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.