Dispersive non-noble metal phosphide embedded in alumina arrays derived from layered double hydroxide precursor toward efficient oxygen evolution reaction and biomass upgrading

Abstract

Exploring high-performance and stable electrocatalysts for the oxygen evolution reaction (OER) is critical for the conversion and storage of renewable energy. Herein, a novel strategy was developed for the construction of dispersive nickel phosphide (Ni₂P) embedded in two-dimensional (2D) amorphous alumina arrays on three-dimensional (3D) nickel foam (NiP–Al₂O₃/NF) electrocatalysts via the reduction of a layered double hydroxide (LDH) precursor. Owing to its unique 3D nano/micro-architecture, multi-porous structure, interconnected conductive skeleton, and highly dispersive Ni₂P active sites, the NiP–Al₂O₃/NF electrocatalyst exhibited excellent OER activity with overpotential as low as 193 mV at 10 mA cm⁻² in a 1.0 M KOH solution and superior catalytic activity for the oxidation of 5-hydroxymethylfurfural in alkaline media. Density functional theory calculations demonstrated that the introduction of P to Ni could effectively reduce the OER overpotential. Furthermore, benefiting from the flexibility of compositional tailoring of both the brucite-like layers and interlayer anions of LDHs, the synthesis strategy presented here can be easily extended to the fabrication of various nanostructured noble-metal-free functional materials, which are expected to have wide application prospects in many domains, especially in catalysis.