The interfacial aspect of Bi2O3/CeOx heterostructure catalysts for HCOOH production from CO2 electroreduction

Abstract

The advance of CO₂ electroreduction under ambient conditions is seriously impeded by the lack of an efficient electrocatalyst that can facilitate multiple proton-coupled electron-transfer processes and suppress the competitive hydrogen evolution reaction (HER). Herein, we report the synthesis of Bi₂O₃/CeO_x catalysts containing abundant heterointerfaces and oxygen vacancies by a two-step strategy. The prepared hybrid catalyst exhibits a superior selectivity of 98.28% for formic acid production and outstanding durability with an operation period of up to 32 h for CO₂ electroreduction. Theoretical calculations show that the interface in this structure provides efficient electron transfer rates, improves the adsorption of key adsorbates, and also alleviates the reaction energy potential barrier. The electron modulation induced by the interface achieves high selectivity and yield of HCOOH. This work provides new insights into the structural impact of rare earth oxides in Bi-based catalysts and provides strong support for the further development of catalysts containing rare earth metals.