Template-synthesis and electrochemical properties of urchin-like NiCoP electrocatalyst for hydrogen evolution reaction.

Herein, we report a template-engaged strategy to fabricate urchin-like ternary metal phosphide (Ni 0.5 Co 0.5 P-300) as catalyst for hydrogen evolution reaction. The morphology and microstructure of Ni 0.5 Co 0.5 P-300 and its precursors were examined by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and micropore and chemisorption analyzer. Electrochemical properties were characterized by typical electrochemical methods, such as linear sweep voltammetry, cyclic voltammetry, chronoamperometry, chronopotentiometry and electrochemical impedance spectroscopy on a standard three-electrode system. Results show that the developed porous hierarchical 3D Ni 0.5 Co 0.5 P-300 catalyst has excellent electrocatalytic activity for hydrogen evolution in alkaline aqueous solution with onset overpotential of 26 mV and Tafel slope of 58 mV at the loading mass of 0.28 mg cm −2 . It only needs 87 mV to reach the current density of 10 mA cm −2 and can hold the nearly unchanged current density for 25 h amperometric test. Meanwhile, the Ni 0.5 Co 0.5 P-300 catalyst also exhibits good electrocatalytic properties for hydrogen evolution in 1 M PBS solution (pH = 7). These indicate that the Ni 0.5 Co 0.5 P-300 catalyst with urchin-like structure, bimetallic merit, and low cost may be a good candidate as electrocatalyst in practical application of hydrogen evolution. [ABSTRACT FROM AUTHOR]