Competing CO and HCOOH Pathways in CO₂ Electroreduction

Abstract

Abstract Human activities have significantly contributed to the increase in global carbon emissions, leading to adverse environmental effects such as global warming. Electrochemical reduction of carbon dioxide (CO 2 RR) presents a promising approach to mitigate carbon emissions. This process not only stores the low energy density renewable energies into high energy density chemical bonds, but also produces a variety of valuable products, including one‐carbon products like HCOOH and CO, as well as multi‐carbon products like CH 3 CH 2 OH and C 2 H 4 . Among them, HCOOH and CO can be produced with over 90 % selectivity on various catalysts, indicating their potential for large‐scale applications. However, the precise reaction pathways toward CO and HCOOH remain unclear, and the competition between these pathways often leads to low product selectivity. This review offers a comprehensive examination of the latest research on the selective reduction of CO 2 to CO and/or HCOOH, focusing on the development of the reaction mechanisms based on theoretical simulations and experimental investigations, and the application of catalysts designed to fine‐tune CO/HCOOH selectivity. Additionally, this review highlights the challenges and prospects for the further development and understanding of selective catalysts for CO and HCOOH production, aiming to provide valuable insights for future studies in this intriguing and significant research field.