Boosting Electrochemical Kinetics of NiCo₂ via MoO₂ Modification for Biomass Upgrading Assisted Hydrogen Evolution

Abstract

Converting renewable biomass into value-added chemicals is a promising strategy to reduce the dependence on fossil fuels. The development of efficient, stable, and cost-effective nonprecious metal catalytic materials is significant for biomass upgrading. Herein, the 5-hydroxymethylfurfural (HMF) dehydrogenation kinetics on the NiCo 2 nanowire is tuned by MoO 2 for the HMF electrooxidation (HMFOR)-assisted H 2 evolution (HER). The introduction of MoO 2 could accelerate electron/proton transfer during HMFOR and optimize the adsorption behavior of HMFOR/HER intermediates, which would also lower the energy barrier for dehydrogenation of 5-hydroxymethyl-2-furanoic acid to 5-formyl-2-furancarboxylic acid by weakening the C–H/O–H bond. Consequently, NiCo 2 @MoO 2 /NF exhibits improved HMFOR/HER activity ( E ±10 = 1.20 V RHE /–31 mV RHE ), HMFOR kinetics ( k NiCo2@MoO2/NF /k NiCo2/NF = 2.57), and 2,5-furandicarboxylic acid selectivity (99.2%). When coupled as a two-electrode system, it requires only 1.25 V to achieve 10 mA cm –2 for HMFOR-assisted H 2 production. This work provides a strategy for the design of advanced catalysts for biomass upgrading assisted H 2 production.