电催化氧气析出非贵金属催化剂的研究进展

电催化氧气析出反应是金属-空气电池充电过程和电催化分解水阳极的关键反应,对提高能量储存和转换效率、高效利用可再生清洁能源、缓解能源危机和环境污染具有重要作用。文章首先简要介绍了电催化氧气析出反应基本过程,随后综述了近年来用于电催化氧气析出反应的非贵金属催化剂的研究进展,重点讨论了过渡金属氧化物、过渡金属氢氧化物以及碳材料等非贵金属催化剂的研发情况。对这些催化剂的合成、结构及氧气析出催化性能进行了详细分析,也对这些催化剂的发展方向进行了简单分析。文章最后认为,新合成技术、新催化材料的发展以及氧气析出催化反应机理的阐明对发展高性能电催化氧气析出非贵金属催化剂将会起到极大的推动作用。     

多孔碳基非贵金属氧还原电催化剂研究进展

氧还原反应电催化剂在能量储存和转换中的应用受到了广泛关注，铂基贵金属催化剂因成本高、资源稀缺等缺点限制了其规模化应用。碳基非贵金属催化剂因价格低廉、反应活性好和抗甲醇渗透能力强等优点有望成为铂基催化剂的替代品。目前，文献报道的碳基催化剂主要通过调控活性位点的电子结构、增加活性位点密度与可接近性及调控碳/金属复合材料界面结构等策略提升其氧还原活性。从非金属元素掺杂碳基催化剂、碳基非贵金属单原子催化剂和碳基非贵金属纳米颗粒催化剂3个方面综述了碳基氧还原催化剂的研究进展，总结和指出了碳基催化剂面临的问题及挑战，并对催化剂的发展前景进行了展望。     

Ru基氮还原电催化剂性能调控策略

氨是重要的化学品以及理想的能源载体，人工合成氨主要来源于高能耗的Haber-Bosch(H-B)工艺。相比而言，电催化合成氨以N₂和H₂O为原料，实现了温和条件下产氨。Ru基催化剂在氮还原(NRR)过程中表现出优异的催化活性，但由于较为稀缺限制了其发展。基于此，首先概述了NRR的反应机制并对现有的Ru基合成氨电催化剂进行了系统的介绍；详细分析了性能提升策略(结构调控、表/界面工程、缺陷工程)，如何调控活性组分或电子结构，进而提升催化剂的性能；最后分析了Ru基催化剂所面临的挑战。旨在通过Ru基催化剂性能提升策略，实现贵金属Ru的高效利用，并为其他NRR催化剂的开发设计提供指导。     

锌空气电池双功能阴极催化剂研究进展

可充电锌空气电池(ZAB)被认为是具有前景的储能设备之一.阴极氧还原反应和氧析出反应(ORR和OER)动力学缓慢,限制ZAB的实际应用,开发出高活性催化ORR/OER双功能阴极电催化剂尤为重要.综述了非贵金属双功能阴极电催化剂,包括无金属碳材料催化剂、过渡金属催化剂和过渡金属-氮掺杂碳材料组合催化剂,讨论几种催化剂催化...     

Ir基催化剂用于CO选择性催化还原NO的研究进展

针对具有烟温低、氧含量高和CO浓度大等特征的固定源烟气（钢铁烧结/球团烟气和焦化烟气等）脱硝领域,CO选择性催化还原NO _x （CO-SCR）技术具有良好的发展前景。Ir基贵金属催化剂因其在CO-SCR反应体系中表现出了良好的抗氧能力和较高的催化活性成为催化脱硝领域研究的热点之一。本文重点总结了单一载体、复合载体与复合活性组分三类Ir基催化剂在CO-SCR脱除NO _x 中的催化性能,同时从制备条件和反应条件两大方面归纳了其对Ir基催化剂的CO-SCR脱硝性能的影响,简要阐述了Ir基催化剂表面反应机理,并对未来研究工作进行了展望,指出采用多种手段对催化剂进行改性,并通过降低Ir负载量、反应温度窗口以及提升其催化活性等方式来降低成本,为实现Ir基催化剂CO-SCR工业化应用提供借鉴。     

我国科学家推进贵金属催化剂研究

<正>苏州大学材料与化学化工学部黄小青课题组在二维铂基纳米催化剂的制备和催化氧还原反应方面取得重要进展。相关成果日前发表于《科学》。研究有效地解决了模型催化中电化学界面的瓶颈问题。据介绍,贵金属催化剂可广泛应用于环境保护、能源转换、食品加工等领域。铂基纳米材料是目前ORR性能最好的电化学催化剂。由于其在地壳中的储存量较少,价格昂贵,导致其在燃料电池领域的大规模应用受阻。如何提高贵金属催化剂的     

羰基化合物直接还原胺化合成伯胺催化剂研究进展

胺类化合物是一类重要的化工原料和中间体，在农药、医药、染料、高分子聚合物等领域有着广泛的应用。通过羰基化合物（醛或酮类）的还原胺化来制备胺类化合物是当前的研究热点。研究表明，贵金属基和非贵金属基的多相和均相催化剂均能够高效催化醛或酮类的还原胺化反应。本文对近年来羰基化合物直接还原胺化（或一锅法）合成伯胺的研究现状进行了综述，包括还原胺化反应、催化剂、反应条件、底物适用范围和催化作用机制等，其中重点阐述了直接还原胺化催化剂的研究进展。文章指出：通常多相催化剂具有活性高以及可重复使用等优点，而均相催化剂的优势在于催化效率高，伯胺选择性高；另一方面，以Pd、Rh、Ru等为代表的贵金属催化剂催化性能优异，但价格昂贵，因此可采用Co、Ni等性能同样优异但价格相对低廉的非贵金属催化剂以降低成本。文中提出，催化效率高、反应条件温和、普适性高的羰基化合物还原胺化催化剂应成为未来重点研究方向。     

5-羟甲基糠醛催化氢化制备2,5-呋喃二甲醇的研究进展

2,5-呋喃二甲醇（BHMF）在合成树脂、药物等方面具有重要应用。随着化石资源的日益缩减,由可再生的生物质基平台分子5-羟甲基糠醛（HMF）催化制备BHMF引起人们的广泛关注。本文在总结了HMF及BHMF物化性质的基础上,介绍了HMF在分子氢、醇类、甲酸3种不同的氢供体中催化加氢制备BHMF的研究近况,总结了贵金属、非贵金属、双金属或多金属协同催化体系在该加氢反应中的应用进展,同时分析了反应过程中温度、时间、催化剂载体、反应溶剂种类及酸值等因素对HMF转化率及BHMF得率的影响。最后对HMF催化转化制备BHMF的研究前景进行了总结和展望,提出了使用醇类代替氢气作为氢供体,开发非贵金属及金属协同催化体系将是该选择性氢化反应的重要研究方向之一。     

挥发性有机物燃烧催化剂的研究进展

挥发性有机物（VOCs）是主要大气污染物质，也是形成PM_2.5和臭氧的重要前体。强化挥发性有机物控制，是改善大气环境的重要途径。催化燃烧（氧化）被认为是去除VOCs最有效的方式之一，本文综述了VOCs催化燃烧常用的贵金属催化剂、非贵金属催化剂。其中，贵金属催化剂主要包括基于Pd、Pt、Ru等的催化剂，非贵金属催化剂主要包括Mn、Co、Ce、Zr等的氧化物，通常贵金属催化剂具有比非贵金属更高的氧化活性和稳定性，但对于含氮VOCs非贵金属催化剂（Mn、Cu）具有更好的氮气选择性，Cr基催化剂对于含氯VOCs燃烧具有更好的效果。此外，还重点讨论了载体、分散度、催化剂制备方法对贵金属催化剂性能的影响，并对发展VOCs氧化催化剂的研究提出了展望。     

原子层沉积构建高性能催化剂的研究进展

催化剂在能源化工领域具有重要应用,精确设计及调控催化剂结构可有效改善催化剂的性能。原子层沉积（ALD）是基于饱和自限制的气-固界面反应技术,被认为是调控活性相的组成、尺寸及落位最有效的方式之一。本文综述了ALD技术在调控催化剂活性相结构、设计多功能型催化剂及提高催化剂稳定性等方面的研究进展。重点阐述了ALD技术在调控催化剂活性相颗粒尺寸和表界面结构、设计多功能核壳结构及多孔材料限制性催化剂等方面的应用。ALD设计及控制金属沉积的技术优势可实现对催化剂活性、产物选择性和稳定性的有效调控,但其在复杂结构载体的沉积机理方面仍未得到充分研究,是今后研究工作重点。此外,利用ALD技术设计结构清晰、功能多样的催化剂来进一步提高催化性能及认识其反应机理也是未来的研究方向。     

电解海水催化剂的设计与改性

电解海水是一种可再生、可持续、低成本且节约淡水资源的氢气生产方案。因此,针对天然海水或盐水电解质的析氢反应（HER）和析氧反应（OER）,设计开发高效、稳定的电催化剂具有良好的应用前景。为了深入了解海水电解所面临的现状和挑战,本文对电催化分解海水催化剂的设计思路与改性方法进行了系统的回顾和总结。首先详细讨论了电解海水中析氢反应、析氧反应、析氯反应的基本原理。随后对最近报道的在海水中能够稳定运行的HER和OER电催化剂进行了汇总和分析。针对阴极催化剂,分别概述了高效贵金属基电催化剂和低成本过渡金属基电催化剂。针对阳极催化剂,主要讨论了取得较大进展的镍基催化剂,随后对镍基之外的其他电催化剂进行对比补充。文章最后对电解海水催化剂目前所面临的挑战和发展方向进行了总结和展望,基于现有分析认为,在未来的研究中需要进一步探索新型电解海水催化剂的种类和结构,开发更高效稳定的阴极和具有更高OER选择性的阳极电催化剂,以满足分解海水电催化剂工业化应用的要求。     

Interfacial engineering of transition-metal sulfides heterostructures with built-in electric-field effects for enhanced oxygen evolution reaction

Developing highly efficient,durable,and non-noble electrocatalysts for the sluggish anodic oxygen evo-lution reaction (OER) is the pivotal for meeting the practical demand in water splitting.However,the cur-rent transition-metal electrocatalysts still suffer from low activity and durability on account of poor interfacial reaction kinetics.In this work,a facile solid-state synthesis strategy is developed to construct transition-metal sulfides heterostructures (denoted as MS2/NiS2,M =Mo or W) for boosting OER electro-catalysis.As a result,MoS2/NiS2 and WS2/NiS2 show lower overpotentials of 300 mV and 320 mV to achieve the current density of 10 mA·cm-2,and smaller Tafel slopes of 60 mV·dec-1 and 83 mV-dec-1 in 1 mol·L-1 KOH,respectively,in comparison with the single MoS2,WS2,NiS2,as well as even the bench-mark RuO2.The experiments reveal that the designed heterostructures have strong electronic interac-tions and spontaneously develop a built-in electric field at the heterointerface with uneven charge distribution based on the difference of band structures,which promote interfacial charge transfer,improve absorptivity of OH,and modulate the energy level more comparable to the OER.Thus,the designed transition-metal sulfides heterostructures exhibit a remarkably high electrocatalytic activity for OER.This study provides a simple strategy to manipulate the heterostructure interface via an energy level engineering method for OER and can be extended to fabricate other heterostructures for various energy-related applications.     

Metal phosphonate-derived cobalt/nickel phosphide@N-doped carbon hybrids as efficient bifunctional oxygen electrodes for Zn−air batteries

The exploration of efficient bifunctional electrocatalysts for oxygen reduction reaction and oxygen evolution reaction is pivotal for the development of rechargeable metal–air batteries. Transition metal phosphides are emerging as promising catalyst candidates because of their superb activity and low cost. Herein, a novel metal phosphonate-derived cobalt/nickel phosphide@N-doped carbon hybrid was developed by a carbothermal reduction of cobalt/nickel phosphonate hybrids with different Co/Ni molar ratios. The metal phosphonate derivation method achieved an intimately coupled interaction between metal phosphides and a heteroatom-doped carbon substrate. The resultant Co₂P/Ni₃P@NC-0.2 enables an impressive electrocatalytic oxygen reduction reaction activity, comparable with those of state-of-the-art Pt/C catalysts in terms of onset potential (0.88 V), 4e^‒ selectivity, methanol tolerance, and long-term durability. Moreover, remarkable oxygen evolution reaction activity was also observed in alkaline conditions. The high activity is ascribed to the N-doping, abundant accessible catalytic active sites, and the synergistic effect among the components. This work not only describes a high-efficiency electrocatalyst for both oxygen reduction reaction and oxygen evolution reaction, but also highlights the application of metal phosphonate hybrids in fabricating metal phosphides with tunable structures, which is of great significance in the energy conversion field.     

质子交换膜电解水制氢技术的发展现状及展望

氢能是支撑起智能电网和可再生能源发电规模化的最佳能源载体,而电解水制氢是实现制氢规模化的重要途径。在多种电解水制氢技术中,质子交换膜电解水技术由于具备电流密度大、产氢纯度高、响应速度快等优势,吸引了科学界和工业界的广泛重视。本文首先介绍了质子交换膜电解池的结构组成以及各组成的主要作用,对比分析了碱性电解池、固体氧化物电解池与质子交换膜电解池的技术差异,并结合电解水析氢反应以及析氧反应的机理阐释,分别介绍了两步半反应的常用催化剂;然后,从最初的实验室研究阶段到目前兆瓦级别的质子交换膜电解水系统,回顾了该技术的发展历程以及应用现状;其次,从制氢成本、电堆性能及电堆寿命等多角度分析目前该技术面临的瓶颈问题;最后,根据质子交换膜电解池的技术优势,并针对上游间歇性可再生能源的需求以及和下游产业的联合应用,对其未来前景进行了展望。     

Spinel CoFe2O4 /carbon nanotube composites as efficient bifunctional electrocatalysts for oxygen reduction and oxygen evolution reaction

In the development of fuel cells, it is the key to large-scale commercialization of fuel cells to rationally design and synthesize efficient and non-noble metals-based bifunctional electrocatalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). In this paper, spinel CoFe₂O₄/carbon nanotube composites (CoFe₂O₄/CNTs/FA) were synthesized by solvothermal and calcination method. XRD, TEM, XPS and BET characterizations indicate that the addition of complexing agent fumaric acid can improve the crystal growth kinetics and morphology of CoFe₂O₄/CNTs nanohybirds. The as-synthesized CoFe₂O₄/CNTs/FA pyrolyzed at 500 °C have an outstanding bifunctional catalytic activity for ORR and OER with the potential of 1.62V (vs. RHE) at a current density of 10 mA/cm² and half-wave potential E_1/2 = 0.808V (vs. RHE) in alkaline electrolyte, respectively. It is obviously better than unloaded CoFe₂O₄ nanoparticles and commercial CNTs. CoFe₂O₄/CNTs/FA also exhibit better methanol tolerance ability and durability than commercial Pt/C and RuO₂ catalyst. This investigation broadens an idea of simple compounding of spinel with carbon-based materials to improve electrochemical properties.     

双功能yolk-shell钴@钴氮碳掺杂氧电极催化剂

以ZIF-67为模板,通过表面原位聚合多巴胺,与金属Co²⁺发生强烈螯合,释放出有机配体,得到中空的金属-有机结构材料（Co-PDA）。通过900℃高温处理得到类似蛋黄（yolk-shell）结构的金属氮掺杂碳材料（Co@Co-N/C）。这种特殊结构的材料具有优异的氧还原（ORR）和析氧反应（OER）电催化活性,在0.1 mol/L KOH电解液中,其ORR的半波电位为0.81 V,Tafel斜率为60 mV/dec;在电流密度为10 mA/cm²时,其OER过电位为390 mV,Tafel斜率为71 mV/dec,总的氧电极催化活性为0.82 V,是一种优良的双功能氧电极催化剂。     

PtCo-based nanocatalyst for oxygen reduction reaction: Recent highlights on synthesis strategy and catalytic mechanism

Oxygen reduction reaction over Pt-based catalyst is one of the most significant cathode reactions in fuel cells. However, low reserves and high price of Pt have motivated researchers worldwide seeking enhanced utilization efficiency and durability by doping non-noble metals to form Pt-based alloy catalysts. Alloying Pt with Co has been recognized as one of the most effective approaches to achieve this goal.PtCo bimetal combination is one of the most promising candidates to synthesize highly effi...     

Recent advance in transition metal oxide-based materials for oxygen evolution reaction electrocatalysts

Using renewable energy to electrolyze water to produce hydrogen is the only way to realize a green hydrogen economy. At present, the large-scale application of this technology is encumbered by the relatively low activity and stability of oxygen evolution reaction (OER) electrocatalysts. The use of cost-effective catalysts can significantly reduce the overpotential of oxygen evolution and improve the economics and power conversion efficiency of the hydrogen production process from electrolysis of water. Among the various candidates, the transition metal oxide-based (TMOs) materials show great prospects and receive ever-increasing research interests because of their diversified surface/bulk structures, natural enrichment, easy accessibility and environmental friendliness. In this review, the latest tactics aiming at enhancing activity via increasing the accessible active sites and promoting intrinsic activity have been summarized. In addition, with special emphasis on the long-term stability, the up-to-data strategies for elevating the stability are introduced. Finally, conclusions and perspectives are also presented.     

过渡金属氧化物催化析氧反应研究进展

利用可再生能源电解水制氢，是实现绿色氢能经济的必由之路。现阶段，电解水过程的阳极析氧反应过电位较高，催化剂性能不稳定，制约着该技术的工业化应用。使用经济高效的催化剂，可显著降低析氧过电位，提高电解水制氢过程的经济性和电能转化效率。在各类析氧催化剂材料中，过渡金属氧化物（TMOs）由于晶体结构多样、储量丰富、环境友好、易于制备以及活性较高等优点，受到了越来越多的关注。本文从活性和稳定性出发，总结分析了近年来过渡金属氧化物催化析氧反应的研究进展，并对其未来的发展提出了建议与展望。     

Polymer electrolyte membrane water electrolysis: status of technologies and potential applications in combination with renewable power sources

Technological improvements in polymer electrolyte membrane water electrolysers (PEMWEs) are promoted by their exciting possibilities to operate with renewable power sources. In this paper, a synopsis of the research efforts concerning with the development of electrocatalysts, polymer electrolytes and stack hardware components is presented. The most challenging problem for the development of PEMWEs is the enhancement of oxygen evolution reaction rate. At present, there are no practical alternatives to noble metal-based oxide catalysts such as IrO₂ and RuO₂. As well as carbon supported Pt nanoparticles are the benchmark cathode catalysts for hydrogen evolution. High noble metal loading on the electrodes and the use of perfluorosulfonic membranes significantly contribute to the cost of these devices. Critical areas include the design of appropriate mixed electrocatalysts and their dispersion on low cost Ti-oxide like supports to increase catalyst utilization. Moreover, the development of alternative membranes with enhanced mechanical properties for high pressure applications, proper conductivity and reduced gas cross-over is strongly required. This latter aspect is also addressed by the development of proper recombination catalysts. The development of anodic mixed non-noble transition metal oxides with spinel or perovskite structure and proper resistance to chemical degradation in the acidic environment and electrochemical corrosion is also an active area of research. Similarly, efforts are also being addressed to Pd and Ru based cathode formulations with cheaper characteristics than Pt. Whereas, concerning with stack hardware, cost reduction may be addressed by replacing Ti-based diffusion media and bipolar plates with appropriate and cost-effective stainless steel materials with enhanced resilience to chemical and electrochemical corrosion. Regarding the combination with renewable power sources, PEM electrolysers can find suitable applications for peak shaving in integrated systems grid connected or in grid independent operating conditions where hydrogen generated through electrolysis is stored and then via fuel cell converted back to electricity when needed or used to refill fuel cell-based cars. Hydrogen is the most promising clean energy carrier to accomplish the sustainable production of energy and a synergy among hydrogen, electricity and renewable energy sources is highly desired.