Heterostructured CoO/Co3O4 nanowire array on Titanium mesh as efficient electrocatalysts for hydrogen evolution reaction

Heterostructured CoO/Co3O4 nanowire array on Titanium mesh (CoO/Co3O4 NA/Ti) is fabricated via a facile controllable calcination treatment of the Co3O4 precursor in a reducing atmosphere (H2/Ar) and applied as efficient electrocatalyst for hydrogen evolution reaction (HER). This electrode could catalyze the HER in 1.0 M KOH electrolyte with initial overpotential as low as 2.7 mV and need overpotential of 108 mV to approach 10 mA cm−2. Remarkably, it also shows high catalytical activity and long-time durability for HER both in phosphate buffer saline (PBS) and NaCl solution. This work may inspire the design of other high-performance three dimensional-nanostuctured (3D-nanostuctured) HER catalysts with abundant heterojunction interfaces.