Advances in catalyst and reactor design for CO2 electroreduction to methanol

Abstract

The electroreduction of CO₂ to methanol constitutes an attractive strategy for sustainable energy storage and carbon recycling. Methanol is not only a versatile chemical feedstock but also a liquid energy carrier compatible with existing infrastructure. However, the multi-step proton–electron transfer process and competing reaction pathways significantly limit methanol selectivity and production rates. This review provides a critical overview of recent progress in CO₂-to-methanol electro-conversion, including both direct CO₂ reduction reactions and indirect CO reduction reactions. We focus on mechanistic insights, emphasizing key intermediates such as CO*, CHO*, and CH₃O*, and identify structure–activity relationships through operando characterization and density functional theory calculations. The discussion spans a wide range of catalyst platforms, from molecular complexes, single-atom catalysts, and nanoclusters to alloy materials, and explores strategies such as tandem catalysis and interface engineering to increase selectivity and efficiency. We further explore developments in gas-fed flow cells and membrane–electrode assemblies that enable high-rate, stable operation. Finally, we highlight current limitations in catalyst design and system integration and outline emerging strategies to enable scalable and carbon-neutral methanol electrosynthesis.