Dealloyed NiTiZrAg as an efficient electrocatalyst for hydrogen evolution in alkaline seawater

Abstract

Seawater, one of nature's most bountiful resources, holds promise as a valuable and inexhaustible raw material for hydrogen production through water electrolysis. However, to combat chloride corrosion and maintain a stable operating state, it is essential to design strong and effective electrocatalysts appropriate for the hydrogen evolution reaction (HER). Herein, we demonstrate that Ni40Ti20Zr38Ag2 alloy, after the successive arc-melting, melt-spinning, and dealloying treatments, generates a distinctive nanosheet structure. In alkaline seawater electrolyte (1 M KOH + natural seawater), this materials for HER not only could achieve a smaller overpotential of 69 mV driving 10 mA cm−2, but also possess excellent stability including the 10 mA cm−2 current density over 24 h and 3000 cycles measurement. This is mainly attributed to the array of cascading interconnected nanosheets and the incorporation of Ag, as well as the resulting electron transfer and changes in the chemical state of the elements on the catalyst surface. This work proposes a novel design strategy for alloy materials for preparing an efficient HER electrocatalyst in alkaline seawater.