffold to obtain a 3D porous acellular cartilage scaffold with sustained releasing of TGF-β3 up to 60 days. The success of this project will provide a new way for the treatment of articular cartilage defects. Meanwhile, the anchoring and on-site sustained releasing of growth factors mediated by polyelectrolyte multilayered film can also provide a new method for improving the biocompatibility and the biofunctionality for other implanted biomaterials.
Dual-functional Se/Fe complex facilitates TRAIL treatment against resistant tumor cells via modulating cellular endoplasmic reticulum stress
Yang Yahui , Wang Yifan , Xu Ligeng , Chen Tianfeng
2020, 31(7): 1801-1806  doi: 10.1016/j.cclet.2020.03.004
[Abstract](19) [FullText HTML] [PDF 7094KB](0)
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Tumor cell resistance is one of the big hurdles limiting the therapeutic efficacy of tumor necrosis factorrelated apoptosis-inducing ligand (TRAIL)-based cancer treatment. Therefore, the development of a safe and effective sensitizer agent is greatly desired for optimizing TRAIL therapy. Herein, we successfully developed a Se/Fe complex with low toxicity to highly effectively inhibit tumor cells proliferation and migration capabilities through down-regulating ER stress related selenoproteins. Furthermore, it could more efficiently damage tumor spheroids with good penetration capability. More importantly, it could synergize with TRAIL treatment to induce the robust generation of reactive oxygen species (ROS), downregulating ER stress related selenoproteins for triggering tumor cells apoptosis in extrinsic and intrinsic signaling pathways. Taken together, this study provides a potential chemo-drug and sensitizer agent to improve the therapeutic efficacy of TRAIL-based cancer treatment.
Anti-inflammatory catecholic chitosan hydrogel for rapid surgical trauma healing and subsequent prevention of tumor recurrence
He Gang , Yan Xu , Miao Zhaohua , Qian Haisheng , Ma Yan , Xu Yan , Gao Li , Lu Yang , Zha Zhengbao
2020, 31(7): 1807-1811  doi: 10.1016/j.cclet.2020.02.032
[Abstract](18) [FullText HTML] [PDF 6757KB](0)
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Although occupying pillar position in clinical cancer treatments, surgery itself and surgical trauma would elicit series of local/systemic inflammation-related responses that resulted in high rate of tumor recurrence. Herein, chitosan with conjugated gallic acid (CSG) molecules were coordinated with Fe3+ to form CSG/Fe3+ hydrogel for filling the tumor-resected cavity with considerable wet-adhesion ability and anti-inflammatory performance. With the assistance of doxorubicin hydrochloride (DOX·HCl), CSG/Fe3+/DOX hydrogel exhibited synergistic photothermal-chemo tumor-inhibited performance under near-infrared (NIR) light irradiation for eradicating residual and/or surgical trauma-recruited cancer cells. Thus, our study attempts to show a paradigm that realizes quick surgical trauma healing, inflammation inhibition and prevention of postsurgical tumor recurrence.
Rapid identification of diarrheagenic Escherichia coli based on barcoded magnetic bead hybridization
Dong Hongming , Tang Congli , He Ziyu , Liu Hongmei , Xu Yuyue , Huang Hao , Yang Gaojian , Xiao Ziqi , Li Song , Deng Yan , Chen Zhu , Chen Hui , Qin Zuodong , Negrin Yasser Perera , He Nongyue
2020, 31(7): 1812-1816  doi: 10.1016/j.cclet.2020.03.002
[Abstract](20) [FullText HTML] [PDF 2883KB](0)
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Diarrhea, as a global public health problem, causes a large number of infections and deaths every year. Although Escherichia coli (E. coli) is one of the normal flora microorganisms in the human intestinal tract, it has five pathogenic bacteria types that can cause human diarrhea, known as diarrheagenic E. coli. When people are infected, rapid and accurate diagnosis, along with timely treatment, are especially important. Here, we introduce a new method to identify and analyze a large number of pathogenic strains in E. coli by multiplex PCR and barcoded magnetic bead hybridization. Results show that the detection sensitivities of enterohemorrhagic E. coli, enterotoxigenic E. coli, enteropathogenic E. coli, enteroinvasive E. coli and enteroaggregative E. coli were 1.3×103 CFU/mL, 2×104 CFU/mL, 4×104 CFU/mL, 7.2×104 CFU/mL and 1.7 CFU/mL respectively. This method has strong specificity and high sensitivity and detects multiple target sequences in one experiment. Compared with other methods, BMB array has great application potential.
Injectable baicalin/F127 hydrogel with antioxidant activity for enhanced wound healing
Liu Guiting , Bao Ziting , Wu Jun
2020, 31(7): 1817-1821  doi: 10.1016/j.cclet.2020.03.005
[Abstract](122) [FullText HTML] [PDF 5877KB](0)
Abstract:
Baicalin, extracted from traditional Chinese medicine Scutellaria baicalensis Georg, possesses multiple pharmacological activities and has great potential for chronic skin wound repair. However, the poor solubility and lack of suitable vehicles greatly limit its further application. Herein, we proposed a convenient and robust strategy, employing PBS solution as solvent, to enhance the solubility of baicalin. Furthermore, we constructed injectable baicalin/F127 hydrogels to study their application in skin wound treatment. The composition and temperature sensitivity of baicalin/Pluronic® F-127 hydrogels were confirmed by FTIR and rheological testing, respectively. In vitro release measurement indicated that the first order model was best fitted with the release profile of baicalin from hydrogel matrix. Besides, MTT assay, AO/EO staining assay as well as hemolytic activity test revealed the excellent cytocompatibility of baicalin/F127 hydrogels. Antioxidant activity assay demonstrated the cytoprotective activity of baicalin/ F127 hydrogels against reactive oxygen species (ROS). Furthermore, the in vivo experiments exhibited the ability of baicalin/F127 hydrogel to accelerate wound healing. In conclusion, this novel injectable baicalin/F127 hydrogel should have bright application for chronic wound treatment.
Hyperbranched polymer micelles with triple-stimuli backbone-breakable iminoboronate ester linkages
Zhang Xuan , Gao Jushan , Zhao Xiaoye , Liu Zhaotie , Liu Zhongwen , Wang Ke , Li Guo , Jiang Jinqiang
2020, 31(7): 1822-1826  doi: 10.1016/j.cclet.2020.03.018
[Abstract](15) [FullText HTML] [PDF 6006KB](0)
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Hyperbranched polymers have attracted increasing interests due to their unique structure-related advantages and have been utilized as drug carriers for controlled delivery. However, it is still challenging to prepare multi stimuli-responsive hyperbranched polymers to sense and response the complex yet delicate changes in physiological environment. Herein, we propose a triple-stimuli backbone-breakable hyperbranched polymer (HBP(OEG-IB)), which is prepared via the convenient iminoboronate multicomponent reaction of α, w-di(1, 2-diol)s oligo(ethylene glycol), tris(3-aminopropyl)amine and 2-formylphenylboronic acid. Upon the stimulation of CO2, lactic acid and glutathione, micelles formed by HBP(OEG-IB) could be disrupted via the dissociation of iminoboronate ester bond to subsequent release incorporated camptothecin (CPT). Cell experiments show that the HBP(OEG-IB) is non-toxic but can enhance the therapeutic effect of CPT thanks to the effect of the protonated tertiary amino groups. The demonstration made in this work can enrich the design of responsive HBPs and can be readily applied to other systems with tunable responsive properties and functions.
Development and validation of an improved probabilistic quotient normalization method for LC/MS- and NMR-based metabonomic analysis
An Yanpeng , Liu Si , Hao Fuhua , Wang Yulan , Tang Huiru
2020, 31(7): 1827-1830  doi: 10.1016/j.cclet.2019.12.011
[Abstract](17) [FullText HTML] [PDF 2454KB](0)
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Robust normalization is a prerequisite for reliable metabonomic analysis especially when intervention treatments cause drastic metabolomic changes or when spot urinary samples are employed without knowing the drinking water quantity. With the simulated and real datasets, here, we report a probabilistic quotient normalization method based on the mode-of-quotients (mPQN) which is suitable for metabonomic analysis of both NMR and LC-MS data with little and/or drastic metabolite changes. When applied to metabonomic analysis of both animal plasma samples and human urinary samples, this newly proposed method has clearly shown better robustness than all classical normalization methods especially when drastic changes of some metabolites occur.
Cholesterol as a functional metabolite cooperates with metadherin in cancer cells
Wang Wen , Liu Xiaolong , Chen Huan , Ling Ting , Xia Tian , Liu Xiumei , Liu Jing , Otkur Wuxiyar , Shi Xianzhe , Qi Huan , Chen Di , Piao Hai-Long
2020, 31(7): 1831-1834  doi: 10.1016/j.cclet.2019.12.027
[Abstract](13) [FullText HTML] [PDF 3683KB](0)
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Protein-metabolite interactions (PMIs) play important roles in various biological processes, especially in disease progression. However, due to the complexity of living cells, it is very difficult to identify specific PMIs. Herein, we chose one oncogenic factor, metadherin (MTDH), as a bait to identify its in vivo interacting metabolites in cancer cells. Cholesterol is an important metabolite and essential structural component of cell membranes. It could also drive several diseases including cancer. Interestingly, we found that cholesterol robustly interacted with MTDH and downregulated the expression of MTDH in cancer cells. Furthermore, MTDH disturbed metabolite alterations under cholesterol treatment in MTDH transduced cancer cells. Collectively, our results uncover an undescribed PMI where MTDH, as an oncogenic factor, might positively regulate cancer progression by interacting with cholesterol. This study interprets the theoretical basis of PMI-oriented cancer progression and targeting therapies in clinic.
An immunoassay based on lab-on-a-chip for simultaneous and sensitive detection of clenbuterol and ractopamine
Wang Qi , Deng Jinqi , Chen Yiping , Luo Yunjing , Jiang Xingyu
2020, 31(7): 1835-1838  doi: 10.1016/j.cclet.2020.01.028
[Abstract](13) [FullText HTML] [PDF 2194KB](0)
Abstract:
Both clenbuterol (CLB) and ractopamine (RAC) are β-adrenergic agonists. After long-term excessive intake, there will be adverse reactions such as headache, chest tightness, limb numbness, and serious lifethreatening. Simultaneous detection of CLB and RAC in related samples is of great importance for human health. In this work, we outline a microfluidics-based indirect competitive immunoassay (MICI) system that can sensitively detect residual CLB and RAC in pork, swine blood and swine urine. The rapid detection of multiple samples can be achieved in one chip, which greatly improves the detection efficiency. This method has good stability and reproducibility and the microfluidic chips are easy to manufacture. The linear ranges for CLB and RAC detection by MICI are 0.1-2.5 ng/mL and 0.1-5 ng/mL, and the limits of detection (LODs) are 0.094 ng/mL and 0.091 ng/mL, respectively. This straightforward and portable immunoassay system provides a good platform for rapid detection of harmful substances in food samples.
Study of the effect of chemical composition on the surface wettability of three-dimensional graphene foams
Huang Guihua , Song Xinhong , Chen Yiying , Lin Fangyuan , Huang Yipeng , Li Feiming , Guo Zhiyong , Yao Qiuhong , Chen Xi
2020, 31(7): 1839-1842  doi: 10.1016/j.cclet.2020.02.053
[Abstract](15) [FullText HTML] [PDF 2217KB](0)
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The chemical composition obviously affects the surface wettability of a three-dimensional (3D) graphene material apart from its surface energy and microstructure. In the hydrothermal preparation, the heteroatom doping changes the chemical composition and wettability of the 3D graphene material. To realize the controllable surface wettability of graphene materials, aminobenzene sulfonic acid (ABSA) was selected as a typical doping agent for the preparation of nitrogen and sulfur co-doped 3D graphene foam (SNGF) using a hydrothermal method. Different from using o-ABSA or p-ABSA as the dopant, SNGF with tunable surface wettability is obtained only when m-ABSA is used. This result indicates that the substituent position of -SO3H group in the benzene ring of ABSA is rather important for the tunable wettability. This work provides some theoretical foundations for dopant selection and some new insights in manipulating the properties of 3D graphene foams by adjusting the configuration of dopants.
Sulfonic acid-based metal organic framework functionalized magnetic nanocomposite combined with gas chromatography-electron capture detector for extraction and determination of organochlorine
Wang Ying , Ye Qing , Yu Menghuan , Zhang Xijun , Deng Chunhui
2020, 31(7): 1843-1846  doi: 10.1016/j.cclet.2020.02.054
[Abstract](47) [FullText HTML] [PDF 1433KB](0)
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The metal organic framework functionalized with sulfonic acid was combined with magnetic nanoparticles to fabricate a new nanocomposite (denoted as Fe3O4@PDA@Zr-SO3H). By combining with gas chromatography-electron capture detector, the resulting Fe3O4@PDA@Zr-SO3H nanocomposite was successfully used as a high-efficiency adsorbent for pre-concentrating eight organochlorine pesticides from water sample in environment. Apart from the ability of fast separation, the as-prepared Fe3O4@PDA@Zr-SO3H nanocomposite also exhibited high adsorption capacity for organochlorine pesticides. With the use of optimal experimental conditions, the linear relationship can be obtained in the range of 0.05~300 μg/L, the correlation coefficient was over 0.9978, and the relative standard deviation was located in 2.5%-7.7%. Moreover, the limit of detection and quantification was between 0.005-0.016 μg/L and 0.017~0.050 μg/L. Finally, the nanocomposite was used for the determination of organochlorine pesticides from environmental water samples, and displayed the recovery of 82%-118%.
Synthesis and characterization of an unexpected mechanochromicbistricyclic aromatic ene
Huo Gui-Fei , Tu Qian , Zhao Xiao-Li , Shi Xueliang , Yang Hai-Bo
2020, 31(7): 1847-1850  doi: 10.1016/j.cclet.2020.02.010
[Abstract](14) [FullText HTML] [PDF 4203KB](0)
Abstract:
An unexpected bistricyclic aromatic ene AF was synthesized in a tin(Ⅱ) chloride-mediated reductive aromatization reaction. The obtained AF showed a highly overcrowded structural conformation as revealed by X-ray crystallography. Interestingly, AF exhibited reversible high-contrast mechanochromism and thermochromism between pale and red color. The obvious chromism is likely ascribed to the conformation transformation and trace amount of diradical species formation upon stimulus.
Versatile synthesis of cadalene and iso-cadalene from himachalene mixtures: Evidence and application of unprecedented rearrangements
Ait El Had Mustapha , Oukhrib Abdelouahd , Zaki Mohamed , Urrutigoïty Martine , Benharref Ahmed , Chauvin Remi
2020, 31(7): 1851-1854  doi: 10.1016/j.cclet.2020.03.008
[Abstract](21) [FullText HTML] [PDF 1793KB](0)
Abstract:
From a mixture of α-, β- and γ-himachalenes extracted from waste wood of Atlas cedar (Cedrus atlantica), cadalene (1, 6-dimethyl-4-isopropylnaphthalene) and iso-cadalene (1, 6-dimethyl-3-isopropylnaphthalene) were produced in two steps with up to 71%±5% yield through the ar-himachalene intermediate using I2 and/or AlCl3 as reagents. The selectivity is shown to sharply depend on the operating conditions: while I2/AlCl3 in dichloromethane promotes the formation of cadalene, the formation of iso-cadalene is favored in the presence of AlCl3 in cyclohexane. The bicyclic aromatic compounds were thus obtained through unique rearrangements involving sequential C—C bond cleavage/formation and hydride transfer processes. In the absence of AlCl3 or I2, dihydrocurcumene was also found to be formed with up to 70% selectivity. A tentative mechanism is proposed and discussed.
Electrochemical synthesis of α, α-dihaloacetophenones from terminal alkyne derivatives
Li Zhibin , Sun Qi , Qian Peng , Hu Kangfei , Zha Zhenggen , Wang Zhiyong
2020, 31(7): 1855-1858  doi: 10.1016/j.cclet.2020.02.030
[Abstract](16) [FullText HTML] [PDF 1684KB](0)
Abstract:
By virtue of electrochemistry, a series of α, α-dihaloacetophenones were easily obtained with good to excellent yields. This electrochemical procedure was taken in a divided cell with constant current in aqueous media. The reaction can be carried out smoothly at room temperature under metal and oxidant free condition, which provides an eco-friendly synthesis for the α, α-dihaloacetophenone derivatives.
Facile access to chiral 4-substituted chromanes through Rh-catalyzed asymmetric hydrogenation
Lin Tao , Zhao Qingyang , Zhang Xumu , Dong Xiu-Qin
2020, 31(7): 1859-1862  doi: 10.1016/j.cclet.2020.01.001
[Abstract](12) [FullText HTML] [PDF 1868KB](0)
Abstract:
Rh/ZhaoPhos-catalyzed asymmetric hydrogenation of a series of (E)-2-(chroman-4-ylidene)acetates was successfully developed to prepare various chiral 4-substituted chromanes with high yields and excellent enantioselectivities (up to 99% yield, 98% ee). Moreover, the gram-scale hydrogenation could be performed well in the presence of 0.02 mol% catalyst loading (TON = 5000), the hydrogenation product was easily converted to access other important compounds, which demonstrated the synthetic utility of this asymmetric catalytic methodology.
Visible-light-promoted oxidative decarboxylation of arylacetic acids in air: Metal-free synthesis of aldehydes and ketones at room temperature
He Shuaiqi , Chen Xiaolan , Zeng Fanlin , Lu Peipei , Peng Yuyu , Qu Lingbo , Yu Bing
2020, 31(7): 1863-1867  doi: 10.1016/j.cclet.2019.12.031
[Abstract](14) [FullText HTML] [PDF 1978KB](0)
Abstract:
A metal-free photocatalytic oxidative decarboxylation reaction at room temperature was developed for the synthesis of aromatic aldehydes and ketones from the corresponding arylacetic acids. The reaction was realized under blue-light irradiation by adding 1 mol% of 4CzIPN as photocatalyst and air as oxidant. This reaction represents a novel decarboxylation of a sp3-hybridized carboxylic acids without traditional heating, additional oxidants, and metal reagents under mild conditions.
1, 2-Diethoxyethane catalyzed oxidative cleavage of gem-disubstituted aromatic alkenes to ketones under minimal solvent conditions
Liu Kai-Jian , Deng Ji-Hui , Zeng Tang-Yu , Chen Xin-Jie , Huang Ying , Cao Zhong , Lin Ying-Wu , He Wei-Min
2020, 31(7): 1868-1872  doi: 10.1016/j.cclet.2020.01.036
[Abstract](16) [FullText HTML] [PDF 3013KB](0)
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Aerobic oxidation using pure dioxygen gas as the oxidant has attracted much attention, but its application in synthetic chemistry has been significantly hampered by the complexity of catalytic system and potential risk of high-energy dioxygen gas. By employing 1, 2-diethoxyethane as a catalyst and ambient air as an oxidant, an efficient protocol for the construction of various aryl-alkyl and diaryl ketones through oxidative cleavage of gem-disubstituted aromatic alkenes under minimal solvent conditions has been achieved.
Inhibition of insulin fibrillation by amphiphilic sulfonatocalixarene
Zhao Hong , Yang Xiao-Hua , Pan Yu-Chen , Tian Han-Wen , Hu Xin-Yue , Guo Dong-Sheng
2020, 31(7): 1873-1876  doi: 10.1016/j.cclet.2020.01.042
[Abstract](14) [FullText HTML] [PDF 2803KB](0)
Abstract:
Insulin fibrillation poses a variety of problems in biomedical and biotechnological applications of insulin. Inhibiting insulin fibrillation is highly on demand to address those problems. We herein demonstrate the capability of amphiphilic sulfonatocalixarene to inhibit insulin fibrillation. The amphiphilic assembly of p-sulfonatocalix[4]arene tetra dodecyl ether exhibits much better efficiency on inhibiting insulin fibrillation, with respect to p-sulfonatocalix[4]arene and sodium dodecyl benzenesulphonate. The pronounced inhibition effect results from both the preorganized scaffold of calixarene and the amphiphilic assembly.
Introduction of N, N'-disulfonylhydrazines as new sulfonylating reagents for highly efficient synthesis of (E)-β-iodovinyl arenesulfones under mild conditions
Luo Dongping , Min Lin , Zheng Weiping , Shan Lidong , Wang Xinyan , Hu Yuefei
2020, 31(7): 1877-1880  doi: 10.1016/j.cclet.2019.12.040
[Abstract](12) [FullText HTML] [PDF 1832KB](0)
Abstract:
N, N'-Disulfonylhydrazines have been proven to be the most reactive precursors of the sulfonyl radicals among all types of sulfonyl substituted hydrazines as early as half a century ago. However, the sulfonyl radicals generated from these compounds have not been used in organic synthesis except the simple selfdimerization synthesis of disulfones controlled by the “solvent-cage-effects”. In this article, N, N'-disulfonylhydrazines were introduced as new sulfonylating reagents and their combinations with NIS were disclosed as new iodosulfonylating reagents of alkynes. Finally, a highly efficient method for the synthesis of (E)-β-iodovinyl arenesulfones was developed by mixing an alkyne, a N, N'-disulfonylhydrazine and NIS in aqueous THF at room temperature for 5 min.
Design and synthesis of the ring-opened derivative of 3-n-butylphthalide-ferulic acid-glucose trihybrids as potential anti-ischemic agents
Wu Jianbing , Yin Wei , Zhang Yinqiu , Ye Hui , Li Yunman , Tian Jide , Huang Zhangjian , Zhang Yihua
2020, 31(7): 1881-1886  doi: 10.1016/j.cclet.2020.02.031
[Abstract](12) [FullText HTML] [PDF 2460KB](0)
Abstract:
To improve aqueous solubility and anti-ischemic activity of 3-n-butylphthalide (NBP), we designed and synthesized the ring-opened derivative of NBP-ferulic acid-glucose trihybrids (S1-S8). These hybrids inhibited adenosine diphosphate (ADP)- or arachidonic acid (AA)-induced platelet aggregation, among them, S2 was 30-fold more water-soluble, and over 10-fold more potent in inhibition of platelet aggregation, as well as reduced ROS generation and protected primary neuronal cells from OGD/Rinduced damage, in comparison with NBP. Additionally, S2 was more active than its three moieties alone or in combination, suggesting that the activity of S2 may be attributed to the synergistic effects of these moieties. Importantly, in vivo studies indicated that S2 not only possessed good pharmacokinetic profile, but also improved NBP distribution in rodent brain, suggesting that the glucose moiety in S2 may be recognized by glucose transporter 1 (GLUT1) on blood-brain barrier (BBB), promoting it to penetrate through BBB. Our findings suggest that S2 may be a promising candidate for the intervention of ischemic stroke, warranting further study.
Synthesis of selenium-doped carbon from glucose: An efficient antibacterial material against Xcc
Cao Hongen , Yang Yufan , Chen Xijun , Liu Jian , Chen Chao , Yuan Shuzhong , Yu Lei
2020, 31(7): 1887-1889  doi: 10.1016/j.cclet.2020.01.027
[Abstract](19) [FullText HTML] [PDF 3108KB](0)
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Se/C as a novel carbon-based biomaterial was prepared by using cheap and abundant glucose as the carbon source. It was highly active and could well restrain Xanthomonas campestris pv. campestris (EC50 = 4.7403 μg/mL), a very harmful germ causing the devastating cabbage black rot disease and resulting in huge economic losses. As a type of carbon material insoluble in water, Se/C is bio-compatible and can adhere onto the leaves of the plants to allow a slow and sustained release of its efficacy, affording an efficient method for the cabbage black rot disease prevention and cure. This work as the first report on the bioactivity studies of Se/C significantly expands the application scopes of the selenium-containing materials and may draw continuous attentions from a broad field.
Simple manganese carbonyl catalyzed hydrogenation of quinolines and imines
Wang Zelong , Chen Lei , Mao Guoliang , Wang Congyang
2020, 31(7): 1890-1894  doi: 10.1016/j.cclet.2020.02.025
[Abstract](16) [FullText HTML] [PDF 5578KB](0)
Abstract:
Manganese-catalyzed hydrogenation of unsaturated molecules has made tremendous progresses recently benefiting from non-innocent pincer or bidentate ligands for manganese. Herein, we describe the hydrogenation of quinolines and imines catalyzed by simple manganese carbonyls, Mn2(CO)10 or MnBr(CO)5, thus eliminating the prerequisite pincer-type or bidentate ligands.
Visible-light-initiated malic acid-promoted cascade coupling/ cyclization of aromatic amines and KSCN to 2-aminobenzothiazoles without photocatalyst
He Wei-Bao , Gao Lan-Qing , Chen Xin-Jie , Wu Zhi-Lin , Huang Ying , Cao Zhong , Xu Xin-Hua , He Wei-Min
2020, 31(7): 1895-1898  doi: 10.1016/j.cclet.2020.02.011
[Abstract](26) [FullText HTML] [PDF 2939KB](0)
Abstract:
By using ambient air as the oxidant and malic acid as the promoter, a practical method for the preparation of 2-aminobenzothiazoles through visible-light-initiated cascade reaction of aromatic amines and KSCN in eco-friendly bis(methoxypropy)ether under metal-, hazardous additive-, photocatalyst-free conditions was established.
Tailorable carbazolyl cyanobenzene-based photocatalysts for visible light-induced reduction of aryl halides
Ou Wei , Zou Ru , Han Mengting , Yu Lei , Su Chenliang , Wei Ou , Ru Zou , Han Mengting , Yu Lei , Su Chenliang
2020, 31(7): 1899-1902  doi: 10.1016/j.cclet.2019.12.017
[Abstract](41) [FullText HTML] [PDF 3643KB](0)
Abstract:
Herein, a series of carbazolyl cyanobenzene (CCB)-based organic photocatalysts with a broad range of photoredox capabilities were designed and synthesized, allowing precise control of the photocatalytic reactivity for the controllable reduction of aryl halides via a metal-free process. The screened-out CCB (5CzBN), a metal-free, low-cost, scalable and sustainable photocatalyst with both strong oxidative and reductive ability, exhibits superior performance for both dehalogenation and C-C bond-forming arylation reactions.
Assembly of the 6/3/5/6 tetracyclic core of rearranged-type C19-diterpenoid alkaloids
Meng Zhaoxiang , Mi Fen , Lu Fei , Tan Wei , Liu Xiao-Yu , Qin Yong
2020, 31(7): 1903-1905  doi: 10.1016/j.cclet.2020.01.043
[Abstract](13) [FullText HTML] [PDF 2117KB](0)
Abstract:
A synthetic study toward the structurally complex rearranged-type C19-diterpenoid alkaloids leading to construction of the strained 6/3/5/6 tetracyclic core is presented. The synthesis features an intramolecular Diels-Alder cycloaddition reaction to assemble the highly substituted central cyclopropane motif, which may serve as a key strategy for the total synthesis of relevant natural product molecules.
Synthesis of ACE tricyclic systems of daphnicyclidin A and dehy-droxymacropodumine A
Wang Qi , Zhang Chao , Yang Jun
2020, 31(7): 1906-1910  doi: 10.1016/j.cclet.2019.12.018
[Abstract](14) [FullText HTML] [PDF 3463KB](0)
Abstract:
The synthesis of the ACE tricyclic system ofdaphnicyclidin A and dehydroxymacropodumine A are developed. The key reactions include an efficient aldol reaction to introduce chiral fragment 33 for further construction of piperidine ring B and seven-membered ring C, a nucleophilic addition of lithium pentene to aldehyde for installation of ring E, and a photocatalytic decarboxylation conjugate addition to construct ring C.
Hetero diacylation of 1, 1-diborylalkanes: Practical synthesis of 1, 3-diketones
Zou Liang-Hua , Fan Min , Wang Lu , Liu Chao
2020, 31(7): 1911-1913  doi: 10.1016/j.cclet.2019.12.016
[Abstract](20) [FullText HTML] [PDF 1378KB](0)
Abstract:
An efficient protocol for the synthesis of asymmetric 1, 3-diketones was reported through diacylation of 1, 1-diborylalkanes using two different acyl sources. In this transformation, an enolate boron species was initially formed by introducing an acyl group, then it was trapped by another acyl group to form 1, 3-diketone. This method not only provided the gateway to obtain a series of 1, 3-diketones, but also afforded an operationally simple and efficient access to pyrazoles and isoxazoles.
Dynamic and reversible electrowetting with low voltage on the dimethicone infused carbon nanotube array in air
Wang Miao , Zhou Lei , Hou Yaqi , He Wen , Liu Wei , Wu Feng , Hou Xu
2020, 31(7): 1914-1918  doi: 10.1016/j.cclet.2020.04.059
[Abstract](13) [FullText HTML] [PDF 1749KB](0)
Abstract:
Unremitting efforts have been intensively making for pursuing the goal of the reversible transition of electrowetting owing to its vital importance to many practical applications, but which remains a major challenge for carbon nanotubes due to the irreversible electrochemical damage. Herein, we proposed a subtly method to prevent the CNT array from electrochemical damage by using liquid medium instead of air medium to form a liquid/liquid/solid triphase system. The dimethicone dynamically refills in CNT arrays after removing of voltage that makes the surface back to hydrophobic, which is an elegant way to not only decrease energy dissipation in electrowetting process but also obtain extra energy in reversible dewetting process. Repeated cycles of in situ experiments showed that more than four reversible electrowetting cycles could be achieved in air. It worth mention that the in situ reversible electrowetting voltage of the dimethicone infused CNT array has been lowered to 2 V from 7 V which is the electrowetting voltage for the pure CNT array. The surface of the dimethicone infused CNT array can maintain hydrophobicity with a contact angle of 145.6° after four cycles, compared with 148.1° of the initial state. Moreover, a novel perspective of theoretical simulations through the binding energy has been provided which proved that the charged CNTs preferred binding with water molecules thereby replacing the dimethicone molecules adsorbed on the CNTs, whereas reconnected with dimethicone after removing the charges. Our study provides distinct insight into dynamic reversible electrowetting on the nanostructured surface in air and supplies a way for precise control of wettability in surface chemistry, smart phase-change heat transfer enhancement, liquid lenses, microfluidics, and other chemical engineering applications.
Free radical oxidation reaction for selectively solvatochromic sensors with dynamic sensing ability
Shen Fengjuan , Wang Tao , Yu Xudong , Li Yajuan
2020, 31(7): 1919-1922  doi: 10.1016/j.cclet.2019.12.025
[Abstract](14) [FullText HTML] [PDF 3711KB](0)
Abstract:
A novel BODIPY (boradiazaindacene) dye denoted as BODIPY-DT containing terpyridine unit has been designed and characterized. The dye is found to be selective and visual solvatochromic sensor toward DMF among test organic solvents. The sensing process displays time-controllable, dynamic signal outputs in the emission colors including red, purple, yellow and even white emission colors. It is presented that selective free radical oxidation reaction happens during the recognition process.
TFA promoted multi-component reaction of aryldiazonium with sodium metabisulphite and thiols: Construction of thiosulfonate under transition-metal free conditions
Huang Cheng-Mi , Li Jian , Wang Shun-Yi , Ji Shun-Jun
2020, 31(7): 1923-1926  doi: 10.1016/j.cclet.2019.12.032
[Abstract](13) [FullText HTML] [PDF 1616KB](0)
Abstract:
A TFA promoted multi-component reaction of aryldiazonium with sodium metabisulphite and thiols to construct thiosulfonates under transition-metal free conditions is reported. The thiosulfonates were isolated in good yields with broad tolerance of functional group. Readily available inorganic Na2S2O5 was applied as the sulfur dioxide surrogate. This strategy features easily available substrates, mild reaction conditions and free transition-metal catalyst.
Solar cells sensitized by porphyrin dyes containing a substituted carbazole donor with synergistically extended absorption and suppressed the dye aggregation
Tang Yunyu , Liu Xiujun , Wang Yueqiang , Liu Qingyun , Li Xin , Li Chengjie , Shen Xiaosheng , Xie Yongshu
2020, 31(7): 1927-1930  doi: 10.1016/j.cclet.2019.12.038
[Abstract](18) [FullText HTML] [PDF 1843KB](0)
Abstract:
To achieve high power conversion efficiency (PCE), three porphyrin sensitizers have been synthesized and explored to simultaneously enhance the photocurrent (Jsc) and photovoltage (Voc). On basis of the XW4, a benzothiadiazole (BTD) unit has been introduced to afford XW57 with the aim to extend the absorption wavelength and enhance the light harvesting ability. As a result, a Jsc of 13.72 mA/cm2 has been obtained for XW57, higher than that of XW4. On this basis, XW58 has been prepared by modifying the carbazole-based donor with two bulky dihexyloxyphenyl groups, and the superior anti-aggregation character raises the Voc from 781 mV (XW4) to 844 mV. When both the BTD unit and the bulky groups are introduced to the acceptor and donor units, respectively, the resulting sensitizer XW59 exhibits a highest PCE value of 7.34% with synergistically enhanced Jsc of 13.19 mA/cm2 and Voc of 793 mV. These results provide further insight into developing high performance dye-sensitized solar cells
Synthesis and self-assembly of poly(ethylene glycol)-block-poly(N-3-(methylthio)propyl glycine) and their oxidation-sensitive polymersomes
Deng Yangwei , Chen Hui , Tao Xinfeng , Trépout Sylvain , Ling Jun , Li Min-Hui
2020, 31(7): 1931-1935  doi: 10.1016/j.cclet.2019.12.026
[Abstract](14) [FullText HTML] [PDF 2979KB](0)
Abstract:
Amphiphilic block copolymers poly(ethylene glycol)-block-poly(N-3-(methylthio)propyl glycine) (PEG-b-PMeSPG) were synthesized via ring-opening polymerization of N-3-(methylthio)propyl glycine N-thiocarboxyanhydride (MeSPG-NTA) initiated by amino-terminated PEG. The self-assemblies of three PEG-b-PMeSPG copolymers with different PMeSPG block lengths were first prepared by nanoprecipitation method using THF and DMF, respectively, as the organic solvent, and their morphologies were studied by Cryo-EM and DLS. To prepare polymersomes loaded with glucose oxidase (GOx), double emulsion method followed by extrusion treatment was employed. The oxidation-responsive disruption of polymersomes was achieved upon the introduction of glucose because of the oxidants generated in-situ by GOx/glucose.
Scalable exfoliation for few-layered hexagonal boron nitride nanosheets (BNNSs) by microwave-assisted expansion and liquid nitrogen intercalation
Ma Zhansheng , Liu Zan , Cheng Zhilin
2020, 31(7): 1936-1940  doi: 10.1016/j.cclet.2020.01.019
[Abstract](11) [FullText HTML] [PDF 5534KB](0)
Abstract:
The low cost and facile scalable exfoliation route for two-dimensional hexagonal boron nitride (h-BN) was still indispensable for potential applications. In this work, we presented a convenient and scalable exfoliation for few-layer BNNSs. Taking advantage of the advantages of swift heating of microwave and ultra low temperature vaporization of liquid nitrogen, bulk h-BN was high-efficiently exfoliated into fewlayer BNNSs. The as-exfoliated BNNSs had a 2-6 nm thickness and approximately 7.91% yield, exhibiting scalable, facile and environment-friendly features. Furthermore, the as-exfoliated BNNSs were applied as additive in oil for reducing friction of oil. The COF of the BNNSs-based grease reduced by 20.10% compared to grease, and the antiwear performance decreased by 55.8% and 45.1% relative to grease and h-BN-based grease.
Cu/Cu2O nanostructures derived from copper oxalate as high performance electrocatalyst for glucose oxidation
Yuan Guoqiang , Yu Shangkui , Jie Ji , Wang Chen , Li Qing , Pang Huan
2020, 31(7): 1941-1945  doi: 10.1016/j.cclet.2019.12.034
[Abstract](15) [FullText HTML] [PDF 3766KB](0)
Abstract:
Porous nanomaterials are classified as a kind of materials with great potential for development in the field of electrocatalysis, but there is still room for further improvement as catalysts. We develop a threedimensional (3D) porous structure of Cu/Cu2O as an electrocatalyst for the glucose oxidation reaction (GOR) using the method of calcining the precursor CuC2O4·2H2O in N2. The obtained porous Cu/Cu2O nanostructure can provide more opportunities for effective reactions between particles, which can explain their efficient electrocatalytic performance. Additionally, the as-synthesized Cu/Cu2O nanostructure exhibits outstanding electrocatalytic performance for the glucose, including good stability, excellent sensitivity and remarkable selectivity.
Getting rid of NaBH4: Gold seeds reduced by air-stable agents for synthesizing quasi one-dimensional gold nanoparticles
Sun Jinxia , Luo Rong , Xia Yunsheng
2020, 31(7): 1946-1950  doi: 10.1016/j.cclet.2019.12.037
[Abstract](14) [FullText HTML] [PDF 5284KB](0)
Abstract:
Herein, we have presented a novel and easy to operate seed-mediated system for fabricating gold bipyramids (AuBPs) with 85% yields without any separation/purification processes. The used gold seeds are reduced by tannin and citrate, two kinds of air stable ligands, and conventionally employed unstable NaBH4 are thoroughly cast off. In addition, the as-proposed gold seeds can also be employed for AuNRs fabrication with rather larger diameters (22.2-60.3 nm), which is difficult to be achieved by conventional seed mediated fabrication system.
Molecular simulations of host-guest interactions between zeolite framework STW and its organic structure-directing agents
Shi Chao , Li Lin , Yang Lixia , Li Yi
2020, 31(7): 1951-1955  doi: 10.1016/j.cclet.2020.01.016
[Abstract](13) [FullText HTML] [PDF 2816KB](0)
Abstract:
Zeolites have been widely applied in many chemical processes owing to their featured microporous framework structures. Organic structure-directing agents (OSDAs) play an important role during of the formation of zeolite frameworks via non-bonding host-guest interactions. Understanding these interactions is crucial to the design of OSDAs and the synthesis of target zeolites. Here, we report a molecular simulation study in the host-guest interactions between zeolite framework STW and 21 alkylated imidazolium and pyrazolium cations that have been used as the OSDAs for the synthesis of STW-type zeolites. We find that OSDAs that have successfully directed the formation of STW exhibit stronger host-guest interactions than unsuccessful ones. Furthermore, we find all successful OSDAs possess relatively more negative atomic charges on nitrogen atoms and smaller dipole moments. According to this finding, we have designed seven new alkylated imidazolium and pyrazolium cations that may be suitable for zeolite STW, and verified their structure-directing capability by molecular simulation calculations.
Extraction of Cr(VI) from chromite ore processing residue via hydrothermal-assisted phase transformation
Mo Xiaofeng , Zhou Jin , Lin Le , Zhong Zuqi , Yang Shaohua , Liu Xueming , Shi Zhenqing , Zhao Dongye , Lin Zhang
2020, 31(7): 1956-1960  doi: 10.1016/j.cclet.2019.11.040
[Abstract](14) [FullText HTML] [PDF 4112KB](0)
Abstract:
The effective extracting Cr(VI) from chromite ore processing residue (COPR) is the key to achieve COPR detoxification and recovery. We developed an effective method to extract Cr(VI) from COPR via controlling the phase transformation of Cr(VI)-containing minerals. Characteristic analysis showed that Cr(VI) was mainly incorporated in the hydrocalumite (NaCa4Al2O6(SO4/CrO4)1.5·15H2O) in COPR, which was a layered-double hydroxide (LDH) with multilayer structure. In the hydrothermal treatment experiments, the Na2CO3 solution showed significant extraction effect of Cr(VI) and detoxification effect of COPR. After treatment, 95% of Cr(VI) was removed and the Cr(VI) concentration in the leachate was decreased to 1.6 mg/L by the toxicity characteristic leaching procedure (TCLP), within the regulatory limit disposal standard (HJ/T 301-2007, 3 mg/L). Further study revealed that, during the treatment, hydrocalumite transformed into calcite (CaCO3) under the effect of mineralizer, therefore, the layered structure collapsed and the incorporated Cr(VI) was released to the supernatant. Meanwhile, the Cr(VI) desorbed from calcite with the calcite particles grew into large size with smooth surface. Stir-flow experiment revealed that the amount of chromium released from CORP to the environment was significantly reduced after treatment, and it is safer for landfill disposal. This work will provide an instructive guidance for the detoxification and recovery of COPR.
Degradation of 4-nitrophenol by electrocatalysis and advanced oxidation processes using Co3O4@C anode coupled with simultaneous CO2 reduction via SnO2/CC cathode
Zhu Meng , Zhang Longshuai , Liu Shanshan , Wang Dengke , Qin Yuancheng , Chen Ying , Dai Weili , Wang Yuehua , Xing Qiuju , Zou Jianping
2020, 31(7): 1961-1965  doi: 10.1016/j.cclet.2020.01.017
[Abstract](17) [FullText HTML] [PDF 5982KB](0)
Abstract:
Herein, we prepared novel three-dimensional (3D) gear-shaped Co3O4@C (Co3O4 modified by amorphous carbon) and sheet-like SnO2/CC (SnO2 grow on the carbon cloth) as anode and cathode to achieve efficient removal of 4-nitrophenol (4-NP) in the presence of peroxymonosulfate (PMS) and simultaneous electrocatalytic reduction of CO2, respectively. In this process, 4-NP was mineralized into CO2 by the Co3O4@C, and the generated CO2 was reduced into HCOOH by the sheet-like SnO2/CC cathode. Compared with the pure Co0.5 (Co3O4 was prepared using 0.5 g urea) with PMS (30 mg, 0.5 g/L), the degradation efficiency of 4-NP (60 mL, 10 mg/L) increased from 74.5%-85.1% in 60 min using the Co0.5 modified by amorphous carbon (Co0.5@C). Furthermore, when the voltage of 1.0 V was added in the anodic system of Co0.5@C with PMS (30 mg, 0.5 g/L), the degradation efficiency of 4-NP increased from 85.1%-99.1% when Pt was used as cathode. In the experiments of 4-NP degradation coupled with simultaneous electrocatalytic CO2 reduction, the degradation efficiency of 4-NP was 99.0% in the anodic system of Co0.5@C with addition of PMS (30 mg, 0.5 g/L), while the Faraday efficiency (FE) of HCOOH was 24.1% at voltage of -1.3 V using the SnO2/CC as cathode. The results showed that the anode of Co3O4 modified by amorphous carbon can markedly improve the degradation efficiency of 4-NP, while the cathode of SnO2/CC can greatly improve the FE and selectivity of CO2 reduction to HCOOH and the stability of cathode. Finally, the promotion mechanism was proposed to explain the degradation of organic pollutants and reduction of CO2 into HCOOH in the process of electrocatalysis coupled with advanced oxidation processes (AOPs) and simultaneous CO2 reduction.
Single atom catalytic oxidation mechanism of formaldehyde on Al doped graphene at room temperature
Liu Guanlan , Zhou Junhui , Zhao Weina , Ao Zhimin , An Taicheng
2020, 31(7): 1966-1969  doi: 10.1016/j.cclet.2019.12.023
[Abstract](15) [FullText HTML] [PDF 3011KB](0)
Abstract:
Formaldehyde (HCHO) is one kind of common indoor toxic pollutant, the catalytic oxidation degradation of formaldehyde at room temperature is desired. In this work, a new single atomic catalyst (SAC), Al doped graphene, for the catalytic oxidation of HCHO molecules was proposed through density function theory (DFT) calculations. It is found that Al atoms can be adsorbed on graphene stably without aggression. Then HCHO can be effectively oxidized into CO2 and H2O in the presence of O2 molecules on Al doped graphene with a low energy barrier of 0.82 eV and releasing energy of 2.29 eV with the pathway of HCHO → HCOOH → CO → CO2. The oxidation reaction can happen promptly with reaction time τ = 56.9 s at the speed control step at room temperature. Therefore, this work proposed a high-performance catalyst Al-doped graphene without any noble metal for HCHO oxidation at ambient temperature, and corresponding oxidation pathway and mechanism are also deeply understood.
Dissolved organic matter-mediated reduction of ionic Au(Ⅲ) to elemental Au nanoparticles and their growth to visible granules
Chen Ying , Guo Yingying , Liu Guangliang , Song Maoyong , Cai Yong , Yin Yongguang
2020, 31(7): 1970-1973  doi: 10.1016/j.cclet.2019.11.030
[Abstract](15) [FullText HTML] [PDF 3806KB](0)
Abstract:
The biogeochemical transformation of gold (Au), i.e. its dissolution and re-precipitation, is critical in supergene transport of Au and formation of Au granules. Besides biogenic reduction, the formation Au granules can also be driven by chemical processes. Previous studies have showed the formation of Au nanoparticles (AuNPs) from ionic Au(Ⅲ) can be mediated by dissolved organic matter under sunlight. In this letter, we further demonstrated that these AuNPs can further slowly (in years) grow into visible Au granules. Different sized nano-flower and fractal dendrite-like branched gold structures (from tens of nanometres to over 100 μm) were observed in the Au granule sample. This growth of AuNPs into visible Au granules may play a critical role in the supergene mineralization and enrichment of secondary Au and drive the biogeochemical cycle of Au.
Chromate separation by selective crystallization
Chen Xijian , Dai Xing , Xie Rongzhen , Li Jie , Khayambashi Afshin , Xu Lei , Yang Chuang , Shen Nannan , Wang Yaxing , He Linwei , Zhang Yugang , Xiao Chengliang , Chai Zhifang , Wang Shuao
2020, 31(7): 1974-1977  doi: 10.1016/j.cclet.2019.11.034
[Abstract](14) [FullText HTML] [PDF 3271KB](0)
Abstract:
A new paradigm to remove toxic chromate anions from aqueous solution by crystallization of chromatewater clusters with imine-linked guanidinium cationic ligands is introduced. The guanidium-based cationic ligand was easily prepared through the imine condensation of an aldehyde and aminoguanidine hydrochloride. The cationic imine-linked guanidinium ligand (BBIG-Cl) showed a high removal capacity (292.5 mg/g) in the solutions. Rapid decontamination of chromate anions from the wastewater by this cationic ligand was resulted from an instantaneous crystallization. The produced guanidium chromate salts have an extremely low solubility (Ksp, BBIG = 8.19×10-9). Such superior removal performance of these materials was attributed to the charge-assisted hydrogen bonding between the cationic ligand and chromate-water hydrate anions, which was revealed by the single-crystal X-ray diffraction analysis and density functional theory (DFT) calculations. In addition, the successful recovery of the guanidium-based ligand makes it more attractive for real-world applications.
Mechanochemically sulfured FeS1.92 as stable and efficient heterogeneous Fenton catalyst
Guo Chao , Yue Dongting , Wang Songling , Qian Xufang , Zhao Yixin
2020, 31(7): 1978-1981  doi: 10.1016/j.cclet.2019.11.049
[Abstract](17) [FullText HTML] [PDF 4372KB](0)
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Fenton reaction is one of most promising approaches for efficient removal of various robust organic pollutants in wastewater, however it faces several intrinsic challenges such as acidic condition, sludge waste and sensitive to sulfide-containing compound. Here we reported a novel FeS1.92 as an efficient and sulfide resistant heterogeneous Fenton catalyst under mild condition. This novel FeS1.92 was facilely prepared through a mechanochemical synthesis of mackinawite (FeS) with sulfur powder (S) by ball milling. The sulfured mackinawite (FeS1.92) exhibits high performance in activating H2O2 to generate hydroxyle radicals for organic waste remediation. Furthermore, this FeS1.92 based heterogeneous Fenton catalyst is highly sulfide resistant and shows improved performance for degrading sulfide-containing organic pollutants. This study provides an effective mechanochemical approach to fabricate heterogeneous Fenton catalysts for sulfide-containing wastewater treatment.
Aptamer structure switch fluorescence anisotropy assay for aflatoxin B1 using tetramethylrhodamine-guanine interaction to enhance signal change
Li Yapiao , Zhao Qiang
2020, 31(7): 1982-1985  doi: 10.1016/j.cclet.2020.01.022
[Abstract](13) [FullText HTML] [PDF 1183KB](0)
Abstract:
Fluorescence anisotropy (FA) assay in homogenous solution is simple, sensitive and reproducible. Here, we reported an aptamer structure switch FA assay for detection of aflatoxin B1 (AFB1), one of the most toxic mycotoxins, by using tetramethylrhodamine (TMR)-labeled aptamer probe and its complementary DNA (cDNA) with tandem G bases extension, to meet the demand in sensitive and selective detection of AFB1. The hybridization of aptamer and cDNA drew TMR close to the repeated guanine (G) bases, and a high FA value was induced due to TMR-G interaction and restricted local rotation of TMR. In the presence of AFB1, aptamer bound to AFB1 instead of the cDNA due to competition. Thus, the TMR-G interaction was eliminated, and FA value of TMR decreased. This assay enabled the detection of AFB1 with detection limit of 125 pmol/L and dynamic range from 125 pmol/L to 31.2 nmol/L
N-doped honeycomb-like porous carbon towards high-performance supercapacitor
Wang Feng , Chen Lian , Li Huiling , Duan Gaigai , He Shuijian , Zhang Lin , Zhang Guoying , Zhou Zhengping , Jiang Shaohua
2020, 31(7): 1986-1990  doi: 10.1016/j.cclet.2020.02.020
[Abstract](15) [FullText HTML] [PDF 5123KB](0)
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Biomass-derived porous carbon with developed pore structure is critical to achieving high performance electrode materials. In this work, we report a grape-based honeycomb-like porous carbon (GHPC) prepared by KOH activation and carbonization, followed by N-doping (NGHPC). The obtained NGHPC exhibits a unique honeycomb-like structure with hierarchically interconnected micro/mesopores, and high specific surface area of 1268 m2/g. As a supercapacitor electrode, the NGPHC electrode exhibits a remarkable specific capacitance of 275 F/g at 0.5 A/g in a three-electrode cell. Moreover, the NGHPC//NGHPC symmetric supercapacitor displays a high energy density of 12.6 Wh/kg, and excellent cycling stability of approximately 95.2% capacitance retention after 5000 cycles at 5 A/g. The excellent electrochemical performance of NGHPC is ascribed to its high specific surface area, honeycomb-like structure and high-content of pyrodinic-N (36.29%). It is believed that grape-based carbon materials show great potential as advanced electrode materials for supercapacitors.
High-efficiency organic solar cells with low voltage-loss of 0.46 V
Yu Zhi-Peng , Li Xue , He Chengliang , Wang Di , Qin Ran , Zhou Guanqing , Liu Zhi-Xi , Andersen Thomas Rieks , Zhu Haiming , Chen Hongzheng , Li Chang-Zhi
2020, 31(7): 1991-1996  doi: 10.1016/j.cclet.2019.12.003
[Abstract](21) [FullText HTML] [PDF 5607KB](0)
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The recent evolution of active components yielded brilliant progresses for organic solar cells (OSCs), yet the mechanism is needed to be clearly understood. In this work, two electron acceptors, a linear SN6-2Br and a V-shaped BTP-2Br, are developed with nitrogen atoms introduced to replace the traditional sp3-hybridized carbon in the fused ring. BTP-2Br possesses an electron-deficient central core, which exhibits slightly blue-shifted absorption as well as deepened HOMO-level compared with SN6-2Br. The corresponding photovoltaic performance from V-shaped BTP-2Br based devices exhibit superior performance especially in short-circuit current (Jsc), despite an enhanced absorption and charge carrier mobilities for SN6-2Br. The primary reason for the higher Jsc from BTP-2Br is faster exciton diffusion and dissociation in blends, than those of SN6-2Br. As a result, PBDB-TF:BTP-2Br based devices achieve a power conversion efficiency (PCE) of 13.84% with an voltage-loss of only 0.46 V, which is one of the lowest values ever reported. Moreover, we fabricated semitransparent OSCs that exhibit an excellent PCE of 9.62% with average visible transparency of 20.1%.
Remarkable improvement of cyclic stability in Li-O2 batteries using ruthenocene as a redox mediator
Zhu Cuicui , Wang Yiping , Shuai Ling , Tang Yizhao , Qiu Ming , Xie Jian , Liu Jia , Wen Wen , Chen Hengquan , Nan Suifei , Dou Mei , He Qinggang
2020, 31(7): 1997-2002  doi: 10.1016/j.cclet.2019.11.046
[Abstract](16) [FullText HTML] [PDF 4353KB](0)
Abstract:
Nonaqueous Li-O2 batteries attract attention for their theoretical specific energy density. However, due to the difficulty of decomposition of Li2O2, Li-O2 batteries have high charge overpotential and poor cycling life. So all kinds of catalysts have been studied on the cathode. Compared to heterogeneous solid catalysts, soluble catalysts achieve faster and more effective transport of electrons by reversible redox pairs. Here, we first report ruthenocene (Ruc) as a mobile redox mediator in a Li-O2 battery. 0.01 mol/L Ruc in the electrolyte effectively reduces the charging voltage by 610 mV. Additionally, Ruc greatly increases the cycling life by four-fold (up to 83 cycles) with a simple ketjen black (KB) cathode. The results of SEM, XPS and XRD confirm that less discharge product residue accumulated after recharge. To verify the reaction mechanisms of the mediator, free energy profiles of the possible reaction pathways based on DFT are provided.
Yolk-shell structured Fe@void@mesoporous silica with high magnetization for activating peroxymonosulfate
Xu Bingqian , Jiang Wan , Wang Lianjun , Thokchom Binota , Qiu Pengpeng , Luo Wei
2020, 31(7): 2003-2006  doi: 10.1016/j.cclet.2019.12.035
[Abstract](19) [FullText HTML] [PDF 3178KB](0)
Abstract:
Sulfate radical anion (SO4·-) based Fenton-like reaction have recently received a large quantity of attention owing to their strong oxidative capacity and high selectivity toward organic pollutants. However, the development of a high-efficient catalyst for activation of peroxymonosulfate (PMS) with a fast separation is still challengeable. Herein, magnetic mesoporous silica composites with a yolk-shell structure (Fe@void@mSiO2) have been prepared via a successive coating strategy, followed by a hightemperature in-situ treatment and demonstrated as a high-efficient and fast magnetic separable catalyst for the activation of PMS. The resultant material possesses a well-defined yolk-shell structure with high specific surface area (~495.0 m2/g), uniform pore size (~6.9 nm) and super large magnetic susceptibility (~105 emu/g). Owing to the unique properties, the material possesses an excellent degradation activity for tetracyclines (TC), which is much higher than the commercialized Zero Valent Iron (ZVI) nanoparticles. Additionally, the catalyst is able to work over a broad pH range and be quickly recycled by using an external magnetic field. This research provides a promising strategy for the synthesis and design of multifunctional catalyst for the Fenton-like process.
ZIF-67 derived hollow Ni-Co-Se nano-polyhedrons for flexible hybrid supercapacitors with remarkable electrochemical performances
Qu Guangmeng , Zhang Xixi , Xiang Guotao , Wei Yunrui , Yin Jiangmei , Wang Zonghua , Zhang Xiaoli , Xu Xijin
2020, 31(7): 2007-2012  doi: 10.1016/j.cclet.2020.01.040
[Abstract](14) [FullText HTML] [PDF 7701KB](0)
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Nano-polyhedral NiSe2/CoSe2 (Ni-Co-Se) with hollow architectures are synthesized by selenizing the precursors of Ni-Co bimetallic hydroxides that are directly derived from ZIF-67. The as-fabricated Ni-Co-Se electrodes exhibit high specific capacitance of 1668 F/g at 1 A/g accompanying with outstanding rate capability (about 82.8% retention of the initial capacity at 20 A/g). The corresponding Ni-Co-Se//AC all-solid-state hybrid supercapacitors are assembled by directly using the Ni-Co-Se on carbon fabric as the positive electrode, which deliver high energy density and power density (38.5 Wh/kg at 802.1 W/kg, 32.0 Wh/kg at 8008.8 W/kg), excellent cyclic stability (82.3% retention after 5000 cycle) and robust mechanical flexibility (no obvious attenuation at bending to different angles). This work will provide a new and smart route for constructing transition metal selenides for supercapacitor devices.
Unprecedented differences in the diamond nucleation density between carbon- and silicon-faces of 4H-silicon carbides
Wang Bo , Sukkaew Pitsiri , Song Guichen , Rosenkranz Andreas , Lu Yunxiang , Nishimura Kazhihito , Wang Jia , Lyu Jilei , Cao Yang , Yi Jian , Ojamäe Lars , Li He , Jiang Nan
2020, 31(7): 2013-2018  doi: 10.1016/j.cclet.2019.11.026
[Abstract](17) [FullText HTML] [PDF 5251KB](0)
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4H-silicon carbides deposited by diamond films have wide applications in many fields such as semiconductor heterojunction, heat sink and mechanical sealing. Nucleation plays a critical role in the deposition of the diamond film on 4H-silicon carbides. Nevertheless, as a typical polar material, the fundamental mechanism of diamond nucleation on different faces of 4H-silicon carbides has not been fully understood yet. In this contribution, nucleation of diamond was performed on the carbon- and silicon-faces of 4H-silicon carbides in a direct current chemical vapor deposition device. The nucleation density on the carbon-face is higher by 2-3 orders of magnitude compared to the silicon-face. Transmission electron microscopy verifies that there are high density diamond nuclei on the interface between the carbon-face and the diamond film, which is different from columnar diamond growth structure on the silicon-face. Transition state theory calculation reveals that the unprecedented distinction of the nucleation density between the carbon-face and the silicon-face is attributed to different desorption rates of the absorbed hydrocarbon radicals. In addition, kinetic model simulations demonstrate that it is more difficult to form CH2(s)-CH2(s) dimers on silicon-faces than carbon-faces, resulting in much lower nucleation densities on silicon-faces.
Ultrasmall Ru nanoparticles supported on chitin nanofibers for hydrogen production from NaBH4 hydrolysis
Zhang Jiapeng , Lin Fanzhen , Yang Lijing , He Zhaoyi , Huang Xiaoshan , Zhang Dingwei , Dong Hua
2020, 31(7): 2019-2022  doi: 10.1016/j.cclet.2019.11.042
[Abstract](21) [FullText HTML] [PDF 3118KB](0)
Abstract:
In this work, a series of chitin-supported Ru catalysts, composed of ultrasmall Ru nanoparticles supported on the chitin nanofibers, with different Ru content from 0.07 wt% to 0.93 wt%, are fabricated. Results from catalyzed NaBH4 hydrolysis experiments indicate that the catalytic activity of the fabricated chitin-supported Ru catalysts increases gradually with the decreasing of Ru content. The rate of hydrogen generation from NaBH4 hydrolysis catalyzed by the catalyst with 0.07 wt% Ru content is as high as 55.29 L min-1 at 30 ℃, and this reaction exhibits activation energy of 39.16 kJ/mol. The augment of NaBH4 dosage in the experiments does not weaken the catalytic activity. In addition, the fabricated chitin-supported Ru catalysts show excellent durability in NaBH4 hydrolysis, with only 9.2% activity loss after used for 20 cycles. With excellent catalytic activity and durability, the as-obtained Ru catalysts provide a promising choice for promoting hydrogen production from NaBH4 hydrolysis.
Control of random self-assembly of pyrogallol[4] arene-based nanocapsule or framework
Su Kongzhao , Du Shunfu , Wang Wenjing , Yuan Daqiang
2020, 31(7): 2023-2026  doi: 10.1016/j.cclet.2019.11.047
[Abstract](19) [FullText HTML] [PDF 4183KB](1)
Abstract:
The controlled self-assembly of discrete metal-organic nanocapsules (MONCs), and metal-organic frameworks (MOFs) based on the MONCs are achieved. Specifically, the solvothermal reaction of nickel nitrate hexahydrate and C-methylpyrogallol[4]arene in mixed DMF/MeOH solution leads to the unexpected form of discrete nickel-seamed hexameric pyrogallol[4]arene MONCs, and MONC-based three-dimensional (3D) MOF. Notably, the latter MOF is constructed from the aforementioned nickelseamed MONC building blocks and formate linkers in-situ generated from the hydrolysis of DMF solvent. Interestingly, introducing pyridine and formic acid in the reaction conditions leads to the controlled assemblies of the discrete MONC and MONC-based 3D MOF structures. Moreover, the variabletemperature magnetic susceptibilities of both the abovementioned compounds have been investigated, indicating typical antiferromagnetic interactions between the metal centers.
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