还原气氛、助催化剂对SrTiO3光催化分解水制氢性能的影响

采用水热法制备了SrTiO3光催化材料,研究了在还原气氛下不同处理时间对SrTiO3光催化分解水制氢性能的影响;此外还研究了单一和复合助催化剂以及担载方法对光解水制氢性能的影响。结果表明:还原气氛中处理1h的样品,其制氢速率比未经处理的样品提高了近40%;担载单一助催化剂比复合助催化剂效果更好;光沉积Pt助催化剂样品具有最高的光催化活性。     

可见光下光催化分解水制氢的研究进展

利用太阳能驱动光催化反应制备氢气成为了目前的研究热点。综述了近年来在可见光下光催化分解水制氢的研究进展,着重介绍了固溶体光催化剂、非金属化合物型光催化剂、Z型光催化系统及新型助催化剂的最新研究成果,并展望了光催化制氢的发展。     

化学所在石墨烯电催化分解水析氢领域取得新进展

正电催化分解水制氢是减少环境污染及实现可再生清洁能源的重要途径。开发高效、稳定的制氢催化剂具有重要的科学价值和现实意义。石墨烯材料因其具有比表面积大、导电性好、稳定性高等优势,被广泛应用于电催化分解水制氢的研究中。     

非贵金属Co5.47N/N-rGO助催化剂增强TiO2光催化制氢性能

高效稳定的光催化剂或助催化剂研究一直是光催化领域的重要课题之一。本研究以氧化石墨烯、氯化钴和2-甲基咪唑为前驱体, 结合液相法和氨气氮化法制备了负载Co_5.47N的氮掺杂还原氧化石墨烯(Co_5.47N/N-rGO), 其中Co_5.47N高度分散、晶粒尺寸为10~20 nm。Co_5.47N/N-rGO可以作为助催化剂有效地改善商业二氧化钛(P25)的光催化分解水制氢性能, 当其质量分数为25%时, 催化剂的制氢性能可以达到11.71 mmol·h ^-1·g ^-1, 相比于纯P25提升了90倍, 与负载贵金属Pt的性能相当(11.88 mmol·h ^-1·g ^-1), 并且具有良好的稳定性。本研究为高效非贵金属助催化剂的研制提供了新思路。     

MOF基的光解水制氢催化剂研究进展

随着能源枯竭和环境污染问题日益严重,人们不得不将目光转向更加清洁环保的氢能源。光解水制氢技术是一种获取氢能源经济且清洁的理想方式,通过光催化手段将太阳能转化为化学能也是一种很有前景的技术手段。然而如何选取高效、经济的光催化剂是制氢最关键的环节。金属-有机框架(Metal-organic frameworks, MOFs)由于比表面积大、孔尺寸可调节、结构易于修饰及活性位点丰富等特点,使其成为光解水制氢理想的光催化剂候选材料。国内外学者就MOFs光解水制氢开展了大量的研究,并且取得了丰硕的成果。本论文综述了MOF基材料作为催化剂在光解水制氢领域的研究进展,总结了MOFs作为催化剂的优点和局限性,并对MOFs及其相关材料在光催化水解制氢领域的发展前景提出展望,以期对未来研究提供参考。     

金属有机框架材料在光催化制氢领域的应用

太阳能光催化分解水是实现绿色、高效生产可持续能源氢气的重要途径之一,而光催化剂的设计和开发在这一过程中起着关键作用。常用的传统半导体光催化剂目前面临的主要挑战包括阳光利用率不足、载流子易复合、活性位点暴露不足等问题,因此,开发新型、高效光催化剂的研究显得尤为重要。具有类半导体行为的金属有机框架(metal-organic frameworks, MOFs)材料,由于其超高的比表面积、孔隙率及高规整度,近年来在光催化产氢领域受到越来越广泛的关注。介绍了MOFs材料的结构特点及在光催化制氢领域中应用的独特优势,基于光催化机理从改善光吸收、促进电荷分离和加速表面反应几个方面,总结了提高MOF基光催化剂活性的策略,并对其应用前景进行了展望。     

双功能过渡金属化合物的构建与应用

氢能作为一种清洁能源,通过不可储存的可再生资源发电催化水分解制氢,被认为是解决能源和环境危机最有前景的技术之一。电解水反应必须使用高效催化剂降低析氢反应(HER)和析氧反应(OER)的过电势,因此开发高效、廉价的HER-OER双功能催化剂具有简化整体系统和降低成本的优势。综述报道了近3年HER-OER双功能催化剂的最新发展,对几种主要类型的双功能全电解水催化剂的合成、催化活性、稳定性及增强活性的方法进行了详细讨论,并对双功能催化剂面临的挑战和发展方向进行了展望。     

光催化分解水制氢催化剂的研究进展

面对石油、煤炭和天然气等不可再生能源的日益枯竭和其带来的环境污染问题,人们不得不寻找新的化石燃料替代品。氢能是一种清洁、可再生燃料,在未来具有替代化石燃料的巨大潜力。利用光催化活性材料光解水制氢是一种将太阳能转化为氢能的有效方式。然而,用于光解水制氢的大多数催化材料仍然存在对太阳能利用率低且光生电子和空穴对易于复合等问题,这些问题导致产氢效率较低,从而严重限制了光催化剂的实际运用。因此,开发具有低成本、环境友好、可见光响应和良好性能的光催化剂则成为当前光解水制氢催化剂的研究重点。目前用于光解水制氢的催化剂主要包括金属氧化物、金属硫化物、金属氮(氮氧)化物、石墨碳氮化物和新型异质结构光催化剂等。其中,金属氧化物中TiO_2作为光解水制氢的传统光催化剂而被广泛研究;金属硫化物因其窄带隙和良好的带隙位置,在光解水制氢中表现出良好的催化活性,其研究主要集中在CdS、ZnS及其固溶体上;金属氮(氮氧)化物具有理想的可见光全解水能带结构,需对其进行改性从而体现出全解水活性;石墨碳氮化物是一种新型的非金属可见光催化剂,由于其在制氢方面的巨大潜力而受到了人们的关注。此外,将半导体复合构建二元或多元能够高效分离光生载流子的新型异质结构复合光催化剂也是一个非常活跃的研究领域。本文结合近年来国内外光解水制氢催化剂的研究现状,综述了光解水制氢催化剂的研究进展,分别对每类催化剂的特点和研究内容进行了总结,并介绍了某些催化剂的制备工艺和改性策略,最后总结了当前光解水制氢催化剂所面临的问题并对其未来的发展方向进行了展望,以期为设计制备高效、稳定的光催化制氢材料提供参考。     

利用太阳能制氢的方法及发展现状

发展清洁可再生能源是人类面临的巨大技术挑战,氢气作为一种理想的清洁能源,其制取及储运技术近年来都取得了很大进展。综述了利用太阳能分解水制氢的基本途径及发展现状,主要包括电解水制氢及人工模拟光合作用制氢、半导体光解水及其催化剂以及最有希望实现的高温热化学循环分解水制氢技术。     

TiO2光催化剂的非金属离子修饰改性及其在水盐体系中的应用

金属离子掺杂、非金属离子掺杂、离子注入以及染料光敏化等方法都可不同程度地实现TiO2可见光化,其中非金属掺杂TiO2可见光催化剂其可见光活性是不以损失UV光激发效率而可以独立存在的.本文重点介绍了近年来非金属掺杂修饰改性TiO2光催化剂及本课题组在染料敏化半导体光催化制氢研究方面所取得的一些研究成果,对非金属离子改性TiO2光催化剂的效能进行了整理分类.构建以天然海水和盐湖卤水为应用背景的无电子给体的无机水盐廉价制氢反应体系,是光催化走向实用化的一个新探索.本文回顾了无机水盐制氢反应体系构建方面的研究成果,并对未来光催化分解水的研究工作进行了展望.     

太阳能光解水制H2催化剂研究进展

氢气是未来人类社会可持续发展的理想能源,光解水制H2的关键是具有高性能的光催化剂.论述了光解水的机理;综述了近年来有关TiO2、过渡金属氧化物、层状金属氧化物、光生物催化剂以及其它新的复合物在光解水方面的研究进展;讨论了提高其光催化反应活性的途径;对存在的问题和前景进行了展望.     

Ultrathin Co(Ni)-doped MoS<Subscript>2</Subscript> nanosheets as catalytic promoters enabling efficient solar hydrogen production

The design of efficient artificial photosynthetic systems that harvest solar energy to drive the hydrogen evolution reaction via water reduction is of great importance from both the theoretical and practical viewpoints.Integrating appropriate co-catalyst promoters with strong light absorbing materials represents an ideal strategy to enhance the conversion efficiency of solar energy in hydrogen production.Herein,we report,for the first time,the synthesis of a class of unique hybrid structures consisting of ultrathin Co(Ni)-doped MoS2 nanosheets (co-catalyst promoter) intimately grown on semiconductor CdS nanorods (light absorber).The as-synthesized one-dimensional CdS@doped-MoS2 heterostructures exhibited very high photocatalytic activity (with a quantum yield of 17.3％) and stability towards H2 evolution from the photoreduction of water.Theoretical calculations revealed that Ni doping can increase the number of uncoordinated atoms at the edge sites of MoS2 nanosheets to promote electron transfer across the CdS/MoS2 interfaces as well as hydrogen reduction,leading to an efficient H2 evolution reaction.     

Fundamental aspects and recent advances in transition metal nitrides as electrocatalysts for hydrogen evolution reaction: A review

With increasing human population, sustainable energy production has become one of the most persistent and significant problems of the current century. Hydrogen is considered to be the best clean fuel for future energy requirements. As a substitute of fossil fuels, hydrogen is readily provided by an electrocatalytic hydrogen evolution reaction that splits water molecules. Conventional electrocatalysts based on noble metals are scarce and considerably expensive for large-scale hydrogen production, necessitating the search for low-cost earth abundant alternatives. In this context, transition metal nitrides have gained considerable attention as competent electrocatalytic materials for water splitting. This review presents recent advancements and progress on transition metal nitrides as efficient and cost-effective electrocatalysts for hydrogen production. After overviewing the fundamental aspects of the hydrogen evolution reaction (HER), the review discusses various synthetic strategies for developing transition metal nitrides. Discussed herein are titanium nitrides, vanadium nitrides, iron nitrides, nickel nitrides, molybdenum nitrides, tungsten nitrides, and their composite electrocatalysts employed in HER applications. Some design viewpoints for improving the electrocatalytic activity are systematically proposed. Finally, the review discusses challenges and future perspectives for the advancement of non-noble metal-based electrocatalysts.     

光解水制氢半导体光催化材料的研究进展

自从Fujishima-Honda效应发现以来,科学研究者一直努力试图利用半导体光催化剂光分解水来获得既可储存而又清洁的化学能--氢能.近一二十年来,光催化材料的研究经历了从简单氧化物、复合氧化物、层状化合物到能响应可见光的光催化材料.本文重点描述了这些光催化材料的结构和光催化特性,阐述了该课题的意义和今后的研究方向.     

基于电催化析氧反应的非贵金属催化剂研究进展

在全球变暖和能源危机的背景下，能源问题已成为全球各国战略安全的重要组成部分。氢能作为可持续的新型可再生清洁能源，对缓解全球性能源短缺具有重要意义。在众多制氢候选方案中，电解水制备氢气被认为是最可靠、最可行的途径之一。但在电解过程中，反应动力学极为迟缓的阳极析氧反应(Oxygen evolution reaction,OER)严重制约着整体反应效率。因此，开发成本相对低廉、催化剂性能优异、耐久性好的高效OER电催化剂，从而提高电解水制氢工艺技术的能源转换效果受到了广泛关注。本文首先简要阐述了析氧反应的反应机制及其性能的评价参数，接着对非贵金属催化剂的研究进行分类讨论，并列举了提高催化性能的策略和方法，最后对设计新型催化剂进行展望。     

Transition‐Metal‐Based Electrocatalysts as Cocatalysts for Photoelectrochemical Water Splitting: A Mini Review

Converting solar energy into hydrogen via photoelectrochemical (PEC) water splitting is one of the most promising approaches for a sustainable energy supply. Highly active, cost‐effective, and robust photoelectrodes are undoubtedly crucial for the PEC technology. To achieve this goal, transition‐metal‐based electrocatalysts have been widely used as cocatalysts to improve the performance of PEC cells for water splitting. Herein, this Review summarizes the recent progresses of the design, synthesis, and application of transition‐metal‐based electrocatalysts as cocatalysts for PEC water splitting. Mo, Ni, Co‐based electrocatalysts for the hydrogen evolution reaction (HER) and Co, Ni, Fe‐based electrocatalysts for the oxygen evolution reaction (OER) are emphasized as cocatalysts for efficient PEC HER and OER, respectively. Particularly, some most efficient and robust photoelectrode systems with record photocurrent density or durability for the half reactions of HER and OER are highlighted and discussed. In addition, the self‐biased PEC devices with high solar‐to‐hydrogen efficiency based on earth‐abundant materials are also addressed. Finally, this Review is concluded with a summary and remarks on some challenges and opportunities for the further development of transition‐metal‐based electrocatalysts as cocatalysts for PEC water splitting.     

2D Transition‐Metal‐Dichalcogenide‐Nanosheet‐Based Composites for Photocatalytic and Electrocatalytic Hydrogen Evolution Reactions

Hydrogen (H₂) is one of the most important clean and renewable energy sources for future energy sustainability. Nowadays, photocatalytic and electrocatalytic hydrogen evolution reactions (HERs) from water splitting are considered as two of the most efficient methods to convert sustainable energy to the clean energy carrier, H₂. Catalysts based on transition metal dichalcogenides (TMDs) are recognized as greatly promising substitutes for noble‐metal‐based catalysts for HER. The photocatalytic and electrocatalytic activities of TMD nanosheets for the HER can be further improved after hybridization with many kinds of nanomaterials, such as metals, oxides, sulfides, and carbon materials, through different methods including the in situ reduction method, the hot‐injection method, the heating‐up method, the hydro(solvo)thermal method, chemical vapor deposition (CVD), and thermal annealing. Here, recent progress in photocatalytic and electrocatalytic HERs using 2D TMD‐based composites as catalysts is discussed.     

A review:Synthesis,modification and photocatalytic applications of ZnIn2S4

Solar energy is an ideal energy source for solving energy shortages and serious environmental problems.In the past few decades,photocatalytic technology which uses solar energy to deal with the above prob-lems has caused great interest.ZnIn2S4,as a layered ternary metal chalcogenide compound,has a series of advantages such as the wide light absorption range and adjustable bandgap.It has been applied in the different fields of photocatalysis in recent years.This review introduced the crystal structures and growth mechanism of ZnIn2S4 and summarized the preparation methods of ZnIn2S4.Also,the promoted strate-gies of ZnIn2S4 based photocatalytic system and their applications in the pollutant removal,hydrogen evolution,reduction of CO2,nitrogen fixation,and chemical synthesis was summarized.Furthermore,the challenges and development directions of the current ZnIn2S4 based photocatalytic system were proposed.It is hoped that this review will help researchers design a better ZnIn2S4 based photocatalytic system.