How is rational design of electrocatalysts crucial for maximizing CO2 electroreduction performance

Electrochemical reduction of CO₂ (CO₂R) to valuable, carbon-neutral chemical feedstocks and storable fuels driven by renewable electricity offers a promising pathway to mitigate the greenhouse effect and reduce global demand for traditional fossil fuels, while simultaneously achieving sustainable energy and carbon neutrality. The CO₂R has a rich structure-sensitivity, and extensive efforts have been devoted to rationally controlling the size, morphology, dimension, chemical composition, surface structure, defects, etc., of the CO₂R catalysts for improving product selectivity, activity, and durability to approach the feasibility of practical applications (current density higher than 200 mA/cm² and lifetime beyond 1,000 hours). This presentation will discuss how the geometry and surface composition of copper- and tin-based electrocatalysts would maximize the CO₂ conversion to carbon monoxide and formic acid/formate in both common H-type cell and full electrolyzer cell configurations. Numerous spectroscopic, microscopic, and electrochemical characterization tools have been additionally utilized to correlate the structural, physico-chemical, and electronic properties with the CO₂R activity and selectivity. Our work provides additional design considerations of effective electrocatalysts for industrially relevant CO₂ reduction performance.