LDH-derived phosphide/N-doped graphene oxide hierarchical electrocatalyst for enhanced oxygen evolution reaction

Abstract

In this work, a highly efficient electrocatalyst Fe-Ni₂P/N-GO with hierarchical structure was developed through phosphating NiFe-based layered double hydroxide (LDH) supported by N-doped graphene oxide (GO), which was assembled by a solvothermal method. The LDH-derived Fe-Ni₂P/N-GO composites were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). Electrochemical measurements show that Fe-Ni₂P/N-GO has excellent oxygen evolution reaction (OER) performance with an overpotential of 269 mV at a current density of 10 mA cm⁻² and a Tafel slope of only 72 mV dec⁻¹. Besides, the composite exhibits a minimum charge transfer resistance compared with Fe-Ni₂P and Fe-Ni₂P/GO, and high long-term stability in alkaline solution.