Fe Electron Center Local Regulation of CoFe‐Layered Double Hydroxides Nanosheets for Enhancing the Electrocatalytic Oxidation of Benzyl Alcohol

Abstract

AbstractReplacing sluggish oxygen evolution reaction (OER) with electrocatalytic oxidation (ECO) of alcohols was a promising hotspot due to its advantages of requiring low potential, inhibiting mixing of gases, and forming value‐added products. In the ECO of alcohols process, Fe electron centers of Fe‐based layered double hydroxides (LDHs) can regulate the d band of LDHs overlap, optimize the active local structure of LDHs, and then enhance the electrocatalytic oxidation performance. In this work, CoxFey‐LDHs nanosheets with different ratios of Co/Fe were prepared for selective ECO of benzyl alcohol (BA) to benzoic acid (BAC). Comprehensive characterizations revealed that the adjustment of bandgap and OH species adsorption of CoxFey‐LDHs resulted in the appropriate thermodynamic driving force, which improved the electrical conductivity of CoxFey‐LDHs and enhanced their ECO of BA. Especially, the as‐prepared Co3Fe1‐LDH showed intriguing electrocatalytic activity and only required a potential of 1.51 V (vs. RHE) to achieve a total current density of 50 mA cm−2 in alkaline solution containing 10 mM BA with a conversion (96.79 %) of BA and selectivity (94.93 %) of BAC, which was 60 mV lower than that of OER. After six cycles, Co3Fe1‐LDH still achieved 94.74 % conversion of BA and 92.10 % selectivity of BAC without significant degradation.