Bimetal nickel–cobalt phosphide directly grown on commercial graphite substrate by the one-step electrodeposition as efficient electrocatalytic electrode

Abstract

It is challenging to find a method to obtain a catalyst with low cost and efficient multifunctional performances. Herein, in order to obtain the electrode with high-performance water splitting and non-enzymatic glucose detection, the commercial graphite sheet (GS) with excellent durability and electroconductivity was used as substrate material, and the non-noble ternary component Ni–Co–P catalyst with hierarchical architecture was fabricated on GS via a co-electrodeposition. The catalyst only required low overpotentials of 44.6, 76.5 and 49 mV to drive the current density of 10 mA cm−2 alongside with the smaller Tafel slopes of 39.2, 44.8 and 112 mV dec−1 for hydrogen evolution reaction (HER) in 1.0 M KOH, 0.5 M H2SO4 and 1.0 M PBS solution, respectively. For oxygen evolution reaction (OER), the catalyst demonstrated a low overpotential of 304 mV to achieve the current density of 20 mA cm−2 with excellent Tafel slope of 89.8 mV dec−1 in alkaline solution. Furthermore, the Ni–Co–P/GS electrode serving as non-enzymatic glucose sensor exhibited the superior electrocatalytic activity with an ultrahigh sensitivity of 7400 μA mM−1 cm−2, low detection limit of 0.425 μM (S/N = 3), and wide linear range (1–1200 μM).