LAUSR

Abstract This work reports the preparation of 3D porous nickel-sulfur electrode for hydrogen evolution reaction (HER). The construction of the 3D porous structure is achieved by hydrogen bubbles dynamic templates, prepared from Cu electrodeposition at high current density. Subsequently, a nickel-sulfur film is electrodeposited on the 3D porous copper structure. The nickel-sulfur film with high crystal Ni 3 S 2 content is achieved only through controlling deposition current. And the relationship between crystal structure and deposition current has been revealed. The porous crystal Ni 3 S 2 electrode is significantly active for HER with a lower onset overpotential and an additional negative potential leading to a rapid increase in the cathodic current. And the developed electrode shows a lower charge transfer resistance for HER, which takes both advantages of high intrinsic activity and large real surface area. Besides, the electrode shows a higher electrochemical stability during the long-term electrolysis test.