Efficient electrocatalytic glucose oxidation coupled water electrolysis driven by the Ni-foam supported Ni-P nanowire arrays

Abstract

Using the thermodynamically favorable glucose oxidation reaction (GOR) to replace oxygen evolution reaction (OER) not only enables energy-efficient hydrogen production but also yields high-value products for water electrolysis. Herein, self-supported nickel phosphide nanowire arrays on Ni foam (Ni-P@NF) were facilely synthesized for GOR-assisted hydrogen production. Ni-P@NF can provide a current density of 100 mA cm-2 for GOR at 1.32 V (vs. RHE) and yield formic acid as the main product with the Faraday efficiency up to 97 %. The partial reconstruction of Ni-P into NiOOH on the surface during the GOR was recognized to comprehend the GOR catalytic mechanism. By coupling GOR and HER with Ni-P@NF as the electrodes, a low voltage of 1.43 V is required to drive the current density of 10 mA cm-2 for stable hydrogen generation and glucose conversion simultaneously. Thus, this work achieved energy-efficient hydrogen production and formic acid generation, providing of the well-aligned Ni-P nanowire arrays as the bifunctional catalysts for biomass oxidation-assisted water splitting.