Synthesis of binary metal phosphides heterostructures as a stable and efficient hydrogen evolution reaction electrocatalyst

Abstract In this work, we report a binary metal phosphides heterostructure (CoP-Cu3P) as an excellent catalyst for water splitting at all pH values. The electrocatalytic results exhibit that the optimized 70% CoP-30% Cu3P catalyst shows the remarkable catalytic performance for hydrogen evolution reaction (HER) at a wide pH values, evidenced by the overpotential values of 48 mV (0.5 M H2SO4), 83 mV (1 M KOH), and 96 mV (0.5 M phosphate buffer saline) at 10 mA cm-2, respectively. The electrocatalytic properties is observed to be small than those in case of pure Cu3P, and other CoP-Cu3P heterostructures. The exceptional catalytic performance is ascribed to their unique morphological and the synergistic effects between CoP and Cu3P, which provide abundant carrier charger transfer pathway and numerous surface catalytic active sites during the HER. Our strategy not only provides an outstanding electrocatalyst for HER but also presents a practical route to construct morphology-controlled binary metal phosphides heterostructure.