Photo-enhanced electrocatalysis of sea-urchin shaped Ni3(VO4)2 for the hydrogen evolution reaction

Abstract

Efficient and stable electrocatalysts for the hydrogen evolution reaction (HER) are central to the development of renewable energy. In this study, a photoresponse electrocatalyst Ni₃(VO₄)₂ with a sea-urchin shaped structure was prepared by a facile solvothermal procedure. Numerous thin nanoflakes on the spherical surface increased active sites which play a promoting role in the photocatalytic or electrocatalytic reactions. Under visible light irradiation, the sea-urchin shaped Ni₃(VO₄)₂ demonstrated improved HER activity without using any cocatalysts, featured by a small overpotential of −90 mV at 10 mA cm⁻², a high current density, a small Tafel slope of 50 mV per decade and good stability in 0.5 M H₂SO₄. The results may offer a simple and mild methodology for the preparation of HER electrocatalysts exhibiting excellent photo-enhanced electrocatalytic activity.