铋基催化剂的合理设计和电催化二氧化碳转化

Rational design of bismuth-based catalysts for electrochemical CO_(2) reduction

近年来,化石能源的过度消耗导致大量的碳排放,由此引发了温室效应等环境问题,给人类社会的生存和发展带来巨大挑战.当前,通过不同的技术手段(生物催化、有机催化、光催化、电催化以及光电催化)已经能够实现二氧化碳的转化,从而为减少温室气体排放奠定了良好技术基础.其中,电催化二氧化碳还原技术具有生产装置简单、反应条件温和等优点,是实现碳中和的一种理想途径.电催化二氧化碳还原技术的核心在于制备出具有高活性、高选择性以及高稳定性的催化剂.铋基催化剂展现出了极佳的电催化二氧化碳还原性能,能够在大电流密度下实现甲酸的制备,同时具有极好的选择性和稳定性,因此,成为电催化二氧化碳还原领域的研究热点.本文综述了铋基材料在电催化二氧化碳还原领域的最新研究进展.首先介绍了铋基催化剂的种类(单原子、单质、合金、化合物、复合物)、制备方法(模板法、电沉积法、剥离法、湿化学法、MOF衍生法)以及调控策略(形貌工程、缺陷工程、组分调控工程、异质结工程),讨论了不同合成方法的优缺点和不同改性策略的差异,旨在阐明如何构建具有高活性、高选择性和高稳定性的铋基催化剂.同时,在催化剂的合成、优化与催化剂活性之间架起桥梁,即通过有效的合成方法和改性策略对催化剂形貌结构和电子结构进行调控,从而提高材料整体的电催化性能.为了更加深入地研究反应机理,对常用的原位表征技术(原位拉曼光谱、原位红外光谱、原位同步辐射光谱)进行了深入讨论.借助于原位表征技术,不但能够直接捕捉到催化剂表面和反应中间体之间的相互作用,还能够对反应过程中的催化剂表面价态和结构进行分析,对研究反应路径具有重要意义.此外,对电催化二氧化碳还原的工业化应用前景进行了探讨.最后,对电催化二氧化碳还原领域未来所面临的挑战与机遇进行了展望.

Sustainable conversion of carbon dioxide(CO_(2))to high value-added chemicals and fuels is a promising solution to solve the problem of excessive CO_(2) emissions and alleviate the shortage of fossil fuels,maintaining the balance of the carbon cycle in nature.The development of catalytic system is of great significance to improve the efficiency and selectivity for electrochemical CO_(2) conversion.In particular,bismuth(Bi)based catalysts are the most promising candidates,while confronting challenges.This review aims to elucidate the fundamental issues of efficient and stable Bi-based catalysts,constructing a bridge between the category,synthesis approach and electrochemical performance.In this review,the categories of Bi-based catalysts are firstly introduced,such as metals,alloys,single atoms,compounds and composites.Followed by the statement of the reliable and versatile synthetic approaches,the representative optimization strategies,such as morphology manipulation,defect engineering,component and heterostructure regulation,have been highlighted in the discussion,paving in-depth insight upon the design principles,reaction activity,selectivity and stability.Afterward,in situ characterization techniques will be discussed to illustrate the mechanisms of electrochemical CO_(2) conversion.In the end,the challenges and perspectives are also provided,promoting a systematic understanding in terms of the bottleneck and opportunities in the field of electrochemical CO_(2) conversion.