Interface engineering of the Ni(OH)2–Ni3N nanoarray heterostructure for the alkaline hydrogen evolution reaction

Abstract

It is highly attractive but challenging to design and develop noble-metal-free catalysts with outstanding electrocatalytic activity for the hydrogen evolution reaction (HER) in alkaline media. In this work, we demonstrate the development of Ni(OH)₂–Ni₃N nanoarrays on Ti mesh (Ni(OH)₂–Ni₃N/TM) as a three-dimensional (3D) HER catalyst in alkaline solutions. Due to the heterostructure from interface engineering, Ni(OH)₂–Ni₃N/TM shows excellent alkaline HER activity only requiring an overpotential of 72 mV to deliver the current density of 20 mA cm⁻² in 1.0 M KOH. Such an electrocatalyst also exhibits long-term electrochemical durability maintaining its activity for at least 25 h.