Facile synthesis of hierarchically porous Co3O4 nanowire arrays with enhanced electrochemical catalysis

We report a facile template-free procedure to synthesize freestanding Co3O4 nanowire arrays on nickel substrate. Cobalt oxalate nanowire arrays are formed by immersing the electrodeposited Co film in an oxalic acid solution, and their morphologies can be conveniently tuned by changing the composition of precursor solution. The thermal treatment of the cobalt oxalate nanowire arrays at 250 °C results in the formation of Co3O4 nanowire arrays. The as-synthesized Co3O4 nanowires exhibit a hierarchically porous structure inside their architectures. The Co3O4 nanowire array shows a much high sensitivity and a relatively wide linear range for the electrochemical detection of H2O2, resulting from the unique hierarchical nanostructure.

Graphical abstractWe report a facile template-free procedure to synthesize freestanding Co3O4 nanowire arrays on nickel subatrate. The as-synthesized nanowire arrays exhibit a hierarchically porous structure and a much higher sensitivity for the electrochemical detection of H2O2.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Freestanding Co3O4 nanowire arrays with large area are successfully fabricated. ► The facile two-step fabrication method for Co3O4 nanowire arrays is template-free. ► The Co3O4 nanowires exhibit a hierarchically porous nanostructure. ► The morphologies of the Co3O4 nanowire arrays can be conveniently tuned. ► The Co3O4 nanowire arrays show a much enhanced electrocatalytic activity.