Engineering a localized electrostatic environment to enhance hydroxyl activating for electrocatalytic biomass conversion

The 5-hydroxymethylfurfural electrocatalytic oxidation reaction (HMFOR) is a sustainable and efficient route for converting biomass platform molecules into high-value chemicals. The HMFOR process involves the simultaneous oxidation of hydroxyl and aldehyde groups. Optimizing the reaction pathways by modulating the adsorption behavior of 5-Hydroxymethylfurfural molecules toward a higher conversion rate is vital for achieving an efficient HMFOR. In this study, the HMFOR electrocatalytic performance of NiO was enhanced by regulating the surface microenvironment through the decoration of NiO nanosheets with polypyrrole (PPy). Operando Fourier transform infrared spectroscopy, density functional theory calculation, and electrochemical behavior characterizations demonstrated that electropositive PPy can optimize the adsorption behavior of electronegative hydroxyl groups and modulate the reaction pathway toward the formation of 2,5-diformylfuran intermediates. By modulating the local microenvironment, the designed NiO-PPy catalyst showed excellent HMFOR performance with a threefold increase in current density. This study emphasizes the significance of the surface microenvironment in modulating reaction pathways to achieve selective biomass electrocatalytic conversion.