Abstract: The electrocatalytic reduction of CO2 to valuable fuels and chemicals has great potential in mitigating global warming and effectively storing renewable energy, and has received extensive attention in recent years.Herein, first of all,this review briefly describes the research results of the reaction pathway of CO2 electrochemical reduction to different products in aqueous solution. Currently, the generation pathway of simple C1 products is relatively clear, but the reaction pathway for generating multi-carbon hydrocarbons and alcohols still lacks clear evidence and needs further exploration. Then, the recent advances of metal-based electrocatalytic materials for CO2 electrochemical reduction is described. Focusing on product selectivity, catalytic activity and stability, this review presents the research status of nanostructured metals, metal alloys, metal oxides, metal complexes, and singal atomic metal materials. Finally, the prospect of electrocatalytic CO2 reduction is proposed, and it is pointed out that continuously optimizing the performance of electrocatalytic materials is one of the main directions in future research, especially the single atomic catalysts which are expected to replace Au, Ag and other precious metals, as well as the copper-based materials that can efficiently produce multi-carbon products.At the same time, more accurate theoretical calculations combined with in-situ spectral characterizations, and the in-depth exploration of the mechanism of CO2 electrochemical reduction reactions will greatly promote the development of highly efficient electrocatalytic materials.

Key words: carbon dioxide, electrochemistry, reduction, metal-based material, reaction pathway

摘要： 电催化CO2还原为具有附加价值的燃料和化学品，在缓解全球气候变暖和有效储存可再生能源方面极具潜力，近年来受到了广泛的关注。本文首先简述了水溶液中CO2电化学还原为不同产物反应途径的研究成果，当前简单C1产物的生成路径较为清晰，但生成多碳烃类和醇类的反应途径尚缺乏明确的证据，需要进一步探索。然后综述了用于CO2电化学还原的金属基电催化材料的研究进展，聚焦于产物选择性，催化活性和稳定性，分别对金属纳米类、金属合金类、金属氧化物类、金属基复合物，以及最近出现的单原子金属催化材料的研究现状进行了介绍。最后，展望了电催化CO2还原的研究前景，指出不断优化电催化材料的性能是将来研究的主要方向之一，特别是有望取代Au、Ag等贵金属的单原子催化剂，以及能高效生成多碳产物的铜基材料；同时，更精确的理论计算结合原位光谱表征，深入探究CO2电化学还原反应的机理将极大地促进高效电催化材料的开发。

关键词: 二氧化碳, 电化学, 还原, 金属基材料, 反应途径