An efficient amorphous ternary transition metal boride (WFeNiB) electrocatalyst for oxygen evolution from water

Abstract

To improve the overall efficiency of water electrolysis, it is urgent to develop an efficient and inexpensive catalyst toward the oxygen evolution reaction (OER). Transition metal borides are some of the most promising electrocatalysts for water splitting. Here, this work demonstrates that boron can promote the OER effect by regulating the interaction of reaction intermediates. Ternary transition metal borides can be prepared by in situ deposition on the surface of nickel foam through a simple chemical reduction method. Tungsten–iron–nickel–boron (W–Fe–Ni–B) nanoparticles show excellent OER activity and require an overpotential of 223 mV versus the RHE to reach 10 mA cm⁻² with a Tafel slope of 38.8 mV dec⁻¹. This catalyst experiences only a 6 mV shift after 12 hours of continuous testing in 1.0 M KOH solution, indicating good long-term stability. The combination of high catalytic activity, ease of preparation, and low cost makes WFeNiB/NF-based catalysts very promising OER catalysts. This high efficiency is mainly due to the catalyst's unique electronic structure, accelerated charge transfer, and hydro–hydro electronic surface. The significant stability is attributed to the increased corrosion resistance of borate species in the catalyst. The OER on the NiFeWB/NF surface involves metal adsorption and surface lattice oxygen. The metal elements acted as the active center, which triggered the OER together with lattice oxygen.