Temperature-dependent pathways in carbon dioxide electroreduction

Temperature affects both the thermodynamics of intermediate adsorption and the kinetics of elementary reactions. Despite its extensive study in thermocatalysis, temperature effect is typically overlooked in electrocatalysis. This study investigates how electrolyte temperature influences CO2 electroreduction over Cu catalysts. Theoretical calculations reveal the significant impact of temperature on *CO and *H intermediate adsorption thermodynamics, water microenvironment at the electrode surface, and the electron density and covalent property of the C-O bond in the *CH-COH intermediate, crucial for the reaction pathways. The theoretical calculations are strongly verified by experimental results over different Cu catalysts. Faradaic efficiency (FE) toward multicarbon (C2+) products is favored at low temperatures. Cu nanorod electrode could achieve a FEC2 value of 90.1% with a current density of 400 mA cm 2 at 3 degrees C. FEC2H4 and FEC2H5OH show opposite trends with decreasing temperature. The FEC2H4/FEC2H5OH ratio can decrease from 1.86 at 40 degrees C to 0.98 at 3 degrees C. (c) 2025 Science China Press. Published by Elsevier B.V. and Science China Press. All rights are reserved, including those for text and data mining, AI training, and similar technologies.