首页 > 期刊 > 物理化学学报

  

综述
钠离子电池电极材料的设计策略——固态离子学视角
傅焰鹏, 朱昌宝
2023, 39(3): 2209002-0  doi: 10.3866/PKU.WHXB202209002
[摘要]  (9) [HTML全文] (9) [PDF 3153KB] (0)
摘要:
钠离子电池是目前最有前景及可行性的新兴储能候选体系。对于钠离子电池而言,如何实现其电极材料的理性设计及构筑,是重要的科学问题。本文立足于钠离子/电子输运这一核心问题,从固态离子学视角探讨钠离子电池电极材料的设计策略。首先,对于体相电极材料,输运特性的明晰、调控以及缺陷化学模型的建立,是传统电极材料开发的关键。其次,对于纳米电极材料,随着尺寸的减小,电极材料的热力学性质、动力学特性以及钠离子微观储输机制都会发生相应变化,因此从纳米离子学视角,以尺寸效应调控电极材料具有重要的科学价值及现实意义。最后,无论对于体相材料还是纳米材料,从材料的本征输运特性出发,通过电化学电路的设计和构筑来优化电极动力学,可以为钠电电极材料的理性设计及可控制备提供理论指导。我们相信,通过本文系统地对钠离子电池电极材料设计策略的梳理,必将对钠离子电池的开发,提供有意义的指导,并为最终的产业化打下良好的基础。
四维扫描透射电子显微镜技术:从材料微观结构到物性分析
冯启龙, 朱翀之, 盛冠, 孙土来, 李永合, 朱艺涵
2023, 39(3): 2210017-0  doi: 10.3866/PKU.WHXB202210017
[摘要]  (3) [HTML全文] (3) [PDF 1387KB] (0)
摘要:
扫描透射电子显微镜(Scanning transmission electron microscopy,STEM)目前已经达到了原子级分辨率,并且由于其具有灵活的多通道成像能力以及强大的与谱学分析相结合的特点,因此在材料科学、生命科学等领域展现出强大的微尺度表征能力。但传统STEM的探测器受单像素积分式探测机制的限制,使其只能收集特定角度的散射电子,这导致不仅丢失了散射电子的角分辨信息,还降低了入射电子的剂量效率,因此迫切需要发展全新成像技术来实现高通量、高电子剂量效率成像。近年来,电子探测技术和分区或像素化探测器的研发联合计算机运算、存储能力的大幅提高,推动了四维扫描透射电子显微镜技术(Four-dimensional scanning transmission electron microscopy,4D-STEM)的蓬勃发展,并为最大化、最高效挖掘散射电子信息带来希望。在采集4D-STEM数据时,会聚电子束在样品平面上进行二维扫描,与此同时使用一块具有高帧速、高动态范围以及高信噪比的像素化阵列式探测器在远场收集二维的衍射数据。因为这些衍射数据是角度解析的,所以既可以用来进行常规的STEM成像,也可以用来实现前沿的相位衬度成像。例如利用电子叠层重构(Ptychography)技术通过在不同空间位置测量的一系列衍射花样来重建样品物函数。此外,4D-STEM技术还可以被进一步挖掘从而获得更多关于材料内部结构的信息,这为材料的多尺度表征带来机会。本文从4D-STEM技术原理介绍开始,总结了4D-STEM技术从材料微观结构到物性分析方面的一系列应用。具体而言,内容包含了虚拟探测器成像、微区电磁场测量、微区晶体取向测量、微区应变分布测量以及材料局域厚度测量等材料微尺度表征方面的原理和应用。除此之外,利用4D-STEM数据实现的电子叠层重构成像技术因为具有较高的散射电子利用效率,所以在低电子剂量领域展现出极大的应用潜力,因此本文还对4D-STEM技术在低电子剂量领域的应用进行了探讨与展望。总而言之,随着电子探测器以及4D-STEM数据后处理分析软件的快速发展,相信新颖的4D-STEM技术最终将彻底取代传统的扫描透射电子显微镜。
高比能钠离子电池预钠化技术研究进展
徐铭礼, 刘猛闯, 杨泽洲, 吴晨, 钱江锋
2023, 39(3): 2210043-0  doi: 10.3866/PKU.WHXB202210043
[摘要]  (4) [HTML全文] (4) [PDF 2076KB] (1)
摘要:
钠离子电池有望取代锂离子电池实现大规模储能应用。然而,储钠负极材料具有较低的初始库伦效率,制约了高比能钠离子电池的开发。预钠化技术被认为是补偿负极活性钠损失、提升电池能量密度的最直接有效的方法,对于钠离子电池的商业化应用具有重要意义。本文全面总结近年来预钠化技术的最新研究进展,包括短接法预钠化、电化学预钠化、钠金属物理预钠化、化学预钠化和正极补钠添加剂等,并从反应原理、安全性、可操作性、处理效率和可放大性等角度分析讨论现有各技术方案的优势及面临的挑战;着重介绍化学预钠化和正极补钠添加剂,这两类最具应用前景的预钠化技术的最新成果,进而从实用化角度深入探讨仍待解决的科学问题和技术难点。本文可为预钠化技术的进一步优化和高比能钠离子电池的开发提供思路。
Article
High-Throughput Synthesis and Screening of Pt-Based Ternary Electrocatalysts Using a Microfluidic-Based Platform
Yang Hu, Bin Liu, Luyao Xu, Ziqiang Dong, Yating Wu, Jie Liu, Cheng Zhong, Wenbin Hu
2023, 39(3): 2209004-0  doi: 10.3866/PKU.WHXB202209004
[摘要]  (9) [HTML全文] (9) [PDF 2160KB] (0)
摘要:
Pt-based electrocatalysts have received extensive attention owing to their wide applications in various fields, including fuel cells, hydrogen production, degradation of organic pollutants, electrochemical sensors, and oxidation of small molecules. Therefore, the efficient synthesis and screening of high-performance Pt-based electrocatalysts is necessary for accelerating their further development and application in these fields. The conventional method for developing the advanced materials and optimizing their synthesis parameters is time-consuming, inefficient, and costly. Microfluidic high-throughput techniques have the great potential for optimizing the synthesis parameters of Pt-based electrocatalysts. However, microfluidic high-throughput synthesis without performance evaluation cannot maximize its advantages. Therefore, it is highly desirable to develop a platform that combines the high-throughput synthesis of materials and the evaluation of their properties in a high-throughput fashion to improve the overall screening efficiency of the novel materials. In this study, a versatile microfluidic high-throughput platform, combining the high-throughput synthesis and screening of materials, was constructed. The microfluidic chip generated 20-level concentration gradients of the three different precursors. Microreactor arrays with 100 microchannels were used for the material synthesis and electrochemical characterization. A wide range of concentration combinations of the three different precursor solutions was achieved using the microfluidic chip. Five groups of Pt-based ternary electrocatalysts (100 different components in total) were synthesized and electrochemically characterized using the designed platform. The obtained Pt-based electrocatalysts exhibited a loose particle morphology, and were composed of small nanoparticles. The efficient preparation of Pt-based electrocatalysts with controllable compositions was also achieved through the high-throughput synthesis platform. The catalytic performance of the Pt-based catalysts towards oxygen evolution reaction (OER) was characterized by chronoamperometry. The optimal composition of Pt-based ternary electrocatalysts for OER was directly determined using the designed platform. For NiPtCu, the samples with a relatively high atomic percentage (approximately 50%) of Pt (i.e., Ni0.30Pt0.56Cu0.14, Ni0.17Pt0.52Cu0.31 and Ni0.12Pt0.48Cu0.40) exhibited higher electrocatalytic activity and stability, whereas the samples with a relatively high atomic percentage (> 50%) of Cu possessed lower activity and stability. For AuPtNi and AuPtCu, the samples wherein Au and Pt accounted for a large proportion of the sample (i.e., Ni or Cu < 10%) and the atomic ratios of Au : Pt were (3–4) : 1, e.g., Au0.71Pt0.25Ni0.04 and Au0.77Pt0.18Cu0.05, displayed high electrocatalytic activity and stability. As the atomic fraction of Au decreased, the atomic ratio of Pt and Ni in AuPtNi approached 3 : 1 or that of Pt and Cu in AuPtCu reached to 1 : 1, the samples (Au0.54Pt0.35Ni0.11, Au0.35Pt0.42Cu0.23, Au0.27Pt0.41Cu0.32 and Au0.12Pt0.32Cu0.56) all demonstrated high electrocatalytic activity and stability. The samples (Pt0.06Cu0.94) wherein the atomic percentages of Au and Pt were all less than 10%, exhibited poor electrocatalytic activity and stability. For RhPtNi and RhPtCu, when the atomic percentage of Rh in RhPtNi and RhPtCu was high (50%–90%) and almost no Ni or Cu was present, the samples (Rh0.91Pt0.09 and Rh0.82Pt0.18 for RhPtNi, as well as Rh0.88Pt0.12 and Rh0.75Pt0.21Cu0.04 for RhPtCu) all had high electrocatalytic activity and stability. As the atomic percentage of Rh decreased and that of Pt increased, the atomic percentages of Rh and Pt were relatively close, Rh0.54Pt0.32Ni0.14 and Rh0.51Pt0.36Cu0.14 showing high electrocatalytic activity and stability. When the atomic percentages of Ni and Cu were high (> 50%), the RhPtNi and RhPtCu samples all showed the relatively poor electrocatalytic activity and stability. These results demonstrate the high efficiency and flexibility of the constructed microfluidic high-throughput platform, which significantly shortens the cycle for the development cycle of new materials and the optimization of their properties.
Water Steam Bathed FeS2 for Highly Efficient Fenton Degradation of Alachlor
Jizhou Jiang, Lianglang Yu, Fangyi Li, Wenming Deng, Cong Pan, Haitao Wang, Jing Zou, Yaobin Ding, Fengxia Deng, Jia Huang
2023, 39(3): 2209033-0  doi: 10.3866/PKU.WHXB202209033
[摘要]  (6) [HTML全文] (6) [PDF 3433KB] (0)
摘要:
Fenton-like activity of iron sulfides for the generation of reactive oxygen species and degradation of various organic pollutants has been extensively investigated due to its abundance in the natural environment. However, their Fenton-like activity is usually unsatisfactory due to the limited exposure of surface ferrous reactive sites. In this work, a new strategy to enhance the Fenton-like activity of iron sulfides, using pyrite (FeS2) as a model, was developed based on the heat treatment of FeS2 by water steam. It was found that the FeS2 heat-treated by water steam (Heat-FeS2) exhibited much higher heterogeneous Fenton activity in the degradation of alachlor (ACL) than its parent FeS2 prepared from hydrothermal reaction (Fresh-FeS2). At an initial pH of 6.3, the rate of degradation of ACL by Heat-FeS2 Fenton system was 0.48 min−1, which is ~23 times higher than that of Fresh-FeS2 Fenton system. Electron spin resonance analysis and benzoic acid probe experiments confirmed the production of more hydroxyl (•OH) and superoxide radicals (•O2) in Heat-FeS2 Fenton system than Fresh-FeS2 Fenton system. The increased Fenton-like activity of Heat-FeS2 can be attributed to the increased content of highly reactive surface bonded Fe2+/Fe3+ species, higher amount of leached Fe2+, and optimal reaction pH due to stronger acidification of Heat-FeS2. Characterization studies by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared spectroscopy showed that heat treatment remarkably promoted the transformation of lattice Fe2+ to surface reactive Fe2+, allowing the exposure of more surface reactive Fe2+ and leaching of Fe2+; simultaneously, heat treatment enhanced the generation of surface SO42−, creating a highly acidic surface. The surface Fe2+ percentage in the surface total iron was raised from 13% in Fresh-FeS2 to 29% in Heat-FeS2. Fe2+ leaching from Heat-FeS2 was 0.23 mmol·L−1, much higher than that (< 0.02 mmol·L−1) for Fresh-FeS2. The change in the surface Fe and S species in the Heat-FeS2 system during the Fenton-like reaction was monitored by XPS to elucidate the enhanced Fenton oxidation mechanism. The characterization results showed that after Fenton reaction with H2O2, the surface contents of Fe2+ and Fe3+ species on Fresh-FeS2 and Heat-FeS2 were remarkably raised, while the surface content of S22− species was reduced, confirming the crucial role of S22− in the reductive cycle of Fe3+ to Fe2+. These findings increase understanding of the oxidative transformation and corrosion of iron sulfides and its relevant transformation and degradation of toxic organics in natural environments. The results of this work also provide an efficient Fenton-like oxidation method based on iron sulfides for highly efficient degradation of organic pollutants (e.g. ACL) in aqueous solution.
Colloidal Quantum Dot Solids with a Diminished Epitaxial PbI2 Matrix for Efficient Infrared Solar Cells
Mingxu Zhang, Qisen Zhou, Xinyi Mei, Jingxuan Chen, Junming Qiu, Xiuzhi Li, Shuang Li, Mubing Yu, Chaochao Qin, Xiaoliang Zhang
2023, 39(3): 2210002-0  doi: 10.3866/PKU.WHXB202210002
[摘要]  (9) [HTML全文] (9) [PDF 4133KB] (0)
摘要:
Colloidal quantum dots (CQDs) are extremely promising infrared optoelectronic materials for efficient solar cells owing to their strong infrared absorption with tunable spectra. However, the liquid-state ligand exchange of CQDs using ammonium acetate (AA) as an additive generally resulted in intensive charge-transport barriers within the CQD solids. This is induced by the high-bandgap PbI2 matrix, which considerably affects the charge-carrier extraction of CQD solar cells (CQDSCs), and thus their photovoltaic performance. Herein, dimethylammonium iodide (DMAI) was used as an additive instead for the liquid-state ligand exchange, substantially eliminating the PbI2 matrix capping the CQDs and simultaneously restraining CQD fusion during the ligand exchange, thereby reducing the barriers for the charge-carrier transport within the CQD solids. Extensive experimental studies and theoretical calculations were performed to link the surface chemistry of the CQDs with the charge-carrier dynamics within the CQD solids and full solar cell devices. The theoretical calculation results reveal that DMAI which possess small dissociation energy could finely regulate the ligand exchange of CQDs, resulting in the suppressed energetic disorder and diminished charge-transport barriers in the CQD solids compared to those of the CQD solids prepared using AA. The DMAI-treated quantum dots were characterized and analyzed by transmission electron microscopy, X-ray photoelectron spectroscopy, and 2D grazing-incidence wide-and small-angle X-ray scattering spectrometry. The results show PbI2-related Bragg peaks in the AA-treated CQD solid films, indicating a thick layer of PbI2 crystal matrix being formed in the CQD solids, whereas there was no obvious PbI2 signal observed in DMAI-treated CQD solids. These results also demonstrate that DMAI provides additional I, improving the surface passivation of the CQDs and reducing trap-assisted recombination. For the infrared photovoltaic applications, the CQDSC devices were fabricated, which shows that the photovoltaic performance of CQDSCs was significantly improved. The power conversion efficiency of DMAI-based CQDSCs was improved by 17.8% compared with that of the AA-based CQDSC. The charge-carrier dynamics in both CQD solids and full solar cell devices were analyzed in detail, revealing that the improved photovoltaic performance in DMAI-based CQDSCs was attributed to the facilitated charge-carrier transport within the CQD solids and suppressed trap-assisted recombination, resulting from eliminated charge-transport barriers and improved surface passivation of CQDs, respectively. This work provides a new avenue to controlling the surface chemistry of infrared CQDs and a feasible approach to substantially diminishing the charge transfer barriers of CQD solids for infrared solar cells.
RGO-Coated MOF-Derived In2Se3 as a High-Performance Anode for Sodium-Ion Batteries
Haoliang Lv, Xuejie Wang, Yu Yang, Tao Liu, Liuyang Zhang
2023, 39(3): 2210014-0  doi: 10.3866/PKU.WHXB202210014
[摘要]  (8) [HTML全文] (8) [PDF 3798KB] (0)
摘要:
MOF-derived metal selenides are promising candidates as effective anode materials in sodium-ion batteries (SIBs) owing to their ordered carbon skeleton structure and the high conductivity of selenides. They can be imparted with rapid electron/ion transport channels for the insertion/de-insertion of Na+. In this study, MOF-derived In2Se3 was prepared as an anode material for SIBs. However, the large volume expansion during cycling leads to structural collapse, which affects the charging and discharging circulation life of the battery. To address this, a two-dimensional rGO network was introduced on the MOF-derived In2Se3 surface by surface modification. Field-emission scanning electron microscopy (FE-SEM) and X-ray photoelectron spectroscopy (XPS) results confirmed the successful synthesis of the In2Se3@C/rGO composite. The structures with two types of carbon enhanced the charge transfer kinetics and provided two stress-buffering layers. Thus, the volume change could be accommodated and simultaneously, electron transfer was accelerated. This technique was effective, as proved by the enhanced capacity retention of 95.2% at 1 A·g−1 after 500 cycles. In contrast, the capacity retention of the MOF-derived material without rGO was only 74.2%. Additionally, due to the synergistic effect of the rGO network and the MOF-derived In2Se3, the anode showed a superior capacity of 468 mAh·g−1 at 0.1 A·g−1. Conversely, at the same current density, the uncoated material delivered only a capacity of 393 mAh·g−1. To study the electrochemical process of the electrode, the In2Se3@C/rGO electrode was subjected to cyclic voltammetry (CV) measurements; the results showed that the In2Se3@C/rGO electrode had notable electrochemical reactivity. In addition, in situ X-ray diffraction (XRD) was performed to explore the sodium storage mechanism of In2Se3, demonstrating that In2Se3 had a dual Na+ storage mechanism involving conversion and alloying reactions, and revealing the origin of its high theoretical specific capacity. This study is expected to serve as a reference for preparing optimized rGO-based materials for use as SIB anodes.
展望
碳酸盐炼制共热耦合甲烷干重整制高附加值化学品发展展望
尹倩, 宋慧婷, 徐明, 鄢红, 赵宇飞, 段雪
2023, 39(3): 2210026-0  doi: 10.3866/PKU.WHXB202210026
[摘要]  (5) [HTML全文] (5) [PDF 2323KB] (0)
摘要:
传统过程工业,诸如我国水泥、钢铁、耐材和电石等行业,都涉及碳酸盐高温热分解过程,其导致的CO2排放量超过了全国工业碳排放总量的50%,大量CO2排放对全球气候产生了不可逆转的影响。因此,如何减少过程工业排放的CO2并且充分利用碳酸盐热分解的余热面临着巨大挑战。为进一步降低该类过程工业的CO2排放量同时降低其热分解的能耗,通过利用地球上储量丰富的温室气体CH4,对碳酸盐进行共热耦合重整制备合成气等高附加值产品,有望成为一种环保经济的技术路线。本文总结了(光/热)碳酸盐炼制耦合甲烷干重整反应、醇类重整反应以及CO2捕获反应的最新进展,并且对碳酸盐炼制耦合甲烷干重整反应在理论计算方面的研究进展进行了介绍,进一步结合本课题组近期关于碳酸盐共热耦合甲烷重整的最新结果,我们提出了该类耦合反应的发展展望,为实现CO2的高效转化和减排增效提供了思路。
评论
基于模糊集合的评审决策信息融合
王璐, 李根梓, 戴亚飞, 付雪峰
2023, 39(3): 2210029-0  doi: 10.3866/PKU.WHXB202210029
[摘要]  (5) [HTML全文] (5) [PDF 806KB] (0)
摘要:
同行评议是评价、评审和评估等活动的重要实施方式,尤其对于科学基金项目的评审,同行评议是保证项目质量的有效措施。同行评议过程中固有的模糊属性,会导致评审结果在一定程度上偏离被评价对象的内在价值。本文针对同行评议的模糊属性,提出一种评审决策信息融合的方法,通过对专家评分进行关联分析和自适应调整,实现评审结果围绕被评价对象的内在价值等关键指标达成共识,助力科学基金的评审机制改革和评审决策的智能化。

论文
碱性聚合物电解质膜的表面锥形阵列结构提升燃料电池性能
张婧雯, 马华隆, 马军, 胡梅雪, 李启浩, 陈胜, 宁添姝, 葛创新, 刘晰, 肖丽, 庄林, 张熠霄, 陈立桅
2023, 39(2): 2111037-0  doi: 10.3866/PKU.WHXB202111037
[摘要]  (217) [HTML全文] (217) [PDF 2530KB] (217)
摘要:
燃料电池作为一种清洁高效的能量转换装置,被认为是构建未来社会可再生能源结构的关键一环。不同于质子交换膜燃料电池(PEMFC),碱性聚合物电解质燃料电池(APEFC)的出现使非贵金属催化剂的使用成为可能,因而受到了日益广泛的关注和研究。APEFC的关键结构是膜电极,主要由聚合物电解质膜和阴阳极(含催化层、气体扩散层)组成,膜电极是电化学反应发生的场所,其优劣直接决定着电池性能的好坏。因此,基于现有的碱性聚合物电解质及催化剂体系,如何构筑更加优化的膜电极结构,使APEFC发挥出更高的电池性能是亟待开展的研究。本文首先通过模板法在碱性聚合物电解质膜的表面构建出有序的锥形阵列,再将具有阵列结构的一侧作为阴极来构筑膜电极,同时,作为对比,制备了由无阵列结构的聚合物电解质膜构筑而成的膜电极,最后对基于两种不同膜电极的APEFC的电化学性能进行了对比研究。实验结果表明,锥形阵列结构可以将APEFC的峰值功率密度由1.04 W·cm−2显著提高到1.48 W·cm−2,这主要归因于在APEFC的阴极侧具有锥形阵列结构的聚合物电解质膜的亲水性的提升和催化剂电化学活性面积的增加。本工作为碱性聚合物电解质燃料电池的膜电极结构设计与优化提供了新思路。
高安全锂离子电池复合集流体的界面强化
汪茹, 刘志康, 严超, 伽龙, 黄云辉
2023, 39(2): 2203043-0  doi: 10.3866/PKU.WHXB202203043
[摘要]  (200) [HTML全文] (200) [PDF 4788KB] (200)
摘要:
面向高能量密度电池的高比容量三元正极材料的应用,使锂离子电池更容易发生热失控,这不仅降低了其安全性, 也限制了锂离子电池的进一步发展。如何在提高能量密度的同时保证电池的安全性是亟待解决的问题。以绝缘高分子薄膜为支撑基材,两侧沉积金属层得到了具有夹芯结构的铝复合集流体能有效保证电池在针刺条件下的安全性,且更轻的复合集流体的使用能进一步提高电池能量密度。但高分子基材与铝金属层之间界面结合力较差,这会导致复合集流体在高温电解液浸泡中发生脱层现象,从而影响其在电池中的使用。本研究采用聚对苯二甲酸乙二醇酯(PET)作为支撑基材,通过在铝金属镀层与高分子基材之间引入氧化物中间层,有效地增强了金属与高分子基材之间的界面结合力,提升复合集流体的电解液兼容性。此外,复合集流体良好的机械性能使其能很好地兼容现有的电池制备技术,利用其制备的软包电池表现出与使用传统铝箔为集流体的电池相当的电化学性能。进一步的针刺测试表明,复合集流体能有效阻止锂电池在针刺过程中的热失控,显著改善了电池的安全性能。
微秒时间分辨的工况电化学紫外可见吸收光谱测量系统
尉瑞芳, 李东峰, 尹恒, 王秀丽, 李灿
2023, 39(2): 2207035-0  doi: 10.3866/PKU.WHXB202207035
[摘要]  (186) [HTML全文] (186) [PDF 715KB] (186)
摘要:
工况光谱表征技术是深入理解电催化反应机理的有效手段,但是目前所使用的大多数工况表征技术都是基于(准)稳态的光谱技术,对发生在毫微秒时间尺度的瞬态变化过程很难直接进行观测。本研究通过在时间分辨紫外可见吸收光谱系统中引入电压脉冲,并在时间上同步电脉冲信号与光谱信号,实现了时间分辨率高达3 μs的工况电化学紫外可见吸收光谱测量系统。利用此光谱系统和方法研究了水合铁等电催化剂的水氧化动力学机理,直接揭示了电催化剂表面水氧化中间物种在毫微秒时间尺度的形成、转化和反应动力学。微秒时间分辨的工况电化学紫外可见吸收光谱,可以促进电催化反应动力学机理的研究和认识,指导新型高效电催化剂的设计合成。
Article
Two-Step Sequential Blade-Coating Large-Area FA-Based Perovskite Thin Film via a Controlled PbI2 Microstructure
Yongtao Wen, Jing Li, Xiaofeng Gao, Congcong Tian, Hao Zhu, Guomu Yu, Xiaoli Zhang, Hyesung Park, Fuzhi Huang
2023, 39(2): 2203048-0  doi: 10.3866/PKU.WHXB202203048
[摘要]  (162) [HTML全文] (162) [PDF 2192KB] (162)
摘要:
Solar cells, which are excellent alternatives to traditional fossil fuels, can efficiently convert sunlight into electricity. The intensive development of high-performance photovoltaic materials plays an important role in environmental protection and the utilization of renewable energy. Organic–inorganic hybrid perovskite materials, with a formula of ABX3 (A = methylammonium (MA) or formamidinium (FA); B = Pb or Sn; X = Cl, I, or Br), have exhibited remarkable commercial prospects in high-performance photovoltaic devices owing to their long carrier diffusion length, excellent light absorption properties, high charge carrier mobility, and weak exciton binding energy. Recently, perovskite solar cells, fabricated using halide perovskite materials as light-absorbing layers, have achieved remarkable results; their certified power conversion efficiency has continuously improved and reached 25.7%. However, high-performance devices are usually fabricated using spin-coating methods with active areas below 0.1 cm2. Hence, long-term research goals include achieving a large-scale uniform preparation of high-quality photoactive layers. The current one-step preparation of perovskite films involves the nucleation-crystalline growth process of perovskite. Auxiliary processes, such as using an anti-solvent, are often required to increase the nucleation rate and density of the film, which is not suitable for industrial large-area preparation. Additionally, the large-area preparation of perovskite films by spin-coating will result in different film thicknesses in the center and edge regions of the film due to an uneven centrifugal force. This will cause intense carrier recombination in the thicker area of the film and weak light absorption in the thinner area, which will reduce the performance of the device. To address these problems, the development of a large-area fabrication method for high-performance perovskite light-absorbing layers is essential. In this study, a two-step sequential blade-coating strategy was developed to prepare the FA-based perovskite layer. In general, PbI2 easily forms a dense film; therefore, formamidinium iodide (FAI) cannot deeply penetrate to completely react with PbI2. The PbI2 residue is therefore detrimental to charge transportation. To fabricate the desired porous PbI2 film, tetrahydrothiophene 1-oxide (THTO) was introduced into the PbI2 precursor solution. By forming PbI2·THTO complexes, PbI2 crystallization is controlled, resulting in the formation of vertically packed PbI2 flaky crystals. These crystals provide nanochannels for easy FAI penetration. The 5 cm × 5 cm modules fabricated through this strategy achieved a high efficiency of 18.65% with excellent stability. This indicates that the two-step sequential blade-coating strategy has considerable potential for scaling up the production of perovskite solar cells.
Oxygen Vacancy-Rich Amorphous Copper Oxide Enables Highly Selective Electroreduction of Carbon Dioxide to Ethylene
Tianran Wei, Shusheng Zhang, Qian Liu, Yuan Qiu, Jun Luo, Xijun Liu
2023, 39(2): 2207026-0  doi: 10.3866/PKU.WHXB202207026
[摘要]  (218) [HTML全文] (218) [PDF 2765KB] (218)
摘要:
The ever-increasing carbon dioxide (CO2) emissions caused by excessive fossil fuel consumption induce environmental issues such as global warming. To overcome this, the electrocatalytic CO2 reduction (ECR) under ambient conditions offers an appealing approach for converting CO2 to value-added chemicals and realizing a closed carbon loop. Among the ECR products, ethylene (C2H4), an important building block for plastics and other chemicals, has attracted considerable attention owing to its compatibility with existing infrastructure and the promising substitution of industrial steam cracking. In recent years, numerous efforts have been devoted to developing highly active and selective catalysts for converting CO2 to C2H4, with most studies having focused on Cu-based materials. Despite the significant advancements made to date, the development of the ECR-to-C2H4 process is still hindered by the lack of suitable catalysts that can effectively activate CO2 and strengthen the surface binding of *CO and *COH species. In this study, an amorphous copper oxide (CuOx) nanofilm that is rich in oxygen vacancies was prepared via a facile vacuum evaporation method for the efficient electrocatalytic conversion of CO2 to C2H4. It was expected that the nano-scale electrode thickness would greatly accelerate charge- and mass-transfer during CO2 electrolysis. Moreover, the introduction of oxygen vacancies favored the adsorption of CO2 and intermediates. As a result, in a typical H-cell, the synthesized defective catalyst delivered a maximum Faradaic efficiency of 85 ± 3% at −1.3 V versus the reversible hydrogen electrode and maintained a stable C2H4 selectivity over 48 h in a 0.1 M potassium bicarbonate solution. Interestingly, the performance observed with the synthesized electrocatalyst in this study is comparable with that of state-of-the-art Cu-based ECR catalysts. Additional structural and chemical characterizations confirmed the robust nature of the as-prepared catalyst. Moreover, when the catalyst was utilized in a membrane electrode assembly cell, it achieved a maximum C2H4 partial current density of approximately 115.4 mA∙cm−2 at a cell voltage of −1.95 V and Faradaic efficiency of 78 ± 2% at a cell voltage of −1.75 V. Furthermore, theoretical and experimental analyses revealed that oxygen defects not only favored CO2 adsorption but also enabled strong affinities for *CO and *COH intermediates, which synergistically contributed to a high selectivity for C2H4 formation. We believe that our present work will motivate the exploration of amorphous Cu-based materials for achieving efficient CO2-to-C2H4 electrolysis and be a guide towards fundamentally understanding the mechanism of catalytic CO2 reduction.
Communication
Cobalt-Vanadium Layered Double Hydroxides Nanosheets as High-Performance Electrocatalysts for Urea Oxidation Reaction
Yaoyu Liu, Yuchen Wang, Biying Liu, Mahmoud Amer, Kai Yan
2023, 39(2): 2205028-0  doi: 10.3866/PKU.WHXB202205028
[摘要]  (194) [HTML全文] (194) [PDF 2482KB] (194)
摘要:
Hydrogen is considered as a desirable clean energy source for supporting human life in the future. Electrochemical water splitting is a promising method for generating carbon-free hydrogen. However, the relatively high overpotential of anodic oxygen evolution reaction (OER) is the main obstacle hindering the widespread popularity of water electrocatalysis technology. Recently, urea oxidation reaction (UOR) has gained significant attention as a potential alternative to OER for hydrogen production since the equilibrium potential of UOR is 0.86 V lower than that of OER. Transition metal-based layered double hydroxides (TM-LDHs) have been explored as promising UOR electrocatalysts, with the advantages of diversified metal species, stable two-dimensional layered structure and exchangeability of interlayer anions. To date, most studies have focused on TM-LDHs of late transition metals (e.g., Ni, Co, and Fe). In this work, by combining early and late transition metals, CoV-LDHs nanosheets were fabricated via a simple one-step coprecipitation method as high-performance UOR electrocatalysts. Additionally, cobalt hydroxide (Co(OH)2), with a similar lamellar structure, was synthesized via the same method. When compared with Co(OH)2, CoV-LDHs nanosheets exhibited better UOR performance owing to the following advantages: 1) The nanosheet structure of the as-fabricated CoV-LDHs electrocatalyst exposed a high number of active sites for the electrocatalytic conversion of urea. 2) The introduction of V enhanced the wettability of the CoV-LDHs electrocatalyst; thus, increasing its intrinsic electrocatalytic kinetics. 3) The d-electron compensation effect between Co (3d74s2) and V (3d34s2) was conducive to promoting the adsorption of urea. Therefore, the CoV-LDHs electrocatalyst exhibited a low electrochemical potential (1.52 V vs. the reversible hydrogen electrode, RHE) to achieve a current density of 10 mA∙cm−2 in 1 mol∙L−1 of potassium hydroxide containing 0.33 mol∙L−1 urea, which was 70 mV less than that of Co(OH)2. The Tafel slope value of the CoV-LDHs electrocatalyst (99.9 mV∙dec−1) was lower than that of Co(OH)2 (115.9 mV∙dec−1), indicating faster UOR kinetics over the CoV-LDHs electrocatalyst. Furthermore, the CoV-LDHs electrocatalyst displayed high stability, with a negligible potential increase after a 10-h chronopotentiometry test by maintaining the current density of 10 mA∙cm−2. In conclusion, the present work not only shows that the d-electron compensation effect between early and late transition metals could adjust the local electronic structure of TM-LDHs to improve the UOR efficiency, but also provides a feasible route to design dedicated nanostructured TM-LDHs as high-performance UOR electrocatalysts.
综述
电解液调控策略提升水系锌离子电池正极材料电化学性能
齐亚娥, 夏永姚
2023, 39(2): 2205045-0  doi: 10.3866/PKU.WHXB202205045
[摘要]  (211) [HTML全文] (211) [PDF 6695KB] (211)
摘要:
水系锌离子电池(ZIBs)因安全性高、成本低、环境友好,以及负极锌高的理论容量(820 mAh∙g−1)和低的氧化还原电位(−0.76 V vs. SHE)等优点而受到研究者们的广泛关注,有望应用于大规模储能领域,但循环寿命仍是限制其规模化应用的瓶颈之一。通过电解液优化调控策略,可有效抑制正极材料的溶解、结构坍塌和界面副反应等问题,从而提高水系ZIBs的电化学性能。本文综述了电解液调控策略提升水系ZIBs正极材料电化学性能的研究进展,讨论了该策略所解决的具体问题和局限性,并对电解液体系的发展方向进行了展望。
镁离子电池正极材料研究进展
张默淳, 冯硕, 邬赟羚, 李彦光
2023, 39(2): 2205050-0  doi: 10.3866/PKU.WHXB202205050
[摘要]  (169) [HTML全文] (169) [PDF 3047KB] (169)
摘要:
镁离子电池(MIBs)因镁资源储量丰富、体积能量密度大、金属镁空气中相对稳定等优势,被认为是具有大规模储能应用潜力的电池体系。然而,镁离子较高的电荷密度和较强的溶剂化作用导致其在正极材料中的可逆脱嵌和固-液界面上的离子扩散相当缓慢,严重影响了MIBs的电化学性能。近年来,人们针对MIBs正极材料开展了大量工作,取得了一定进展,但是还存在不少问题。本文先从MIBs体系的特点出发,阐述其优势和目前所面临的主要挑战,然后从无机正极材料和有机正极材料两方面展开,梳理并总结了各类正极材料的局限性及其解决策略,对优化方法和材料性能间的相关性进行归纳和讨论,为今后进一步发展具有优异电化学性能的MIBs正极材料提供可能的参考。
“绿氢”工业化碱性催化剂研究现状及未来展望
徐斯然, 吴奇, 卢帮安, 唐堂, 张佳楠, 胡劲松
2023, 39(2): 2209001-0  doi: 10.3866/PKU.WHXB202209001
[摘要]  (168) [HTML全文] (168) [PDF 6471KB] (168)
摘要:
电解水制氢技术的发展对于加快实现全球碳中和目标具有重要意义。然而,碱性介质中缓慢的析氢/析氧反应动力学过程目前是阻碍该技术发展的瓶颈问题。基于此,本文首先综述了碱性环境下析氢反应与析氧反应不同的动力学理论机制,总结了针对改善动力学反应过程的理论设计策略。随后,介绍了目前电解水催化剂的设计理念及方向。对新兴的“绿氢”技术而言,探索在高电流密度下高性能电催化剂对这项技术在工业化应用推广中起着核心作用。同时,大规模合成策略是辅助合成工业电极的关键技术。进一步,我们在推进“绿氢”工业化应用的基础上总结了目前常用三种电解槽,介绍了目前电解槽设计的局限性及对应解决方案。总之,深入研究适用于碱性环境中的工业电催化剂、商业膜或电解槽的设计,提高对工业设计原则的理解,对于获得效率更高、安全性更高、实用性更强的工业电解槽具有重要意义。

编委会

发布时间:


《物理化学学报》第4届编委会

(按拼音排序)

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

联系我们

发布时间: 2018-05-02


编辑部工作人员联系方式
 

张小娟
主任
010-62756388
黄路
编辑
010-62751724
欧阳贱华
编辑
010-62751721
於秀芝
编辑
010-62751724
熊英
编辑
010-62751724
周虹
技术编辑
010-62751724

 

通讯地址:北京市北京大学化学学院物理化学学报编辑部

邮政编码:100871

 

发布日期:2009-06-24 浏览: