Ultrathin RhCu bimetallenes for the selective electro-oxidation of glycerol

Abstract

The selective electro-oxidation reaction represents an efficient and environmentally friendly pathway to produce value-added chemicals from glycerol. Herein, we introduce a high-temperature cyanogel-reduction method to synthesize ultrathin RhCu bimetallenes (RhCu-BMLs) with varying Rh/Cu molar ratios and investigate their catalytic activity and selectivity for the glycerol electro-oxidation reaction (GEOR). Among these catalysts, the as-prepared Rh3Cu1-BMLs exhibit outstanding mass activity (579.3 A gRh−1) for the GEOR under alkaline conditions, marking a 2.32-fold enhancement in mass activity (249.6 A gRh−1) relative to single-component Rh metallens (Rh-MLs). Meanwhile, both experimental characterizations and theoretical calculations reveal that Cu atoms can attenuate OH− adsorption and block the oxygen insertion reaction for the generation of tartaric acid due to the electronic effect. Consequently, Rh3Cu1-BMLs achieve a remarkable 78.7 % selectivity for generating glyceric acid during GEOR. This work provides an important reference for fabricating bimetallic Rh-based catalysts and advancing the selectivity and activity in GEOR.