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Asymmetric Hybrid Capacitor Based on NiCo2O4 Nanosheets Electrode
Yongli Tong, Meizhen Dai, Lei Xing, Hengqi Liu, Wanting Sun, Xiang Wu
2020, 36(7): 1903046-0  doi: 10.3866/PKU.WHXB201903046
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摘要:
The looming global energy crisis and ever-increasing energy demands have catalyzed the development of renewable energy storage systems. In this regard, supercapacitors (SCs) have attracted widespread attention because of their advantageous attributes such as high power density, excellent cycle stability, and environmental friendliness. However, SCs exhibit low energy density and it is important to optimize electrode materials to improve the overall performance of these devices. Among the various electrode materials available, spinel nickel cobaltate (NiCo2O4) is particularly interesting because of its excellent theoretical capacitance. Based on the understanding that the performances of the electrode materials strongly depend on their morphologies and structures, in this study, we successfully synthesized NiCo2O4 nanosheets on Ni foam via a simple hydrothermal route followed by calcination. The structures and morphologies of the as-synthesized products were characterized by X-ray diffraction, scanning electron microscopy, and Brunauer-Emmett-Teller (BET) surface area analysis, and the results showed that they were uniformly distributed on the Ni foam support. The surface chemical states of the elements in the samples were identified by X-ray photoelectron spectroscopy. The as-synthesized NiCo2O4 products were then tested as cathode materials for supercapacitors in a traditional three-electrode system. The electrochemical performances of the NiCo2O4 electrode materials were studied and the area capacitance was found to be 1.26 C∙cm-2 at a current density of 1 mA∙cm-2. Furthermore, outstanding cycling stability with 97.6% retention of the initial discharge capacitance after 10000 cycles and excellent rate performance (67.5% capacitance retention with the current density from 1 to 14 mA∙cm-2) were achieved. It was found that the Ni foam supporting the NiCo2O4 nanosheets increased the conductivity of the electrode materials. However, it is worth noting that the contribution of nickel foam to the areal capacitance of the electrode materials was almost zero during the charge and discharge processes. To further investigate the practical application of the as-synthesized NiCo2O4 nanosheets-based electrode, a device was assembled with the as-prepared samples as the positive electrode and active carbon (AC) as the negative electrode. The assembled supercapacitor showed energy densities of 0.14 and 0.09 Wh∙cm-3 at 1.56 and 4.5 W∙cm-3, respectively. Furthermore, it was able to maintain 95% of its initial specific capacitance after 10000 cycles. The excellent electrochemical performance of the NiCo2O4 nanosheets could be ascribed to their unique spatial structure composed of interconnected ultrathin nanosheets, which facilitated electron transportation and ion penetration, suggesting their potential applications as electrode materials for high performance supercapacitors. The present synthetic route can be extended to other ternary transition metal oxides/sulfides for future energy storage devices and systems.
PtCo-NC Catalyst Derived from the Pyrolysis of Pt-Incorporated ZIF-67 for Alcohols Fuel Electrooxidation
Bo Fang, Ligang Feng
2020, 36(7): 1905023-0  doi: 10.3866/PKU.WHXB201905023
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摘要:
Alcohols fuel electro-oxidation is significant to the development of direct alcohols fuel cells, that are considered as a promising power source for portable electronic devices. Currently, the catalyst was restricted by the serious poisoning effect and high cost of noble metals. Developing low-cost Pt alloy with high performance and anti-CO poisoning ability was highly desired. In this work, PtCo-NC catalyst was synthesized by combining Pt nanoparticles with ZIF-67 after annealing in the tube furnace and the in situ generated N-doped carbon from ZIF-67 was functionalized to support the PtCo alloy nanoparticle. The structure and morphology were probed by X-ray diffraction, scanning electron microscope and transmission electron microscope, and the electrochemical performance was evaluated for alcohols of methanol and ethanol oxidation in the acid electrolyte. Compared with the reference sample of Pt/C, several times performance enhancement for alcohols fuel oxidation was found on PtCo-NC catalyst as well as the good catalytic stability. Specifically, the peak current density of PtCo-NC was 79.61 mA∙cm−2 for methanol oxidation, about 2.2 times higher than that of the Pt/C electrode (36.97 mA∙cm−2) and 2.5 times higher than that of the commercial Pt/C electrode (31.23 mA∙cm−2); it was 62.69 mA∙cm–2 for ethanol oxidation, about 1.65 times higher than that of Pt/C catalyst (37.99 mA∙cm−2) and commercial Pt/C electrode (37.77 mA∙cm−2). These catalytic performances were also much higher than some analogous catalysts developed for alcohols fuel oxidation. A much higher anti-CO poisoning ability was demonstrated by the CO stripping voltammetry experiment, in which the COad oxidation peak potential for PtCo-NC was 0.46 V, ca. 110 mV negative shift compared with Pt/C catalyst at 0.57 V. A strong electronic effect was indicated by the peak position shifting to the lower binding energy direction by 0.3 eV on PtCo-NC compared with Pt/C reference catalyst. According to the d-band center theory, the electron-enriched state of Pt will decrease the interaction strength of poisoning intermediates adsorbed on its surface; Moreover, according to the bifunctional catalytic mechanism, the presence of Co can form the adsorbed oxygen-containing species (OH) more easily than Pt at low potentials, and this oxygen-species were helpful in the oxidation of COad at neighboring Pt sites. The high catalytic performance for alcohols fuel oxidation could be due to the largely improved anti-CO poisoning ability and the synergistic effect between the in situ formed PtCo nanoparticles and the N-doped carbon support.
Control of Nitrogen Vacancy in g-C3N4 by Heat Treatment in an Ammonia Atmosphere for Enhanced Photocatalytic Hydrogen Generation
Juanjuan Huang, Jianmei Du, Haiwei Du, Gengsheng Xu, Yupeng Yuan
2020, 36(7): 1905056-0  doi: 10.3866/PKU.WHXB201905056
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摘要:
Graphite phase carbon nitride (g-C3N4) has shown excellent potential when applied to photocatalytic hydrogen (H2) generation upon exposure to visible light. However, the photocatalytic activity during hydrogen generation remains very low because of the high recombination rate of photogenerated electron-hole pairs and poor conductivity. Of the various strategies to improve H2 generation efficiency, N vacancies have proven to be effective at increasing the photocatalytic performance of g-C3N4. However, creating a N vacancy is primarily dependent on the post-heating of g-C3N4 in air at an elevated temperature, which generates a high concentration of N vacancies and consequent decreased crystallinity of g-C3N4. Thus, as-produced g-C3N4 offers low photocatalytic efficiency owing to the high recombination rate of photogenerated electron-hole pairs. Currently, controlling the concentration of N vacancy in g-C3N4 is an immense challenge. Herein, we report an effective means of achieving controllable N vacancies in g-C3N4 via urea in-situ generated NH3 at an elevated temperature. Specifically, g-C3N4 was first prepared with dicyandiamide as a precursor and subjected to rapid post-thermal treatment at 650 ℃ in a tubular furnace for 10 min, in which a desired amount of urea was mixed with g-C3N4 as the source material for NH3. X-ray diffraction analysis showed increased crystallinity and an unchanged crystal structure as compared to pristine g-C3N4. X-ray photoelectron spectroscopy and elemental analysis verified the reduced levels of N-vacancy concentration with urea added as the NH3 source when compared to the g-C3N4 post-heated in air without the addition of urea. In addition, UV-Vis spectra displayed an increased visible light absorption due to the generated N vacancies. Moreover, the specific surface area of g-C3N4 was progressively enlarged with an increase in the amount of urea added. The high crystallinity, low N-vacancy concentration, increased light absorption, and enlarged surface area translated into markedly increased photocatalytic H2 generation. The highest H2 generation rate from the optimized added amount of urea was 6.5 μmol·h-1, which was three times higher than that when using a g-C3N4 sample thermally treated without urea addition. The H2 generation enhancement was also the result of the increased separation efficiency of photogenerated electron-hole pairs as exemplified by the significantly decreased photoluminescence spectra and large transient photocurrent. The results of this study demonstrate the simultaneous production of highly crystalline g-C3N4 and controllable creation of N vacancy by in-situ generated NH3 through thermal decomposition of urea. This study reveals the immense potential of NH3 at controlling the N-vacancy concentration of g-C3N4 for increased photocatalytic H2 generation.
Inside-Out Migration of Noble Metals in Ag2S Nanoparticles
Danye Liu, Dong Chen, Hui Liu, Jun Yang
2020, 36(7): 1906069-0  doi: 10.3866/PKU.WHXB201906069
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Materials such as metals, semiconductors, and oxides are attractive at nanometer scales due to the physical and chemical property differences with their bulk counterparts as induced by the quantum confinement effect and large surface-to-volume ratios. In particular, heterogeneous nanostructures consisting of semiconductors and noble metals are extremely important because of the synergistic effects occurring at the interfaces between their noble metal and semiconductor domains; these often equip the heterogeneous nanostructures with improved properties compared to those of isolated individual components. Thus far, heterogeneous nanostructures have garnered a considerable research interest, and tremendous development in achieving high degree control over these nanostructures with respect to their domain size, morphology, and composition has been realized. Their immense application potential in optics, catalysis, imaging, and biomedicine render them a field full of original innovation possibilities. Herein, we demonstrate a phenomenon observed in core-shell nanostructures composed of noble metals and silver sulfide (Ag2S): the inside-out migration of noble metals in Ag2S nanoparticles. We prepare core-shell nanostructures with noble metals and Ag2S residing at the core and shell regions, respectively, through various synthetic strategies including seed-mediated growth and galvanic replacement reactions followed by sulfidation. We then characterize the core-shell nanostructures before and after aging them in toluene at room temperature (e.g. 25 ℃) for a period of time up to 72 h. In contrast to the reported diffusion of Au from the outside to the inside of InAs or PbTe nanoparticles, which results in an Au core encapsulated by an amorphous InAs or PbTe shell, the noble metals (Au, Ag, Pd, or Pt) in core-shell nanostructures with noble metals and Ag2S residing at the core and shell regions, respectively, are found to diffuse from the inside to the outside through the Ag2S shell. Thus, heterogeneous nanodimers consisting of the corresponding noble metal and Ag2S are formed. Observations using an electron transmission microscope confirm that the inside-out migration of noble metals in Ag2S is carried out in a holistic manner. Due to the apparent interface mismatch between face-centered cubic noble metals and monoclinic Ag2S crystal phases, defects such as vacancies must exist at these interfaces. This makes the migration of noble metals in Ag2S possible by either a vacancy/substitutional mechanism or by the self-purification mechanism that occurs intrinsically in nanoscale semiconductors. As the migration rate of noble metals in Ag2S increases with the decrease in the size of the noble metal core and the radius of noble metal atoms, the inside-out migration rates of Ag, Pd, and Pt in Ag2S are found to be much higher than that of Au because of their smaller particle sizes or atom radii. This scientific phenomenon can be effective in the development of synthetic routes for heterogeneous nanostructures that might not be obtained by conventional methods.
Construction of Pt-M (M = Co, Ni, Fe)/g-C3N4 Composites for Highly Efficient Photocatalytic H2 Generation
Liang Wang, Chenglu Zhu, Lisha Yin, Wei Huang
2020, 36(7): 1907001-0  doi: 10.3866/PKU.WHXB201907001
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Platinum (Pt) is recognized as an excellent cocatalyst which not only suppresses the charge carrier recombination of the photocatalyst but also reduces the overpotential for photocatalytic H2 generation. Albeit of its good performance, the high cost and low abundance restricted the utilization of Pt in large-scale photocatalytic H2 generation. Pt based transition metal alloys are demonstrated to reveal enhanced activities towards various catalytic reactions, suggesting the possibility to substitute Pt as the cocatalyst. In the present work, Pt was partially substituted with Co, Ni, and Fe and Pt-M (M = Co, Ni, and Fe)/g-C3N4 composites were constructed through co-reduction of H2PtCl6 and transition metal salts by the reductant of ethylene glycol. The crystal structure and valence states were measured by X-ray diffractometer (XRD) and X-ray photoelectron spectrometer (XPS), respectively. The higher degree of XRD peaks and larger binding energies for Pt 4f5/2 and Pt 4f7/2 after incorporating Co2+ ions indicated that Co was successfully introduced into the lattice of Pt and Pt-Co bimetallic alloys was attained through the solvothermal treatment. The morphology was subsequently observed by transmission electron microscope (TEM), which showed a good dispersion of Pt-Co nanoparticles on the surface of g-C3N4. Meanwhile, the shrinkage of lattice fringe after introducing cobalt salt further confirmed the presence of Pt-Co bimetallic alloys. The UV-Vis absorption spectra of g-C3N4 and Pt, Pt-Co deposited g-C3N4 were subsequently performed. It was found that the absorption edges were all consistent for all three samples as anticipated, implying that the band gap energy was maintained after hybridizing with Pt or Pt-Co alloys. Furthermore, the photocatalytic H2 generation was carried out over the as-prepared composites with triethanolamine (TEOA) as sacrificial reagent. Under visible-light illumination, the1% (w) Pt2.5M/g-C3N4 (M = Co, Fe, Ni) composites all exhibited higher or comparable activity towards photocatalytic H2 generation when compared to 1% (w) Pt loaded counterpart. In addition, the atomic ratios of Pt/Co and the loading amount of Pt-Co cocatalyst were modified to optimize the photocatalytic performance, among which, 1% (w) Pt2.5Co/g-C3N4 composite revealed the highest activity with a 1.6-time enhancement. Electrochemical impedance spectra (EIS) and photoluminescence (PL) spectra indicated that the enhancement might be attributed to improved charge transfer from g-C3N4 to Pt2.5Co cocatalyst and inhibited charge carrier recombination in the presence of Pt2.5Co cocatalyst. Therefore, the present study demonstrates the great potential to partially replace Pt with low-cost and abundant transition metals and to fabricate Pt based bimetallic alloys as promising cocatalysts for highly efficient photocatalytic H2 generation.
Coating and Transforming the Y(OH)CO3 Shell on Upconversion Nanoparticles
Dongmei Liu, Xiumei Chen, Ze Yuan, Min Lu, Lisha Yin, Xiaoji Xie, Ling Huang
2020, 36(7): 1907011-0  doi: 10.3866/PKU.WHXB201907011
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Along with the promising applications of lanthanide doped upconversion nanomaterials in diverse fields such as biology, anti-counterfeiting, and lasering, the demand for multifunctional upconversion nanomaterials is increasing. One effective means of obtaining these nanomaterials is to fabricate upconversion nanomaterial-based heterostructures, which may provide superior properties as compared to the sum of the parts. However, obtaining heterostructured upconversion nanomaterials remains challenging mainly because of the crystal lattice mismatch between upconversion nanomaterials and other materials. Typically used strategies for synthesizing upconversion nanomaterial-based heterostructures are applicable only to limited types of materials. Alternatively, transformation of the intermediate layer is a promising strategy used to obtain these heterostructures. Nevertheless, this method remains in its infancy and, to date, only a few intermediate layers have been developed. New types of intermediate layers are therefore highly desirable. In this study, we show that amorphous Y(OH)CO3 can be a promising candidate as an intermediate layer for fabricating upconversion nanoparticle-based heterostructures. As a proof-of-concept experiment, ligand-free NaGdF4:Yb/Tm upconversion nanoparticles were first prepared as core nanoparticles. The Y(OH)CO3 shell was then directly coated on the NaGdF4:Yb/Tm upconversion nanoparticles in an aqueous solution using urea and Y(NO3)3, by a homogeneous precipitation approach. The thickness of the resulting Y(OH)CO3 shell could be tuned by adjusting the amounts of either urea or Y(NO3)3. The as-coated Y(OH)CO3 shell could be easily converted to YOF by heating at 300 ℃, yielding NaGdF4:Yb/Tm@YOF core-shell heterostructured nanoparticles. In addition, we found that the NaGdF4 core could be transformed to lanthanide oxide fluoride if the NaGdF4:Yb/Tm@Y(OH)CO3 core-shell nanoparticles were heated at 350 ℃. We also observed that treating the NaGdF4:Yb/Tm@Y(OH)CO3 core-shell nanoparticles at even higher temperatures (e.g., 400 ℃) produced aggregations of nanoparticles without regular morphologies. The transformation of the shell can be attributed to the decomposition of Y(OH)CO3 and reactions between the Y(OH)CO3 shell and NaGdF4 core. Meanwhile, the transformation of the NaGdF4 core at relatively high temperatures could be primarily due to the reactions between Y(OH)CO3 and NaGdF4. Notably, in this study, the core-shell structured nanoparticles, with either a Y(OH)CO3 or YOF shell, maintained the photon upconversion properties of NaGdF4:Yb/Tm upconversion nanoparticles. In addition, the method used here could be extended to the coating of other shells such as Tb(OH)CO3 and Yb(OH)CO3 on upconversion nanoparticles. Moreover, the NaGdF4:Yb/Tm@Y(OH)CO3 core-shell nanoparticles could be transformed to other nanoparticles with novel structures such as yolk-shell nanoparticles. These results can pave the way for preparing upconversion nanoparticle-based heterostructures and multifunctional composites, thus promoting new applications of upconversion nanoparticles.
MnCo Oxides Supported on Carbon Fibers for High-Performance Supercapacitors
Jiu Wang, Nanshi Wu, Tao Liu, Shaowen Cao, Jiaguo Yu
2020, 36(7): 1907072-0  doi: 10.3866/PKU.WHXB201907072
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The development of high-performance supercapacitor electrode materials is imperative to alleviate the ongoing energy crisis. Numerous transition metals (oxides) have been studied as electrode materials for supercapacitors owing to their low cost, environmental-friendliness, and excellent electrochemical performance. Among the developed binary transition metal oxides, manganese cobalt oxides typically show high theoretical capacitance and stable electrochemical performance, and are widely used in the electrode materials of supercapacitors. However, the poor conductivity and active material utilization of manganese cobalt oxide-based electrode materials limit their potential capacitance application. Cotton is mainly composed of organic carbon-containing materials, which can be transformed to carbon fibers after calcination. The resultant carbonaceous material exhibits a large specific surface area and good conductivity. Such advantages could potentially suppress the negative effects caused by the poor conductivity and small specific surface area of manganese cobalt oxides, thereby improving the electrochemical performance. Herein, we firstly deposited manganese cobalt oxides on cotton by a simple hydrothermal method, yielding a composite of manganese cobalt oxides and carbon fibers via subsequent calcination, to improve the electrochemical performance of the electrode material. X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET), thermogravimetric analysis (TGA), and electrochemical characterizations were used to investigate the physical, chemical, and electrochemical properties of the prepared samples. The fabricated manganese cobalt oxides in the composite were uniformly dispersed on the carbon fiber surface, which increased the contact between the interface of the electrode material and electrolyte, and enhanced electrode material utilization. The electrode material was confirmed to have well contacted with the electrolyte during a contact angle test. Hence, a pseudo-capacitance reaction completely occurred on the manganese cobalt oxide material. Moreover, the addition of carbon fibers reduced the resistance of the material, resulting in excellent capacitive performance. The capacitance of the prepared composite was 854 F∙g-1 at a current density of 2 A∙g-1. The capacitance was maintained at 72.3% after 2000 cycles at a current density of 2 A∙g-1. These results indicate that the manganese cobalt oxide and carbon fiber composite is a promising electrode material for high-performance supercapacitors. The findings presented herein provide a strategy for coupling with carbon materials to enhance the performance of supercapacitor electrode materials based on manganese cobalt oxides. Thus, novel insights into the design of high-performance supercapacitors for energy management are provided.
ZnCuAl-LDH/Bi2MoO6 Nanocomposites with Improved Visible Light-Driven Photocatalytic Degradation
Yu Guiyun, Hu Fengxian, Cheng Weiwei, Han Zitong, Liu Chao, Dai Yong
2020, 36(7): 1911016-0  doi: 10.3866/PKU.WHXB201911016
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In this study, pure Bi2MoO6 was synthesized via a solvothermal method. A ZnCuAl-layered double hydroxide (LDH)/Bi2MoO6 (denoted as LDH/Bi2MoO6) nanocomposite was synthesized via a steady-state co-precipitation route using Bi2MoO6 as the matric material. LDH was deposited on the surface of Bi2MoO6 with a close contact interface. The specific surface area of the resulting LDH/Bi2MoO6 composite increased up to 19.1 m2∙g−1 owing to the stacking arrangement between LDH and the Bi2MoO6 nanosheets, resulting in the generation of a large number of reactive sites. In addition, the light absorption region of the LDH/Bi2MoO6 composite was larger than those of pure LDH and Bi2MoO6 because of the formation of a heterojunction structure and the possible quantum size effect. The photocatalytic performance of the as-prepared samples was evaluated by carrying out the degradation of rhodamine B (RhB) using them under visible light irradiation. Compared to pure LDH and Bi2MoO6, the LDH/Bi2MoO6 nanocomposite exhibited enhanced photocatalytic activity for the degradation of RhB. With an increase in the LDH content, the photocatalytic activity of the LDH/Bi2MoO6 composite first increased and then decreased. Although the addition of an optimum amount of LDH was beneficial for the generation of electron-hole pairs, excessive LDH on the surface of Bi2MoO6 decreased the visible light absorption ability of both the components, thus reducing photocatalytic activity of the composite. This indicates that an appropriate LDH:Bi2MoO6 molar ratio is necessary for obtaining LDH/Bi2MoO6 composites with excellent photocatalytic activity. Furthermore, the LDH/Bi2MoO6 composite showed high photocatalytic stability and reusability. The structure of the LDH/Bi2MoO6 composite remained almost unchanged even after four photodegradation cycles. The enhanced photocatalytic performance of the composite can be attributed to the combined effect of its heterojunction structure and high specific surface area, which are beneficial for effective separation of photogenerated charge carriers and the availability of a large number of active sites for photocatalysis. It was found that •OH and O2•− were the main reactive species, while e and h+ contributed little to the photodegradation process. The generation, transfer, and separation of photoinduced electrons and holes in the composites were investigated by transient photocurrent responses, electrochemical impedance spectroscopy Nyquist plots, and photoluminescence measurements. The results showed that the heterojunction structure of the composites played a key role in enhancing their photocatalytic activity. A possible photodegradation mechanism was proposed for the composite. This study will provide a facile approach for the preparation of LDH- and/or Bi2MoO6-based nanocomposites. The LDH/Bi2MoO6 nanocomposite prepared in this study showed huge potential to be used as a visible-light photocatalyst for degrading environmental pollutants.
论文
基于水凝胶衍生的硅/碳纳米管/石墨烯纳米复合材料及储锂性能
安惠芳, 姜莉, 李峰, 吴平, 朱晓舒, 魏少华, 周益明
2020, 36(7): 1905034-0  doi: 10.3866/PKU.WHXB201905034
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通过氧化石墨烯(GO)和壳聚糖(Cs)之间的氢键以及静电作用形成GO水凝胶,从而将纳米硅颗粒和碳纳米管(CNT)原位包封于其中,再经冷冻干燥及随后的热处理制得三维硅/碳纳米管/石墨烯(Si-CNT@G)纳米复合材料。采用X射线衍射(XRD)、扫描电子显微镜(SEM)和透射电子显微镜(TEM)、热重分析(TGA)等技术对制得样品的物相、结构和微观形貌等进行了表征。结果表明,所得复合材料在CNT纵横交织的石墨烯网络中,均匀地分布着纳米硅颗粒。当作为锂离子电池的负极材料时,在两种碳介质的协同作用下,有效缓冲硅材料在充放电过程中脱/嵌锂引起的体积变化,缩短了锂离子和电子传输的距离,Si-CNT@G复合材料表现出较好的循环稳定性以及倍率性能。在500 mA·g−1的充放电电流密度下,经过200圈循环后,其放电比容量仍高达673.7 mAh·g1,容量保持率高达97%;即使将充放电电流密度升至2000 mA·g1时,该复合材料仍保持有566.9 mAh·g1的高可逆放电比容量。独特的制备方法和优越的储锂性能,使得Si-CNT@G纳米复合材料成为理想的高性能锂离子电池负极材料的候选.
多孔氮化钛载体上铂催化剂的原子层沉积制备及其催化氧气还原性能
唐小龙, 张盛辉, 于婧, 吕春晓, 迟雨晴, 孙君伟, 宋誉, 袁丁, 马兆立, 张立学
2020, 36(7): 1906070-0  doi: 10.3866/PKU.WHXB201906070
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为有效解决铂(Pt)催化剂用于氧气还原反应(ORR)面临的催化活性及稳定性问题,本文首先合成了具有良好导电性、电化学稳定以及耐腐蚀等优点的一维多孔氮化钛(TiN)纳米管载体材料,然后使用原子层沉积技术(ALD)在TiN载体上沉积制备了Pt催化剂(ALD-Pt/TiN),所得的Pt纳米颗粒尺寸均匀、高度分散且与TiN载体之间存在着较强的相互作用。催化氧气还原活性和稳定性测试表明,所得的ALD-Pt/TiN对ORR具有较高的催化活性,同时兼具良好的稳定性和耐久性。相比商用Pt/C,ALD-Pt/TiN的起始电位和稳态极限电流密度与其相近,半波电位则高出了20 mV,表现出优异的电催化性能。其优良的电催化性能主要归因于ALD沉积Pt纳米颗粒的高分散性,一维多孔结构TiN载体的高比表面积、良好导电性和抗腐蚀性能以及ALD-Pt与TiN载体间较强的相互作用等综合影响。本工作为设计新型高催化活性、高稳定性的Pt基催化剂提供了有益借鉴。
亮点
近红外量子点:小粒子,大能量
韩布兴
2020, 36(7): 1911025-0  doi: 10.3866/PKU.WHXB201911025
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降低“死锂”残留,提高硅负极首圈库仑效率
郭玉国
2020, 36(7): 1912010-0  doi: 10.3866/PKU.WHXB201912010
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自下而上法制备单壁碳纳米管的共轭聚合物片段:构建单一手性碳纳米管的新策略
刘忠范
2020, 36(7): 1912019-0  doi: 10.3866/PKU.WHXB201912019
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二维共价有机框架薄膜的近红外电致变色性质研究
吴凯
2020, 36(7): 1912023-0  doi: 10.3866/PKU.WHXB201912023
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低温熔融盐合成富磷相CuP2纳米材料及其储锂应用
余学斌
2020, 36(7): 1912032-0  doi: 10.3866/PKU.WHXB201912032
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团簇动态相变催化
杨金龙
2020, 36(7): 1912039-0  doi: 10.3866/PKU.WHXB201912039
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分子笼限域化学空间的超分子催化:主-客体氧化还原耦合效应实现高效可见光催化产氢
李灿
2020, 36(7): 1912041-0  doi: 10.3866/PKU.WHXB201912041
[摘要]  (14) [HTML全文] (14) [PDF 575KB] (0)
摘要:
块状和少层黑磷的合成
徐林
2020, 36(7): 1912059-0  doi: 10.3866/PKU.WHXB201912059
[摘要]  (14) [HTML全文] (14) [PDF 514KB] (1)
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全小分子有机太阳能电池:多级次形貌调控实现效率突破
李永舫
2020, 36(7): 2001011-0  doi: 10.3866/PKU.WHXB202001011
[摘要]  (14) [HTML全文] (14) [PDF 879KB] (0)
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杂原子掺杂提升四氧化三钴电催化性能
郭少军
2020, 36(7): 2001012-0  doi: 10.3866/PKU.WHXB202001012
[摘要]  (13) [HTML全文] (13) [PDF 670KB] (0)
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二维超薄CuO@SAPO-34分子筛用于催化氧化环己烷一步制己二酸
侯文华
2020, 36(7): 2001022-0  doi: 10.3866/PKU.WHXB202001022
[摘要]  (14) [HTML全文] (14) [PDF 1288KB] (0)
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前言
绚丽多彩的纳米复合材料
徐林, 侯文华
2020, 36(7): 2001015-0  doi: 10.3866/PKU.WHXB202001015
[摘要]  (16) [HTML全文] (16) [PDF 302KB] (3)
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Article
Shape-Dependent Catalytic Activity of Nano-Fe2O3 on the Thermal Decomposition of TKX-50
Ming Zhang, Fengqi Zhao, Yanjing Yang, Hui Li, Jiankan Zhang, Wenzhe Ma, Hongxu Gao, Na Li
2020, 36(6): 1904027-0  doi: 10.3866/PKU.WHXB201904027
[摘要]  (109) [HTML全文] (109) [PDF 1525KB] (109)
摘要:
Energy components used in solid rocket propellants are beneficial for improving the energy performance, and their thermal decomposition characteristics significantly affect the combustion properties of the propellants. As a kind of energetic material with both high energy and low sensitivity (impact and friction), 5, 5'-bistetrazole-1, 1'-diolate (TKX-50) can effectively improve the energy and safety characteristics of solid propellants. Burning catalyst is another important component of solid propellants, which can significantly improve the burning rate of the propellant and reduce the pressure exponent. Among various burning catalysts, nanoscale transition metal oxides can promote the thermal decomposition of the energetic component, thus enhancing the combustion properties of the solid propellant. However, the catalytic effects of nanoscale transition metal oxides with different morphologies on the thermal decomposition of TKX-50 have rarely been studied. Based on the excellent catalytic activity of Fe2O3 for TKX-50 thermal decomposition, nano-Fe2O3 particles with spherical and tubular microstructures were used for TKX-50 thermal decomposition. The Fe2O3 nanoparticles were successfully fabricated via the solvothermal method and characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS) analyses. The XRD, FT-IR, and XPS results confirmed the successful fabrication of spherical and tubular Fe2O3 samples. The SEM and TEM images showed that the spherical Fe2O3 samples are composed of agglomerated Fe2O3 nanoparticles with an average particle size of 110 nm. In addition, the average diameter and length of hollow tubular Fe2O3 nanoparticles are 120 nm and 200 nm, respectively. The catalytic activities of spherical and tubular Fe2O3 for TKX-50 decomposition were studied by thermogravimetric analysis (TG) and differential scanning calorimetry (DSC) methods. The DSC and TG-DTG curves showed that both tubular and spherical Fe2O3 could effectively promote TKX-50 thermal decomposition. The first thermal decomposition peak temperature (TFDP) of TKX-50 was reduced by 36.5 K and 26.3 K in the presence of tubular and spherical Fe2O3, respectively, at 10 K·min1. The activation energy (Ea) of TKX-50, determined by the iso-conversional method, was significantly reduced in the presence of both tubular and spherical Fe2O3. The results indicated that the microstructure of the catalyst has a significant effect on its catalytic performance for TKX-50 thermal decomposition, and that tubular Fe2O3 with hollow microstructure possesses better catalytic activity than spherical Fe2O3. The excellent catalytic activity of tubular Fe2O3 can be attributed to the hollow microstructure, which has more active sites for TKX-50 thermal decomposition.
Construction of Three-Dimensional Hematite/Graphene with Effective Catalytic Activity for the Thermal Decomposition of CL-20
Ting Zhang, Cuicui Li, Wei Wang, Zhaoqi Guo, Aimin Pang, Haixia Ma
2020, 36(6): 1905048-0  doi: 10.3866/PKU.WHXB201905048
[摘要]  (80) [HTML全文] (80) [PDF 2070KB] (80)
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High-performance solid propellants are very important for the development of modern weapons. Aside from their high energy and high burning rate, safety performance is regarded as the most important factor that should be considered whenever a new solid propellant recipe is formulated. Therefore, exploring a new type of combustion catalyst that can improve both catalytic activity and reduce the sensitivity of the energetic component is significant. Traditionally, transition metals or metal oxides are used as a combustion catalyst for accelerating the thermal decomposition of energetic components. However, the existing problem of these catalysts is the aggregation of particles accompanied by poor surface area. Coupling metal oxides with graphene is a promising approach to obtain a binary composite with stable structure and large specific surface area. In this work, rod-like and granular Fe2O3 nanoparticles were synthesized using a hydrothermal method. Then, the two as-prepared Fe2O3 nanoparticles were coupled with graphene sheets using an interfacial self-assembly method, which can effectively prevent the aggregation of Fe2O3 particles and simultaneously increase the active sites that participate in the reaction. X-ray diffraction and X-ray photoelectron spectroscopy were used to identify the phase states and chemical compositions of the prepared samples. The morphology and internal structures were further demonstrated through scanning electron microscopy, transmission electron microscopy and nitrogen adsorption-desorption tests. Both phase analysis and structure identification indicate that the prepared Fe2O3/G has high purity and high surface area. The catalytic performance of the prepared Fe2O3 and Fe2O3/G in the thermal decomposition of hexanitrohexaazaisowurtzitane (CL-20) was evaluated based on thermal gravimetric analysis-infrared spectroscopy (TGA-IR) and differential scanning calorimetry (DSC) tests. The non-isothermal decomposition kinetics of CL-20, Fe2O3/CL-20, and Fe2O3/G/CL-20 were further studied by DSC. The results reveal the excellent catalytic activity of Fe2O3/G in the thermal decomposition of CL-20, which is attributed to the presence of abundant pore structure and large surface area. The reaction mechanisms of the exothermic decomposition process of CL-20, Fe2O3/CL-20, and Fe2O3/G/CL-20 were obtained by the logical choice method, and the composites all followed same mechanism function model as CL-20. Through comparison, the rod-like Fe2O3 coupled with graphene was found to have the best catalytic activity in the thermal decomposition of CL-20. Thus, the rod-like Fe2O3 and its Fe2O3/G composite were used to investigate their influence on the impact sensitivity of CL-20 by fall hammer apparatus. The results show that rFe2O3/G can effectively decrease the impact sensitivity of CL-20 compared with pure CL-20 and rFe2O3/CL-20. Therefore, rFe2O3 coupled with graphene not only promotes the thermal decomposition but also improves the safety performance of CL-20.
Preparation of BaO·4B2O3·5H2O Nanomaterial and Evaluation of Its Flame Retardant Performance to PP by Thermal Decomposition Kinetics Method
Jing Miao, Ruifeng Guo, Zhihong Liu
2020, 36(6): 1905052-0  doi: 10.3866/PKU.WHXB201905052
[摘要]  (90) [HTML全文] (90) [PDF 760KB] (90)
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Borate is considered one of the most important additives for improving the fire-resistance of combustible polymers because of its smoke suppression, low toxicity, and good thermal stability. However, the size of prepared borate is usually in the micrometer range, which makes it difficult to disperse in a polymer matrix, thus hindering its use as fire-retardant material. The preparation and application of borate nanomaterial as flame retardant is considered an effective method. However, the preparation of barium borate nanomaterials as flame retardant has not been reported. In this paper, nanosheets and nanoribbons with different sizes for a new barium borate BaO·4B2O3·5H2O are prepared by hydrothermal method, and characterized by X-ray diffraction (XRD), Fourier transform infrared spectrum (FT-IR), thermogravimetric analysis-differential scanning calorimetry (TG-DSC), and scanning electron microscope (SEM). The flame-retardant properties of polypropylene (PP)/BaO·4B2O3·5H2O composites are investigated by thermogravimetric analysis (TG), differential scanning calorimetry (DSC) thermal analysis methods and limited oxygen index (LOI) method. Considering the near TG mass losses and the near LOI values for PP with 10% prepared BaO·4B2O3·5H2O nanosheet and nanoribbon, their flame-retardant properties need to be further evaluated by non-isothermal decomposition kinetic method. The apparent activation energy for this decomposition reaction was obtained from the slope by plotting ln(β/Tp2) against 1/Tp according to Kissinger's model. With the reduction of TG mass loss, increased heat absorption in DSC under N2 atmosphere, increased apparent activation energy Ea for the thermal decomposition of PP/BaO·4B2O3·5H2O composite as well as increased LOI value, the flame-retardant performance of prepared BaO·4B2O3·5H2O samples with PP gradually improved from bulk to nanoribbon to nanosheet. This can be attributed to the decrease in the size of BaO·4B2O3·5H2O samples because the smaller sample size leads to improved dispersion and increased contact area with the polymer. The flame-retardant mechanism is discussed by analyzing the after-flame chars of the PP/BaO·4B2O3·5H2O composite in SEM images, which show that the char layer is more compact and continuous for the PP/BaO·4B2O3·5H2O nanosheet composite. The influence of loading BaO·4B2O3·5H2O nanomaterials on the mechanical properties of PP is also tested using a universal material testing machine, in which the PP/BaO·4B2O3·5H2O nanosheet composite has higher tensile strength. The PP/BaO·4B2O3·5H2O nanosheet composite has the best flame-retardant and mechanical properties, which is promising to be developed for the application as flame-retardant material.
Synthesis, Thermal Decomposition Kinetics and Detonation Performance of a Three-Dimensional Solvent-Free Energetic Ag(I)-MOF
Chengfang Qiao, Lei Lü, Wenfeng Xu, Zhengqiang Xia, Chunsheng Zhou, Sanping Chen, Shengli Gao
2020, 36(6): 1905085-0  doi: 10.3866/PKU.WHXB201905085
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摘要:
Solvent molecules can significantly reduce the heat of detonation and stability of energetic metal-organic framework (EMOF) materials, and the development of solvent-free EMOFs has become an effective strategy to prepare high-energy density materials. In this study, a solvent-free EMOF, [Ag2(DTPZ)]n (1) (N% = 32.58%), was synthesized by reacting a high-energy ligand, 2, 3-di(1H-tetrazol-5-yl)pyrazine (H2DTPZ), with silver ions under hydrothermal conditions, and it was structurally characterized by elemental analysis, infrared spectroscopy, X-ray diffraction, and thermal analysis. In 1, the DTPZ2− ligands that adopted a highly torsional configuration bridged the Ag+ ions in an octadentate coordination mode to form a three-dimensional framework (ρ = 2.812 g∙cm−3). The large steric effect and strong coordination ability of DTPZ2− effectively prevented the solvent molecules from binding with the metal centers or occupying the voids of 1. Moreover, the strong π-π stacking interactions [centroid-centroid distance = 0.34461(1) nm] between the tetrazole rings in different DTPZ2− ligands provided a high thermal stability to the framework (Te = 619.1 K, Tp = 658.7 K). Thermal analysis showed that a one-step rapid weight loss with intense heat release primarily occurred during the decomposition of 1, suggesting potential energetic characteristics. Non-isothermal thermokinetic analyses (based on the Kissinger and Ozawa-Doyle methods) were performed using differential scanning calorimetry to obtain the thermoanalysis kinetic parameters of the thermodecomposition of 1 (Ea = 272.1 kJ·mol−1, Eo = 268.9 kJ·mol−1; lgA =19.67 s−1). The related thermodynamic parameters [enthalpy of activation (ΔH = 266.9 kJ·mol−1), entropy of activation (ΔS = 125.4 J·mol−1·K−1), free energy of activation (ΔG = 188.3 kJ·mol−1)], critical temperature of thermal explosion (Tb = 607.1 K), and self-accelerating decomposition temperature (TSADT = 595.8 K) of the decomposition reaction were also calculated based on the decomposition peak temperature and extrapolated onset temperature when the heating rate approached zero. The results revealed that 1 featured good thermal safety, and its decomposition was a non-spontaneous entropy-driven process. The standard molar enthalpy for the formation of 1 was calculated to be (2165.99 ± 0.81) kJ·mol−1 based on its constant volume combustion energy determined using a precise rotating oxygen bomb calorimeter. Detonation and safety performance tests revealed that 1 was insensitive to impact and friction, and its heat of detonation (10.15 kJ·g−1) was higher than that of common ammonium nitrate explosives, such as octogen (HMX), hexogene (RDX), and 2, 4, 6-trinitrotoluene (TNT), indicating that 1 is a promising high-energy and insensitive material.
综述
生物热化学和热动力学研究进展
谢文, 周莲娇, 徐娟, 郭清莲, 蒋风雷, 刘义
2020, 36(6): 1905051-0  doi: 10.3866/PKU.WHXB201905051
[摘要]  (94) [HTML全文] (94) [PDF 1037KB] (94)
摘要:
生命相关过程伴随着极其复杂的化学和物理过程,包含着物质变化和能量转换,其中部分能量不可避免地会以热的形式表现出来。用微量热技术和热动力学方法,研究复杂生命体系和相关反应的热动力学过程,可宏观地、本质地反映生命相关过程的内在规律。本文综述了生物量热学方法和技术在生命科学中的应用,介绍了生物量热技术在生态系统、生物组织和器官、细胞水平、亚细胞水平和分子层面等不同生物层次和结构水平上的研究现状和进展。
热分析动力学研究方法的新进展
任宁, 王昉, 张建军, 郑新芳
2020, 36(6): 1905062-0  doi: 10.3866/PKU.WHXB201905062
[摘要]  (75) [HTML全文] (75) [PDF 433KB] (75)
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“非等温动力学”作为热分析动力学研究的核心,已经被广泛应用于化学、化工、冶金、地质、药物和环保等重要领域。热分析动力学研究的主要任务是确定机理函数、活化能和指前因子等动力学参数。在众多的热分析动力学研究方法中,“等转化率法”由于其可以在不涉及动力学模式函数的前提下,获得较为可靠的活化能值,因此被国际热分析与量热学协会(ICTAC)推荐使用。本文简要介绍了近十年来提出的热分析动力学研究方法,特别是等转化率方法的研究进展情况,评述了各种方法的特点与局限。同时,展望了热分析动力学研究方法未来的发展趋势。
超快扫描量热技术表征高分子结晶动力学
何裕成, 谢科锋, 王优浩, 周东山, 胡文兵
2020, 36(6): 1905081-0  doi: 10.3866/PKU.WHXB201905081
[摘要]  (78) [HTML全文] (78) [PDF 1804KB] (78)
摘要:
高分子结晶行为是高分子材料加工过程研究的热点,因为高分子组分和加工工艺控制着高分子结晶及其产物性能。差示扫描量热仪(DSC)是研究高分子结晶动力学常规手段。但是,普通DSC所能达到的最快降温速率一般无法抑制较快的样品结晶,结晶行为将在等温结晶动力学测试之前发生,因此可进行等温结晶的研究温度范围局限于较低结晶过冷度的高温区域。近年来,具有超快速升降温扫描速率和精准控温的快速扫描芯片量热仪(FSC,其商业化版本Flash DSC 1)得到了广泛应用。FSC可以抑制高分子样品在升降温过程中的结晶成核,避免对之后的结晶动力学测试产生影响。因此FSC技术将高分子结晶动力学的研究温度区间延伸至具有较大过冷度的低温区,加深了我们对高分子结晶成核机理以及高分子工业加工过程的理解。本文首先介绍了由初级成核方程描述的高分子结晶动力学原理,初级成核自由能位垒(ΔG*)和扩散活化能位垒(ΔU)分别控制了高低温区的结晶动力学。我们还总结了FSC技术的发展,包括氮化硅薄膜芯片技术、快速扫描量热仪、商业化Flash DSC 1在不同高分子结晶熔融行为研究中的应用。然后介绍表征高分子等温结晶动力学的方法,其中包括样品制备、质量估算、消除热历史、临界扫描速率的确定等,并举例介绍FSC在高分子结晶动力学研究中的应用,涵盖高分子总结晶动力学、结晶成核动力学、高分子焓松弛对结晶成核的影响、FSC联用技术等方面。应用举例中对应形貌和结晶信息,分析了通过FSC测试得到的结晶成核动力学特点。另外通过比较不同结构特点的高分子,总结了我们对结晶动力学行为的基本理解。总之,FSC技术是一种能够提供相转变动力学和热力学信息的高效工具,特别是应用于分析只能在快速扫描中得到的样品结构变化信息。同时我们希望本文能够帮助读者考虑超快扫描量热技术在其他材料研究上的应用,包括合金、药物、生物大分子等。
论文
基于光微热量-荧光光谱联用技术研究光催化热力学和动力学的温度效应
覃方红, 万婷, 邱江源, 王一惠, 肖碧源, 黄在银
2020, 36(6): 1905087-0  doi: 10.3866/PKU.WHXB201905087
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摘要:
利用光微热量-荧光光谱联用技术,对光催化过程的热谱和光谱信息同步监测,获取了五个温度下,g-C3N4@Ag@Ag3PO4光催化降解罗丹明B的原位热动力学、光谱动力学信息,探究了温度对相关参数的影响。结果表明,催化降解反应分为三个阶段:(ⅰ)污染物和催化剂的光响应过程;(ⅱ)光响应吸热和污染物降解放热的竞争过程;(ⅲ)保持稳定的放热率。吸热和放热的竞争过程符合一级动力学,降解速率随着温度的升高而增大;稳定放热阶段为拟零级反应,在283.15 K、288.15 K、293.15 K、298.15 K、303.15 K下的放热速率分别为0.4668 ± 0.3875 μJ∙s−1、0.5314 ± 0.3379 μJ∙s−1、0.5064 ± 0.3234 μJ∙s−1、0.5328 ± 0.3377 μJ∙s−1、0.5762 ± 0.3452 μJ∙s−1。本研究为探究光催化过程的原位热力学、热动力学及光谱信息及机理的推测提供科学依据。
纳米白藜芦醇脂质体的制备及分配系数测定
张茹, 元琳琳, 孙凯玥, 王珊, 耿丽娜, 张建军
2020, 36(6): 1905090-0  doi: 10.3866/PKU.WHXB201905090
[摘要]  (78) [HTML全文] (78) [PDF 789KB] (78)
摘要:
采用薄膜旋转蒸发-超声法制备了纳米白藜芦醇脂质体(RES-Lip),并用透射电子显微镜(TEM)和动态光散射技术(DLS)对产物进行表征;测定了膜材比(卵磷脂与胆固醇质量比mPC : mChol = 5 : 1,8 : 1,10 : 1,12 : 1)和药脂比(药物与卵磷脂质量比mRES : mPC = 1 : 25,1 : 40,1 : 50,1 : 60)对RES-Lip脂质体-水分配系数(Plip/w)的影响,以及油-水分配系数(lgPo/w)和脂质体-水分配系数(lgPlip/w)随pH值的变化趋势,计算了RES-Lip中药物与磷脂双分子膜之间的吉布斯自由能。结果表明,实验中所制备的RES-Lip呈球形囊泡结构,粒径约为100 nm;当膜材比和药脂比分别为10 : 1和1 : 40时,lgPlip/w最大,说明此时RES与磷脂膜间的综合作用力最大;RES-Lip的分配系数(lgPo/w和lgPlip/w)随体系pH的变化趋势相同,说明RES与磷脂膜的作用力中以疏水作用为主,氢键、静电作用为辅;RES-Lip中RES与脂质体膜之间的吉布斯自由能为−17.07 kJ∙mol−1
SDS对SB3-12胶束表面电荷密度的调控作用及对药物增溶的影响
邢肇碧, 过治军, 张雨微, 刘君玲, 王玉洁, 白光月
2020, 36(6): 1906006-0  doi: 10.3866/PKU.WHXB201906006
[摘要]  (79) [HTML全文] (79) [PDF 763KB] (79)
摘要:
两性离子甜菜碱表面活性剂(SB3-12)胶束具有较好的生物相容性,由于相反电荷的极性头之间具有静电中和作用,胶束表面具有小的负电荷密度。当加入阴离子的十二烷基硫酸钠(SDS)以后,负离子SD与SB3-12胶束极性区内层季铵正电荷的静电中和作用,能连续地调节胶束表面磺酸基的负电荷密度,这有利于对药物分子的选择性增溶和调节在生理条件下的药物的输送。等温滴定量热(ITC)研究发现SB3-12和SDS有强的协同效应,混合临界胶束浓度(CMC)和胶束化焓明显降低,并得到两者协同效应的弱静电作用机理。当模型药物分子芦丁(Rutin)与SB3-12/SDS混合胶束作用时,芦丁7位羟基的氢解离后的阴离子与SDS共同作用于SB3-12形成混合胶束。UV-Vis吸收光谱和1H NMR谱研究发现,在SB3-12胶束中,芦丁分子的A环位于季铵阳离子附近,B环位于两个相反电荷之间的弱极性区域。在SDS胶束中,B环位于栅栏层,而A环和二糖暴露于水相侧。在混合胶束中,随着SDS摩尔分数增加,对A环的静电吸引变弱。离子表面活性剂对两性离子表面活性剂胶束表面电荷密度的调节作用,本质上是对胶束极性区域的物理及化学性质的微调,进而实现对药物的可控增溶。
亮点
Cr2O3/硝化棉的相容性及热分解机理研究
韩布兴
2020, 36(6): 1907020-0  doi: 10.3866/PKU.WHXB201907020
[摘要]  (80) [HTML全文] (80) [PDF 369KB] (80)
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Flash DSC跨界表征材料的热导率
张建军
2020, 36(6): 1907048-0  doi: 10.3866/PKU.WHXB201907048
[摘要]  (66) [HTML全文] (66) [PDF 308KB] (66)
摘要:
前言
热分析动力学与热动力学
王键吉, 张建军
2020, 36(6): 1909020-0  doi: 10.3866/PKU.WHXB201909020
[摘要]  (80) [HTML全文] (80) [PDF 194KB] (80)
摘要:

编委会

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《物理化学学报》第4届编委会

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名誉主编

唐有祺

北京大学

顾问编委

包信和

中国科学院大连化学物理研究所

段雪

北京化工大学

付贤智

福州大学

侯建国

中国科学技术大学

黄维

南京工业大学

LIEBER Charles M.

Harvard University

田中群

厦门大学

万立骏

中国科学院化学研究所

吴云东

北京大学

谢晓亮

Harvard University, 北京大学

杨伟涛

 Duke University

姚建年

中国科学院化学研究所

赵新生

北京大学

主编

刘忠范

北京大学

副主编

韩布兴

中国科学院化学研究所

刘鸣华

国家纳米科学中心

申文杰

中国科学院大连化学物理研究所

吴凯

北京大学

杨金龙

中国科学技术大学

庄林

武汉大学

迟力峰

苏州大学

编委

曹勇

复旦大学

陈经广

University of Delaware

陈军

南开大学

崔屹

Stanford University

邓风

中国科学院武汉物理与数学研究所

邓友全

中国科学院兰州化学物理研究所

樊卫斌

中国科学院山西煤炭化学研究所

房喻

陕西师范大学

付红兵

中国科学院化学研究所

傅强

中国科学院大连化学物理研究所

高毅勤

北京大学

郭林

北京航空航天大学

郝京诚

山东大学

侯文华

南京大学

金荣超

Carnegie Mellon University

来鲁华

北京大学

李朝军

McGill University

李隽

清华大学

李象远

四川大学

梁万珍

厦门大学

刘海超

北京大学

刘洪来

华东理工大学

刘述斌

University of North Carolina

刘义

武汉大学

刘志敏

中国科学院化学研究所

罗小民

中国科学院上海药物研究所

马晶

南京大学

孟庆波

中国科学院物理研究所

邵翔

中国科学技术大学

孙俊奇

吉林大学

谭蔚泓

湖南大学

唐智勇

国家纳米科学中心

王键吉

河南师范大学

王鹏

中国科学院长春应用化学研究所

王心晨

福州大学

王永锋

北京大学

魏子栋

重庆大学

翁羽翔

中国科学院物理研究所

吴鹏

华东师范大学

夏永姚

复旦大学

许国勤

National University of Singapore

杨俊林

国家自然科学基金委员会

余家国

武汉理工大学

尉志武

清华大学

占肖卫

北京大学

张东辉

中国科学院大连化学物理研究所

张浩力

兰州大学

张锦

北京大学

章俊良

上海交通大学

周永贵

中国科学院大连化学物理研究所

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发布时间: 2018-05-02


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发布日期:2009-06-24 浏览: