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1.
作为铝离子电池(AIBs)的正极材料,过渡金属硫族化合物(MX2 (X=S、Se、Te))具有理论比容量较高和电负性较低等优点,在铝离子电池应用领域极具发展前景。本文以提高过渡金属硫族化合物的储铝性能为目的,综述了过渡金属硫族化合物(MX2 (X=S、Se、Te))的储铝机理及其电化学性能的关系,并针对目前过渡金属硫族化合物存在的问题,总结研究者们提出的相应解决方案并归纳此类材料的主要改性技术手段。最后,对过渡金属硫族化合物正极材料的发展方向进行展望,并探讨改善其整体电化学性能的可行策略。  相似文献   

2.
赵东江  尹鸽平魏杰 《化学进展》2009,21(12):2753-2759
简要介绍了聚合物膜燃料电池(PEMFC)的特点及其存在的主要技术问题。综述了PEMFC阴极非Pt催化剂的研究进展,重点讨论了过渡金属硫族化合物、过渡金属合金、过渡金属氮化物、过渡金属氧化物以及过渡金属大环化合物等非Pt催化剂对氧还原反应(ORR)的催化活性、化学或电化学稳定性以及耐甲醇能力等性能,提出了阴极非Pt催化剂存在的问题以及发展趋势。Ru基硫族化合物、Pd基合金和过渡金属大环化合物催化剂具有良好的性能,有望成为PEMFC阴极Pt基催化剂的替代材料。  相似文献   

3.
金属-有机框架化合物(以下简称金属-有机框架)是一类有机配体与金属中心通过自组装形成的具有三维框架结构的多孔材料,其特异复杂的结构使其具有良好的化学性能。金属-有机框架化合物在分析化学方面的应用受到广泛关注,在电化学传感器应用方面也取得了显著进展。本文简要介绍近年来金属-有机框架用于构建电化学传感器的方法及在电化学传感器中的作用;对基于金属-有机框架的电化学传感器的应用进行了综述;分析了目前金属-有机框架-电化学传感器研究中存在的问题和局限性并对其应用进行了展望。  相似文献   

4.
硫醚基团广泛存在于天然产物和药物中,独特的分子结构使其具有较高的生物活性,常被用于药物、电化学材料和香料香精的合成。过渡金属催化的C-S键偶联反应因具有操作简单、高效廉价、反应条件温和等优点而成为合成硫醚化合物的主要方法之一。本文重点从有机硫源和无机硫源两方面,对近年来过渡金属催化合成硫醚的研究进行了综述。  相似文献   

5.
近年来,过渡金属催化反应已经成为有机化学中构建碳碳键和碳杂原子键的最有效方法之一,并引起了化学家的极大研究兴趣.杯芳烃是继冠醚和环糊精之后的第三代超分子主体化合物,其配位性能一直是超分子化学研究的热点.通过对其下缘的酚羟基、上缘的苯环对位以及连接苯环单元的亚甲基进行设计改造,杯芳烃可以有效地作为过渡金属催化剂的配体,或者与过渡金属正离子组装成为新的过渡金属催化剂,从而高效地促进反应的进行.主要介绍了近十年来,杯芳烃作为不同过渡金属催化剂的配体并用于各种过渡金属催化反应的研究进展.  相似文献   

6.
过渡金属大环配合物(例如酞菁和卟啉)对氧的电化学还原具有很高的催化活性,因而是目前电化学最活跃的研究领域之一.关于氧在过渡金属大环配合物上电化学还原机理,一般认为与过渡金属的价态变化有关.近年来,由于稀土双酞菁具有电致变色(electrochromic)的特性,引起了人们极大的兴趣,并对它们的电化学行为进行了一系列的研究,但关于它们对氧的电化学还原作用却未见报道.我们利用循环伏安法研究了某些稀土单酞菁和双酞菁对氧的电化学还原的影响,并提出了氧的电化学还原的反应历程.  相似文献   

7.
含硫四氮杂卟啉过渡金属配合物具有比金属卟啉、金属酞菁更为优异的光电功能和催化特性,故近十多年来颇受重视。我们对该类金属配合物和自由配体的合成、性质及其光-光、光-电转换,电化学、光电化学催化,光敏和气敏等功能正进行深入的研究。本文简要报道标题化合物的合成、表征和电子吸收光谱、发射光谱及顺磁共振波谱。  相似文献   

8.
过渡金属催化导向碳氢键活化与不饱和分子的环化反应已成为合成复杂碳环和杂环化合物的高效途径,但反应中往往需要额外加入化学计量化学氧化剂来实现反应循环.电化学有机合成可利用电流代替昂贵、有毒的化学氧化剂,是一种环境友好的绿色合成手段.近年来,电化学有机合成与过渡金属(如Pd、Ni、Co、Ru、Cu、Rh、Ir等)催化碳氢键活化的结合取得了显著的进展.重点介绍了过渡金属催化导向C—H活化与炔烃、烯烃、一氧化碳和异氰等不饱和分子的电氧化环化反应的最新进展,并对该领域未来发展方向进行了展望.  相似文献   

9.
超级电容器因其在电动车和便携式设备上巨大的应用潜力而受到广泛关注. 电极材料是超级电容器的关键组成部分, 决定了超级电容器性能的好坏. 近来大量研究以碳材料和过渡金属化合物作为电极材料. 然而, 碳材料电容值极小与过渡金属化合物导电性和稳定性差, 极大地限制了它们在超级电容器中的应用. 本综述重点介绍了我们课题组近年来在设计、可控制备及优化碳材料与过渡金属氧/氮化物电容性能的相关研究工作, 并讨论了材料构效关系及其调控机理. 最后对碳材料和过渡金属化合物作为电极材料的日后研究进行了展望.  相似文献   

10.
作为析氢反应的电催化剂,富金属的过渡金属硫化物因能克服富硫金属催化剂所存在的如导电性有限和缺乏必要的纳米结构等不足,近年来受到越来越多的关注.本文介绍了具有镍黄铁矿型结构的三元富金属硫化物复合材料FexCo9-xS8和NiyCo9-yS8(x=y=0-4.5)的合成、表征及其电催化研究.首先,研究了二元钴化合物Co9S8中Co逐步被Fe或Ni取代直至4.5当量的变化过程.硫镍铁矿复合物中组分的变化有助于不同温度下酸性介质中的质子还原.其次,在还原电催化条件下,复合物中元素化学计量变化对其电化学活化/失活行为有决定性的影响.与Co9S8相比,Co缺陷复合材料表现出了更高的HER性能.Ni/Co化合物通常表现出比类似结构Fe/Co化合物更高的电催化析氢活性.  相似文献   

11.
近年来, 过渡金属硫族化合物(TMDs)作为一种新兴的二维材料, 因其独特的层状结构及电学特性成为超级电容器电极材料的理想候选者之一. 本文介绍了二维TMDs的常用合成方法, 阐述了钼基、 钨基和钒基等TMDs在超级电容器中的研究进展, 分析了形貌、 尺寸和改性方法等因素对TMDs材料电化学性能的影响, 并对TMDs在超级电容器领域的工业化应用和挑战进行了总结与展望.  相似文献   

12.
超级电容器作为一种新型的能源存储装置,因为其比容量大、充放电速度快、循环寿命长等优点,在储能领域引起了极为广泛的关注。电极材料是决定超级电容器性能的核心因素,其中,常用的超级电容器电极材料主要有如下三类:碳基材料、金属氧化物及氢氧化物材料和导电聚合物材料。本文综述了超级电容器的工作原理并详细介绍了基于碳材料及其二元、三元复合体系的电极材料的研究进展。  相似文献   

13.
With the ever‐increasing depletion of nonrenewable fossil fuel reserve, greater attention has been directed towards renewable energy storage devices. One of the most important of such devices is the supercapacitor, which exhibits high specific capacitance. Polyaniline (PAni) is a versatile conducting polymer, which has demonstrated excellent electrochemical properties along with good stability and ease of synthesis. Therefore, PAni has been extensively used in the fabrication of supercapacitors. In the last few decades, researchers have studied the effect of morphology, developed during the synthesis of PAni, on its electrochemical properties. It is known that the electrical conductivity and the electrochemical properties of PAni get influenced by the level and type of dopant used, the method of synthesis adopted, and the surface area and porosity possessed. However, it has been realized that supercapacitors based on PAni suffer from short cycle life. This led to development of PAni composites with carbon‐based materials and transition metal oxides. In this review, focus has been laid on the achieved performance levels of the recently developed PAni‐based supercapacitors. In addition, an attempt has been made to study the fundamental aspects of the conductivity and the electrochemical properties of PAni and their effect on the supercapacitor performance. Moreover, several new interesting applications of PAni‐based supercapacitors have also been included in this review.  相似文献   

14.
Graphene composites with metal or metal oxide nanoparticles have been extensively investigated owing to their potential applications in the fields of fuel cells, batteries, sensing, solar cells, and catalysis. Among them, much research has focused on supercapacitor applications and have come close to realization. Composites include monometal oxides of cobalt, nickel, manganese, and iron, as well as their binary and ternary oxides. In addition, their morphological control and hybrid systems of carbon nanotubes have also been investigated. This review presents the current trends in research on metal oxide/graphene composites for supercapacitors. Furthermore, methods are suggested to improve the properties of electrochemical capacitor electrodes.  相似文献   

15.
《印度化学会志》2023,100(1):100817
Supercapacitors are high energy density and power density materials in the electronics industry. Noble metals and their composites have been the most successfully applied in supercapacitors. This review is focused on noble metal-based materials that have been used to improve electrochemical supercapacitors over the last decade. This review describes the role of various noble metals, binary composites with transition metals, binary composites with carbon-based materials, and ternary composites containing both transition metals and carbon-based materials as supercapacitor electrode materials. The effects of the electrode material, growth tactics, structure, size and morphology of the nanostructured materials on device performance are discussed.  相似文献   

16.
With the increased energy demand,developing renewable and clean energy technologies becomes more and more significant to mitigate climate warming and alleviate the environmental pollution.The key point is design and synthesis of low cost and efficient materials for a wide variety of electrochemical reactions.Over the past ten years,two-dimensional(2D)nanomaterials that graphene represents have been paid much attention as a class of the most promising candidates for heterogeneous electrocatalysts in electrochemical storage and conversion.Their unique properties,such as good chemical stability,good flexibility,and good electronic properties,along with their nanosized thickness and large specific area,make them exhibit comprehensively good performances for energy storage and conversion.Here,we present an overview on the recent advances in electrochemical applications of graphene,graphdiyne,transition metal dichalcogenides(TMDs),and MXenes for supercapacitors(SCs),oxygen reduction reaction(ORR),and hydrogen evolution reaction(HER).  相似文献   

17.
《中国化学快报》2020,31(9):2177-2188
In the past few years, the increasing energy consumption of traditional fossil fuels has posed a huge threat to human health. It is very imperious to develop the sustainable and renewable energy storage and conversion devices with low cost and environment friendly features. Hybrid supercapacitors are emerging as one of the promising energy devices with high power density, fast charge-discharge process and excellent cycle stability. However, morphology and structure of the electrode materials exert serious effect on their electrochemical performances. In this review, we summarized recent progresses in transition metal oxide based electrode materials for supercapacitors. Different synthesis routes and electrochemical performances of electrode materials and storage mechanisms of supercapacitor devices have been presented in details. The future developing trends of supercapacitor based on metal oxide electrode materials are also proposed.  相似文献   

18.
对高性能超级电容器不断增长的需求促进了无粘合剂电极材料的快速发展。静电纺纳米纤维由于具有良好的柔性、大比表面积、高孔隙率、容易制备等优点引起了研究者们的强烈关注。本文综述了静电纺纳米纤维基无粘合剂电极材料在超级电容器领域的研究进展,阐述了不同材料的设计制备过程和提升电化学性能的诸多方法,并指明了静电纺纳米纤维基超级电容器无粘合剂电极材料的发展机遇与挑战,为性能优异的无粘合剂超级电容器电极材料的进一步开发与应用拓宽了思路。  相似文献   

19.
胶体离子超级电容器的比容量评价   总被引:1,自引:1,他引:0  
胶体离子超级电容器作为一种新型的超级电容器,其同时具有能量密度和功率密度高的独特优势。 目前已经发展了包括多种过渡金属阳离子和稀土阳离子,例如Mn2+、Fe2+、Co2+、Ni2+、Cu2+、Sn2+、Sn4+、La3+、Ce3+、Er3+和Yb3+的胶体离子超级电容器体系。 在电化学反应中,识别出电活性物质的存在形式对研究电极反应机理和提高比容量具有重要价值。 本文主要通过对电活性物质比容量的探讨,理解这种新型胶体离子超级电容器的电化学储能机理。 评述了胶体离子超级电容器的比容量核算方式,提出了以阳离子为标准核算比容量的原因,并与传统超级电容器的核算方式进行了比较,表明胶体离子超级电容器在提高能量密度方面具有潜在优势,有望突破现有电化学储能设备的技术瓶颈,实现下一代高能量储能器件的开发。  相似文献   

20.
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.  相似文献   

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