Unveiling the active sites of Ni–Fe phosphide/metaphosphate for efficient oxygen evolution under alkaline conditions

Abstract

The highly active and stable oxygen evolution reaction (OER) performance of Ni–Fe phosphide/metaphosphate (Ni_1−xFe_x-P/PO₃) can originate from in situ generated Fe doped γ-NiOOH. The optimized Ni_0.75Fe_0.25-P/PO₃@fCNT catalyst exhibits excellent activity and stability with an overpotential of 239 mV at 10 mA cm⁻² and a negligible decrease after 200 h continuous electrolysis in an alkaline solution.