基于四硫富瓦烯的无金属共价有机框架材料用于高效电催化析氧反应

共价有机框架(COFs)在电催化析氧反应(OER)中的应用得到了广泛的关注。然而,大多数无金属共价有机框架(COFs)的导电性较差,不利于OER反应。四硫富瓦烯(TTF)是一种良好的电子供体,具有快速的电子转移能力,将TTF整合到共价有机框架骨架中将有助于电子的转移。在此,我们报道了一种基于四硫富瓦烯的二维无金属共价有机框架材料,JUC-630。与不含四硫富瓦烯的同类材料(Etta-Td COF)相比,JUC-630具有较低的过电位(400 mV)和塔菲尔斜率(104 mV∙dec⁻¹)。本研究提出了合理设计功能基元的策略,这有助于大大提高COF材料的OER催化活性。     

基于醌基的共价有机框架用于电催化析氧反应

将蒽醌作为构筑单元设计合成了醌基功能化的新型2,6-二氨基蒽醌共价有机框架(DAAQ-COF). 粉末X射线衍射、 氮气吸附-脱附、 红外和热重等分析结果表明, DAAQ-COF具有高的结晶度和比表面积(577 m²/g). 此外, 醌基功能化的无金属DAAQ-COF显示出高的析氧反应(OER)活性(10 mA/cm²下, 过电位389 mV, Tafel斜率135 mV/dec). 这源于引入的醌基基团有效改变了COF框架的电子结构和化学特性, 加上COF材料本身的高结晶度和比表面积, 使得反应物能更有效地与活性位点接触, 从而促进OER进程. 这些结果表明合理地设计功能化的COF材料能够进一步推动此类材料在电催化领域的应用.     

过渡金属碳氮化物在电催化领域的应用:改性和杂化（英文）

化石能源过度消耗导致的环境污染问题使发展绿色可持续替代能源成为人们需要面对的重要问题.寻找绿色高效的方法生产可再生燃料是一个有效的策略,在减少二氧化碳排放的同时可满足能源需求.电催化是一种实现清洁能源的重要途径,可将地球上含量丰富的H₂O, N₂, CO₂和O₂等转化为燃料和化合物.尽管贵金属Pt, RuO₂等具有优异的电催化性能,但由于成本高、储量少限制了其大规模应用,因此开发一种高活性且低成本的电催化剂是实现大规模应用的关键.由于具有独特的形貌和电子结构,石墨烯,黑磷和二硫化钼等二维材料已经在电催化领域得到了广泛应用.作为一种新型的二维材料,碳化物、氮化物和碳氮化物(MXenes)不仅具有良好的机械性能和大比表面积,其较好的导电性和基底面上丰富的活性位点在促进可持续能源发展方面发挥了更重要的作用.自MXenes首次被用于析氢反应(HER)以来,大量的工作预测并合成了具有多种元素的MXenes及其复合材料,并用于电催化反应.本文从理论和实验两方面综述了基于MXenes在HER...     

Pt单原子催化剂的构建和应用

不同于纳米和亚纳米催化,单原子催化在负载极低金属含量的同时能极大地提高金属原子的利用率,具有更优越的催化性能。单原子催化剂（SACs）是一种特殊的负载型金属催化剂,指载体上的所有金属组分都以单原子分散的形式存在。当催化剂的尺寸是单原子级别时,其原子利用率达到了百分百,此时其能级结构、电子结构会发生根本性变化,表面自由能急剧增大,催化活性随之增加;但孤立的金属单原子容易聚集导致催化活性下降,因此能锚定单原子的载体尤为重要。载体既可以起到固定单原子的作用,又可以协同单原子提高反应催化活性,是催化领域的研究前沿。本文基于Pt单原子催化剂具有贵金属用量少、活性高、稳定性好、金属-载体相互作用强等优点,介绍了Pt单原子的几种载体,包括氧化物材料,有机金属框架（MOF）材料,碳基材料以及其他材料。对Pt单原子的表征方法以及Pt单原子催化剂在电催化析氢反应（HER）,氧还原反应（ORR）,CO氧化及其他方面的应用进行了概述,对Pt单原子材料的发展趋势进行了展望。     

多壳层中空镍钴双金属磷化物纳米球用于高效电催化析氧北大核心CSCD

析氧反应是金属-空气电池和电解水制氢等电化学系统中关键的反应,研究其高效稳定非贵金属电催化剂至关重要。本文以金属有机骨架化合物(MOF)作为前驱体,通过高温煅烧制备了具有多壳层中空结构的镍钴双金属磷化物(NiCo-P)。这种独特的结构有利于电解液的渗透,能够提供丰富的暴露活性位点和快速传质路径,同时,镍钴双金属具有协同作用促进电化学性能。结果表明,n(Ni)∶n(Co)=1∶10制备的NiCo-P-0.1催化剂在1.0 mol/L KOH电解液中表现出良好的催化活性和稳定性,在10 mA/cm^(2)电流密度的过电势为329 mV,具有良好的应用前景。本工作为高活性和高稳定性的电催化析氧催化剂的制备提供了一种全新途径。     

调控碳材料的功函数以大幅度提升其电催化氧还原性能

氧的电催化还原反应是燃料电池装置与金属空气电池的阴极反应, 具有重大的研究意义. 在众多的非铂催化剂中,碳材料因其低廉的价格以及独特的物理化学性质受到了广泛的关注. 自从发现氮掺杂的碳纳米阵列具有优异的氧还原活性后, 不同类型的氮掺杂的碳也得到了深入研究. 例如近年来兴起的由金属有机框架衍生的氮掺杂的碳材料, 兼具丰富...     

金属有机框架材料在质子交换膜燃料电池中的潜在应用

金属有机框架亦称作多孔配位网状结构,是一种多孔晶态材料,具有结构可设计、孔壁可功能化修饰、高度晶态化、比表面积大及优良的导电性等诸多优点,使其在能源转换及储存方面备受关注。本文详细介绍了新型金属有机框架质子导体及电催化剂在燃料电池方面的相关研究;综述了国内外近年来在金属有机框架质子交换膜和氧还原电催化领域所取得的一些重要进展,例如金属有机框架质子交换膜电导率可高达1.82 S·cm^-1（70℃,90% RH）,金属有机框架电催化剂作为阴极在膜电极测试中可产生0.91 W·cm^-2（0.6 V）的峰值功率密度;并指出了金属有机框架在质子交换膜和电催化剂研究中存在的问题,这为今后开发高电导性质子交换膜和高催化活性电催化提供了新思路。     

过渡金属硫化物相关电催化剂的设计与应用研究（英文）

自从国际社会提出“碳达峰、碳中和”目标以来,人们越来越意识到节约资源、保护环境、开发新能源的必要性.氢能(H₂)作为最具竞争力的清洁能源之一,引起了研究人员的广泛关注.电化学全解水被认为是一种利用风能和太阳能产生氢气的有效技术,其主要由两个半反应组成:析氧反应(OER)和析氢反应(HER).然而,在实际工业化生产过程中阳极反应动力学OER慢,能量转换效率低,阴极反应稳定性差,导致经济效益不理想,因此,急需开发和探索耐久高效的电催化剂.过渡金属硫化物因具有独特的结构特征、丰富的活性位点和可调控的电子性质和组成,而被广泛用于电化学全解水制氢.本文综述了过渡金属硫化物的合成方法,一般包括:水热(溶剂热)法、电化学沉积法、液相剥离法、化学气相沉积法和球磨法,并概述了不同方法的基本概念、合成步骤以及优缺点.总结了近年用于电催化领域中典型单一硫化物(包括MoS₂,WS₂,Co₃S₄,Ni₃S₂等)材料的合成方法和机理,明确了S元素在整个电催化过程...     

用尖晶石型化合物NiCo2O4和复合镀技术制备析氧电极

为减少析氧电位、提高电极的稳定性、降低能耗和成本，人们一直在努力合成各种过渡金属复合氧化物作为析氧的电催化材料［１］．研究表明，尖晶石型化合物ＮｉＣｏ２Ｏ４对氧的析出有较高的催化活性［２］．但因其制备方法多为喷涂热解法，需４００℃以上温度，因此易发生...     

双金属磷化物和杂原子共修饰碳材料的制备及电催化性能

以高含氮量的苯胺五聚体二羧酸为配体,在预氧化的泡沫镍上通过溶剂热反应合成了Fe,Co金属有机框架材料Fe/Co-MOF,再以Fe/Co-MOF为金属源和碳源,经磷化后制备出一种新型的双金属(Fe,Co)和杂原子(N,P)共掺杂的碳材料Fe/Co/P-NPs.通过扫描电子显微镜和高分辨透射电子显微镜表征发现,Fe/Co/P-NPs由纳米粒子和纳米片组成,并且形成Fe₂P和Co₂P两种晶体.电化学测试结果表明,Fe/Co/P-NPs在析氢、析氧及水电解中表现出了优异的多功能催化活性.在1 mol/L KOH中,Fe/Co/P-NPs在10和100m A/cm²电流密度时的析氧过电位分别为270和300 m V,均小于其它对比材料,优于负载在泡沫镍上的RuO₂.作为水电解双功能催化剂,Fe/Co/P-NPs仅需1. 48 V的电位即可获得10 m A/cm²的电流密度.     

导电金属有机框架材料在电催化中的成就，挑战和机遇

To fulfill the demands of green and sustainable energy, the production of novel catalysts for different energy conversion processes is critical. Owing to the intriguing advantages of the intrinsic active species, tunable crystal structure, remarkable chemical and physical properties, and good stability, metal-organic frameworks (MOFs) have been extensively investigated in various electrochemical energy conversions, such as the CO₂ reduction reaction, N₂ reduction reaction, oxygen evolution reaction, hydrogen evolution reaction, and oxygen reduction reaction. More importantly, it is feasible to change the chemical environments, pore sizes, and porosity of MOFs, which will theoretically facilitate the diffusion of reactants across the open porous networks, thereby improving the electrocatalytic performance. However, owing to the high energy barriers of charge transfer and limited free charge carriers, most MOFs show poor electrical conductivity, thus limiting their diverse applications. As reported previously, MOFs were used as a porous substrate to confine the growth of nanoparticles or co-doped electrocatalysts after annealing. The conductive MOFs can combine the advantages of conventional MOFs with electronic conductivity, which significantly enhance the electrocatalytic performance. In addition, conductive MOFs can achieve conductivity via electronic or ionic routes without post-annealing treatment, thereby extending their potential applications. Different synthesis strategies have recently been developed to endow MOFs with electrical conductivity, such as post-synthesis modification, guest molecule introduction, and composite formatting. The performance of conductive MOFs can even outperform those of commercial RuO₂ catalysts or Pt-group catalysts. However, it is difficult to endow most MOFs with high conductivity. This review summarizes the mechanisms of constructing conductive MOFs, such as redox hopping, through-bond pathways, through-space pathways, extended conjugation, and guest-promoted transport. Synthetic methods, including hydro/solvothermal synthesis and interface-assisted synthesis, are introduced. Recent advances in the use of conductive MOFs as heterogeneous catalysts in electrocatalysis have been comprehensively elucidated. It has been reported that conductive MOFs can demonstrate considerable catalytic activity, selectivity, and stability in different electrochemical reactions, revealing the immense potential for future displacement of Pt-group catalysts. Finally, the challenges and opportunities of conductive MOFs in electrocatalysis are discussed. Based on systematic synthesis strategies, more conductive MOFs can be constructed for electrocatalytic reactions. In addition, the morphology and structure of conductive MOFs, which can change the electrochemical accessibility between substrates and MOFs, are also crucial for catalysis, and thus, they should be extensively studied in the future. It is believed that a breakthrough for high-performance conductive MOF-based electrocatalysts could be achieved.     

高效氧催化反应中的金属有机骨架材料（英文）

氧电催化反应包括氧气还原反应(ORR)和氧气析出反应(OER).作为核心电极反应,这两个反应对诸多能源存储与转换技术(比如燃料电池、金属空气电池以及全水分解制氢等)的能量效率起决定性作用.然而,ORR和OER涉及多个反应步骤、多个电子转移过程以及多相界面传质过程.这些复杂的过程较大程度上限制了ORR和OER的反应速率.从理论和实践两个方面来看,ORR和OER都需要高效电催化剂的参与来促进其反应速率,从而能够最终提高上述能源存储与转换技术的能量转换或利用效率.目前,以Pt,Pd,Ir,Ru为代表的贵金属基电催化剂具有十分突出的电催化性能.但是,过高的成本和过低的储量始终制约着贵金属基电催化剂在催化ORR和OER反应方面,乃至在能源存储与转换技术领域的规模化应用.因而,开发高效非贵金属基氧电催化剂成为近年来能源存储与转换领域的研究重点之一.在众多已经报道的非贵金属基氧电催化剂中,金属有机骨架材料(MOFs)备受瞩目.MOFs是一类由有机配体和金属节点通过配位键自组装而成的晶态多孔材料.它们具备超高比表面积、超高孔隙率以及规则性纳米孔道.相比较其他传统的多孔材料(比如活性炭、分子筛、介孔炭、介孔氧化硅等),MOFs最主要的优势在于它们的结构和功能可以依据需求通过选择合适的有机配体和金属节点进行便利地设计,或通过后处理进行必要的改性和调节.基于独特的多孔特性以及结构与功能的可设计、可调节性,MOFs在气体分离与存储、异相催化、化学传感、药物输送、环境保护以及能源存储与转化等领域都具有潜在的应用价值.因而,近年来,MOFs备受基础研究领域和工业界的青睐.针对MOFs开展的基础研究和应用开发逐渐成为诸多领域的研究焦点.也正由于MOFs具有的上述优异特性,尤其是结构与功能的可设计、可调节性,使得设计制备基于单纯MOFs以及MOFs衍生材料成为开发高效非贵金属基氧电催化剂的新途径.本综述首先论述了基于单纯MOFs的氧电催化剂(包括纯MOFs、活性物种修饰的MOFs以及与导电材料构成的复合MOFs)的合成以及它们在ORR或OER催化反应中应用的研究进展.在第二部分论述中,本综述主要针对MOFs衍生的各类氧电催化剂(包括无机微米-纳米结构/多孔碳复合材料、纯多孔碳材料、纯无机微米-纳米结构材料以及单原子型电催化材料)的研究进展进行了简要介绍和讨论.最后,本综述对MOFs基氧电催化剂目前存在的挑战进行了简要分析;同时,也对这类氧电催化剂的通用设计准则以及未来发展方向进行了展望.尽管存在诸多挑战,MOFs始终被认为是极好的"平台"材料.充分利用它们将有利于开发高效且实用的非贵金属基氧电催化剂.     

Two-dimensional Metal-Organic Frameworks as Electrocatalysts for Oxygen Evolution Reaction

Oxygen evolution reaction(OER) plays an important role in many electrochemical systems. However, its sluggish kinetics severely limits the development of next-generation energy technologies. Recently, two-dimensional(2D) metal-organic frameworks(MOFs) have attracted much attention as a class of promising electrocatalysts. Their diverse components and tunable structures provide a new platform to design and explore ideal electrocatalysts. The ultrathin characteristics including high specific surface area, abundant exposed metal sites and fast electronic transfer further promote the electrocatalytic performance of 2D MOFs. Therefore, many attempts have been made in synthesizing 2D MOF-based electrocatalysts in recent years. This review focuses on the strategies to fabricate 2D MOFs with high electrocatalytic performances for OER. The discussion on challenge and development of their electrocatalytic application is also presented.     

Progress of transition metal chalcogenides as efficient electrocatalysts for energy conversion

The continuous excessive usage of fossil fuels has resulted in its fast depletion, leading to an escalating energy crisis as well as several environmental issues leading to increased research towards sustainable energy conversion. Electrocatalysts play crucial role in the development of numerous novel energy conversion devices, including fuel cells and solar fuel generators. In particular, high-efficiency and cost-effective catalysts are required for large-scale implementation of these new devices. Over the last few years, transition metal chalcogenides have emerged as highly efficient electrocatalysts for several electrochemical devices such as water splitting, carbon dioxide electroreduction, and, solar energy converters. These transition metal chalcogenides exhibit high electrochemical tunability, abundant active sites, and superior electrical conductivity. Hence, they have been actively explored for various electrocatalytic activities. Herein, we have provided comprehensive review of transition-metal chalcogenide electrocatalysts for hydrogen evolution, oxygen evolution, and carbon dioxide reduction and illustrated structure–property correlation that increases their catalytic activity.     

石墨烯基催化剂的设计合成与电催化应用

为了解决能源匮乏和环境污染的问题,研究人员正致力于寻找清洁可持续的新能源。 其中,氧气还原、氧气析出、析氢反应等是紧密联系新型清洁能源获取和存贮的重要电化学反应。 为了提高其能量转化效率,电催化剂(如碳载铂Pt/C)被广泛地用于降低其反应活化能、提高能量转化效率。 近年来,石墨烯作为一种具有高比表面积和优异导电性的二维碳材料受到了广泛关注。 通过表面杂原子掺杂、缺陷调控和引入催化活性组分等方式,获得了催化性能与贵金属催化剂相媲美,且低价格和高稳定性的非贵金属石墨烯基催化材料。 针对氧气还原、氧气析出和析氢反应在燃料电池、金属-空气电池和电催化水分解中的应用,本文概括综述了通过表/界面结构性质调控提高石墨烯电催化性能和稳定性,获得具有双功能或复合催化性能的石墨烯基催化剂的最新研究进展。 最后总结和展望了亟待解决的问题及未来的发展趋势。     

Recent advances of layered double hydroxides–based bifunctional electrocatalysts for ORR and OER

The oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) have attracted increasing attention for the sake of clean, renewable, and efficient energy technologies in recent years. The design of ORR/OER bifunctional electrocatalysts is a challenging task in the promotion of highly efficient rechargeable metal-air batteries as well as regenerative fuel cells. Owing to the wide adaptability of different types and ratios of metals in the interlayer space as well as the adjustable interlayer distance, composite materials with layered double hydroxides (LDHs) and their derivatives have recently been registered as electrode materials and catalysts supports for various electrochemical reactions. This study examines the recent development of bifunctional electrocatalysts based on LDHs for ORR/OER to expand the application of LDHs in the field of energy storage and conversion. Various bifunctional electrocatalysts associated with LDHs are discussed in detail to improve their performance. Finally, existing problems and future prospects for improving the performance of LDHs bifunctional electrocatalysts are proposed.     

Recent advances in energy chemistry of precious-metal-free catalysts for oxygen electrocatalysis

The rational design and effective construction of precious-metal-free materials for OER and ORR, respectively, are reviewed in the respects of electronic structure regulation, nanostructure tailor, and freestanding electrode fabrication. This affords fresh concepts for oxygen electrocatalysis and is also enlightening for other energy catalysis with targeted optimization.     

层状双金属氢氧化物/石墨烯复合材料及其在电化学能量存储与转换中的应用

高效的电化学能量存储与转换功能材料及其器件近年来受到了人们的广泛关注。层状双金属氢氧化物/石墨烯（LDH/G）复合物就是一类重要的能源材料。它们兼具LDH和石墨烯的优异的物理、化学性能,同时克服了LDH导电性差和石墨烯片易于团聚的问题;在超级电容器和电化学催化分解水等方面具有广泛应用。本文综述了LDH与化学修饰石墨烯（氧化石墨烯,还原氧化石墨烯及其衍生物）的有效复合的方法及其在电化学能量存储与转换领域中的应用,特别是关于基于该类材料的超级电容器及电化学析氧反应催化的研究;对LDH/G复合材料研究领域中的挑战和未来发展方向做了展望。     

金属-空气电池中双功能电催化剂微纳结构设计（英文）

金属-空气二次电池在可再生电能的存储和转换方面具有广阔的应用前景.在金属-空气二次电池的空气侧,放电时发生氧还原反应(ORR),充电时发生氧析出反应(OER).然而, ORR和OER反应的动力学过程缓慢,因此限制了金属-空气二次电池的实际应用.因此,发展高性能ORR和OER电催化剂对金属-空气二次电池的发展尤为重要.目前,大多数的研究集中在ORR或OER的单功能电催化剂上,而关于双功能电催化剂的研究和综述相对较少.两个反应均具有较高的过电位和较缓慢的动力学过程,而且充电过程的高电压会导致ORR催化剂失活,反之亦然.因此,开发针对这两个反应均具有高活性和高稳定性的双功能电催化剂极具挑战性.近年来,研究者对具有低成本和高性能双功能电催化剂进行了探索.这些双功能电催化剂包括碳基材料,过渡金属材料和复合材料.双功能电催化剂可以通过提高本征活性和表观活性两种策略来提高其整体的活性.其中,本征活性与晶体结构和电子结构密切相关,即可以通过调节晶体结构和电子结构来提高其本征活性.例如,可以改变金属-氧键的强度、氧空位浓度等来调变电催化活性.在碳基材料中掺杂杂原子可以改变碳的电荷密度分布,从而实现对电催...     

An Overview of Metal-Organic Framework Based Electrocatalysts: Design and Synthesis for Electrochemical Hydrogen Evolution,Oxygen Evolution,and Carbon Dioxide Reduction Reactions

Due to the increasing global energy demands, scarce fossil fuel supplies, and environmental issues, the pursued goals of energy technologies are being sustainable, more efficient, accessible, and produce near zero greenhouse gas emissions. Electrochemical water splitting is considered as a highly viable and eco-friendly energy technology. Further, electrochemical carbon dioxide (CO₂) reduction reaction (CO₂RR) is a cleaner strategy for CO₂ utilization and conversion to stable energy (fuels). One of the critical issues in these cleaner technologies is the development of efficient and economical electrocatalyst. Among various materials, metal-organic frameworks (MOFs) are becoming increasingly popular because of their structural tunability, such as pre- and post- synthetic modifications, flexibility in ligand design and its functional groups, and incorporation of different metal nodes, that allows for the design of suitable MOFs with desired quality required for each process. In this review, the design of MOF was discussed for specific process together with different synthetic methods and their effects on the MOF properties. The MOFs as electrocatalysts were highlighted with their performances from the aspects of hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and electrochemical CO₂RR. Finally, the challenges and opportunities in this field are discussed.