The electrochemical reduction of carbon dioxide (CO 2 RR) offers a sustainable approach for carbon recycling and the environmentally friendly production of chemicals. Its industrial applicability and eco-friendly nature have attracted widespread interest. Current CO 2 RR research aims to improve product selectivity and reaction kinetics. Significant progress has been achieved in the synthesis of multicarbon (C 2+ ) products. However, it remains difficult to precisely control the structure and electronic properties of catalysts. This challenge arises from complex reaction pathways, numerous reaction intermediates, and the high energy required for C-C bond formation. Therefore, a comprehensive overview of catalyst design strategies for C 2+ product synthesis is needed. This review focuses on the electrosynthesis of C 2+ products. First, we examine the physical adsorption of CO 2 on catalyst surfaces, its spatial arrangement, and the associated reaction energy barriers. Second, the formation of CO intermediates, as well as their adsorption and surface diffusion behavior, are discussed. These critical CO-related processes directly influence the final reaction products. Strategies that promote C-C bond formation are highlighted, including electronic structure modulation and the construction of interfacial synergistic sites. We also discuss how electrolytes, their interfacial behavior, and the gas-liquid-solid interface affect catalyst performance. Novel strategies for designing improved catalysts and reaction systems have emerged from recent advances in in situ characterization and theoretical simulation. This review provides a systematic framework and valuable insights for developing improved and controllable systems for C 2+ product synthesis. • Comprehensive review of electrocatalytic CO 2 reduction to C 2+ products. • Clarifies CO 2 activation mechanisms and key C-C coupling pathways. • Summarizes catalyst design strategies for high C 2+ selectivity. • Discusses the role of CO intermediates in reaction kinetics. • Outlines challenges in stability and large-scale CO 2 reduction.
Cao et al. (Wed,) studied this question.