Recent advance in electrocatalytic CO₂ reduction to ethanol over Cu based catalysts

The preparation of high value-added chemicals via electrocatalytic CO₂ reduction (CO₂ER) has become one of the highly hopeful tactics for achieving CO₂ greenhouse effect mitigation and sustainable energy development. Among various catalysts, Cu based materials have been widely investigated ascribed to their moderate adsorption of CO intermediate species compared to other metals, which facilitates C-C coupling for C2 products generation. Although ethanol has the advantages of high energy density and facile storage and transportation, its higher generation reaction energy barrier than ethylene cause to the low selectivity of ethanol. How to facilitate the catalytic performance of Cu based materials to achieve highly selective ethanol preparation is a significant challenge that urgently requires to be conquer. In the review, we summarize the latest outstanding researches on CO₂ER to ethanol over Cu based materials, and the modulation strategies of materials structure such as electronics, coordination, defects and interfaces are analyzed and classified. Besides, we deeply discuss the structure-activity relationship supported by the investigation of in situ characterizations and theoretical investigations. Furthermore, the integration study of electrolysis system including electrolyte, electrode, electrolyzer is outlined. Eventually, we propose the challenges for the future development and industrial scale application for highly efficient CO₂ER to ethanol.