Rational Design and Recent Advances of Cu, Sn, and Cu–Sn Composite Materials for Electrochemical CO2 Reduction

Abstract

The electrochemical reduction of carbon dioxide (CO2) into value-added chemicals, enabled by appropriate catalysts, offers a promising approach to mitigate CO2 emissions while converting it into a valuable chemical resource. Among various catalyst materials, copper (Cu), tin (Sn), and their composites or alloy (Cu–Sn) counterparts have attracted extensive attention due to their earth abundance, low cost, and environmental friendliness. This review provides a comprehensive overview of recent progress in Cu- and Sn-based electrocatalysts, including single metals/oxides, bimetallic metals/oxides, and strategies to improve performance, such as heteroatom doping, carbon support selection and modification, and molecular catalyst design. Catalyst morphologies, including nanowires, nanosheets, nanocubes, and other nanostructures, are also summarized in relation to their electrocatalytic performances. Moreover, surface modification strategies that enhance the selectivity toward C2+ products are discussed. Finally, the current challenges and opportunities for the rational design of Cu-, Sn-, and Cu–Sn-based catalysts are outlined, providing guidance for their future development toward efficient and selective CO2 electrochemical reduction.