In situ growth of Co3O4 nanoneedles on titanium mesh for electrocatalytic oxygen evolution

Designing high-efficient and low cost of electrodes with seamless integration of substrate and electrocatalyst particles is of significant concern for electrocatalytic water splitting. In this study, we actualized in situ growth of Co3O4 nanoneedles on titanium (Ti) mesh (denoted as Co3O4@Ti) by a simple combination of hydrothermal approach and subsequently calcination treatment under relatively low temperatures. The as-prepared Co3O4@Ti samples were evaluated as anodes for electrocatalytic oxygen evolution reaction (OER) in alkaline electrolyte. It demonstrates that the optimized Co3O4@Ti electrode displayed good OER activity with a small overpotential of 416 mV at a current density of 20 mA cm−2, which is on a par with commercial RuO2 catalyst (overpotential of 403 mV at 20 mA cm−2). The satisfactory OER performance of Co3O4@Ti electrode is largely attributed to the seamless integration of conductive Ti mesh substrate and the direct growth of Co3O4 nanoneedles on Ti mesh with sufficient active sites. This study suggests the potential application of Co3O4@Ti electrode as preeminent OER catalyst.