催化学报 ›› 2021, Vol. 42 ›› Issue (8): 1287-1296.DOI: 10.1016/S1872-2067(20)63740-8

• 综述 • 上一篇    下一篇

非晶纳米材料用于电解水的研究进展

郭成英a, 史艳梅a, 卢思宇c, 于一夫a,*(), 张兵a,b,#()   

  1. a天津大学理学院化学系, 分子+研究院, 天津 300072
    b天津大学教育部合成生物前沿科学中心, 天津市分子光电子科学重点实验室, 天津 300072
    c郑州大学化学学院, 河南 郑州 450001
  • 收稿日期:2020-09-11 接受日期:2020-09-11 出版日期:2021-08-18 发布日期:2020-12-10
  • 通讯作者: 于一夫,张兵
  • 作者简介:#. 电话:(022)27406140; 传真: (022)27403475; 电子信箱: bzhang@tju.edu.cn
    *. 电话: (022)27406140; 传真: (022)27403475; 电子信箱: yyu@tju.edu.cn
  • 基金资助:
    国家自然科学基金(21701122);天津市自然科学基金(17JCJQJC44700)

Amorphous nanomaterials in electrocatalytic water splitting

Chengying Guoa, Yanmei Shia, Siyu Luc, Yifu Yua,*(), Bin Zhanga,b,#()   

  1. aInstitute of Molecular Plus, Department of Chemistry, School of Science, Tianjin University, Tianjin, 300072, China
    bTianjin Key Laboratory of Molecular Optoelectronic Sciences, Frontiers Science Center for Synthetic Biology (Ministry of Education), Tianjin University, Tianjin 300072, China
    cCollege of Chemistry, Zhengzhou University, Zhengzhou 450001, Henan, China
  • Received:2020-09-11 Accepted:2020-09-11 Online:2021-08-18 Published:2020-12-10
  • Contact: Yifu Yu,Bin Zhang
  • About author:# +86-22-27406140; Fax: +86-22-27403475; E-mail: bzhang@tju.edu.cn
    *. Tel: +86-22-27406140; Fax: +86-22-27403475; E-mail: yyu@tju.edu.cn
    Bin Zhang (Department of Chemistry, School of Science, Tianjin University) received his Ph.D. degree from the University of Science and Technology of China in 2007 (with Prof. Yi Xie). He carried out postdoctoral research at the University of Pennsylvania (July 2007 to July 2008, with Prof. Ritesh Agarwal) and worked as an Alexander von Humboldt fellow at the Max Planck Institute of Colloids and Interfaces (August 2008 to July 2009, with Dayang Wang). Currently, he is a Fellow of the Royal Society of Chemistry (FRSC), a senior member of the Chinese Chemical Society, and a professor at Tianjin University. He mainly focuses on the controlled chemical transformation synthesis of designed targeted nanomaterials for water splitting and water-involved transfer hydrogenation reactions. In January 2021, he joined in Youth Editorial Board of the Chinese Journal of Catalysis.
  • Supported by:
    This work was supported by the National Natural Science Foundation of China(21701122);the Natural Science Foundation of Tianjin City(17JCJQJC44700)

摘要:

电催化水分解产氢作为一种有前途的制氢技术被全世界研究者广泛关注. 然而, 此领域仍然缺少一种高效、无污染的催化剂, 以降低能耗, 提升反应动力学, 进而推进电解水的实际应用. 近年来研究发现, 具有短程有序、长程无序特征的非晶纳米材料在电解水领域表现出极其优异的性能. 有趣的是, 固有的无序结构赋予了非晶纳米材料丰富的高活性位点. 鉴于此, 本文综述了非晶纳米材料的制备策略以及表征方法, 并且对其高活性来源进行了系统地分析. 此外, 本文通过分析近几十年的研究成果指出了非晶纳米材料在电解水领域面临的挑战和应用前景.
非晶纳米材料的合成方法主要分为两类: 直接合成和间接合成. 直接合成主要包括: 电沉积、光化学金属-有机沉积、气溶胶-喷雾辅助法、反胶束溶胶-凝胶法、水热法、共沉淀法和氧化还原法. 其中, 气溶胶-喷雾辅助技术可以通过控制母液中金属离子的浓度精准地控制非晶纳米材料中各种金属元素的组成, 从而有目的地调控并优化催化活性. 间接合成主要分为原位转化和非原位转化. 原位转化是指晶体材料在反应过程中表面会原位转化为非晶结构作为反应的真实活性物质. 非原位转化是指当纳米材料尺度非常小时, 高表面能将会破坏材料的结晶度得到非晶材料. 另外, 非晶材料长程无序的特点给其表征带来极大挑战. 目前, 对于非晶材料表征的一般流程是: 首先通过X射线粉末衍射确定非晶结构, 并通过透射电子显微镜以及扫描电子显微镜探索其形貌结构; 再通过选区电子衍射以及高角度环形暗场扫描透射电子显微镜进一步确定非晶结构; 然后, 通过能谱、电感耦合等离子体发射光谱和X射线光电子能谱分析其化学组成及化学态; 最后, 采用拉曼光谱和同步辐射数据提供晶体结构信息.
本文对非晶纳米材料高活性的起源进行了探究. 在电解水领域, 非晶纳米材料通常表现出优于晶体材料的性能. 优异的活性与活性位点数量的增多以及活性位点活性的提升有关: (1)非晶纳米材料具有长程无序的特征, 可以暴露更多活性位点, 并且其表面存在的大量悬挂键也可以作为活性位点; (2)非晶纳米材料的活性位点可以拓展至催化剂体相内部, 大幅提升了活性位点数量; (3)非晶纳米材料结构灵活性高, 活性位点在催化反应过程中可以转变成任意形状, 提升了活性位点的活性; (4)非晶纳米材料的高韧性和应变能力赋予其较高的稳定性.
非晶纳米材料已广泛应用于电解水领域, 但仍然存在一些问题: (1)非晶纳米材料由于原子级结构不确定, 其电催化机理很难探究; (2)理论模拟作为研究电化学反应途径的有力工具很难应用于非晶纳米材料的研究; (3)随着无序程度的增加, 活性位点数量和活性逐渐增加, 但电导率逐渐下降. 尽管如此, 由于非晶纳米材料结构灵活性高和自重组能力快速, 人们对其在电解水领域的研究兴趣越来越大, 并且该领域显示出良好的应用前景, 高效非晶纳米材料的设计合成及其催化机理的研究将成为今后研究的重点.

关键词: 非晶, 电催化, 水分解, 合成, 纳米材料

Abstract:

Electrochemical water splitting, as a promising method for hydrogen production, has attracted significant attention. However, the lack of an electrocatalyst with a small energy loss and fast reaction kinetics has hindered the development of this technology. Amorphous nanomaterials with short-range order and long-range disorder features have recently shown superior activity compared to their crystalline counterparts in water electrolysis. The enhanced activity arising from their intrinsic disordered structure results in more active sites and a higher intrinsic activity of such sites. In this regard, this review is aimed at summarizing the progress in amorphous electrocatalysts for water splitting. First, the synthesis strategies for amorphous electrocatalysts are discussed. Characterization tools for amorphous nanomaterials are then summarized. Moreover, the origin of the enhanced activity and stability of amorphous nanomaterials is analyzed. Finally, the current challenges and promising opportunities in this research area are discussed. This review aims to provide a guide for designing and developing amorphous nanomaterials with a fascinating electrocatalytic water splitting performance.

Key words: Amorphous, Electrocatalysis, Water splitting, Synthesis, Nanomaterials