Facilitating Formate Selectivity via Optimizing eg* Band Broadening in NiMn Hydroxides for Ethylene Glycol Electro‐Oxidation

Abstract

AbstractEthylene glycol electro‐oxidation reaction (EGOR) on nickel‐based hydroxides (Ni(OH)2) represents a promising strategy for generating value‐added chemicals, i.e. formate and glycolate, and coupling water‐electrolytic hydrogen production. The high product selectivity was one of the most significant area of polyols electro‐oxidation process. Yet, developing Ni(OH)2‐based EGOR electrocatalyst with highly selective product remains a challenge due to the unclear cognition about the EGOR mechanism. Herein, Mn‐doped Ni(OH)2 catalysts were utilized to investigate the EGOR mechanism. Experimental and calculation results reveal that the electronic states of eg* band play an important role in the catalytic performance and the product selectivity for EGOR. Broadening the eg* band could effectively enhance the adsorption capacity of glyoxal intermediates. On the other hand, this enhanced adsorption could lead to reduced side reactions associated with glycolate formation, simultaneously promoting the cleavage of C−C bonds. Consequently, the selectivity for formate was notably augmented by these enhancements. This work offers new insights into the regulation of catalyst electronic states for improving polyol electrocatalytic activity and product selectivity.