Construction of 2D C,N-co-doped ZnO/Co3O4 over Ni(OH)2 mesoporous ultrathin nanosheets on Ni foam as high-performance electrocatalysts for benzyl-alcohol oxidation and accelerating hydrogen evolution

Abstract

Electrocatalytic oxidation of benzyl alcohol at the anode to replace the traditional oxygen evolution reaction (OER) is a promising strategy to overcome its slow kinetics and promote the production of hydrogen with low energy consumption coupled with green synthesis of benzoic acid. Herein, we report the synthesis of 2D C,N-co-doped ZnO/Co₃O₄@Ni(OH)₂/NF heterostructure mesoporous nanosheets, which show high activity for benzyl alcohol oxidation with a conversion of 100%, a yield of benzoic acid over 99% and a faradaic efficiency of 97%. The C,N-co-doped ZnO/Co₃O₄@Ni(OH)₂/NF also demonstrated excellent stability and remained highly active after 8 cycles of testing due to the strong electronic interactions at the interface and its unique morphology with 2D hierarchical mesoporous nanosheets supported on a 3D nickel foam substrate. At a potential of 1.52 V vs. RHE, the hydrogen production reaches 3.32 mmol h⁻¹ cm⁻². This research provides strategies for building efficient and stable electrocatalysts for biomass conversion into value-added products and promoting green, low energy hydrogen production.