Abstract

A new type of comb-like architecture with a hierarchical structure was prepared via a simple and effective hydrothermal strategy in the case of Co₃O₄. FESEM and TEM confirm the comb-like architecture of the hierarchical structure, and that the Co₃O₄ nanorods with secondary nanostructures are the building units. The studies of the sensing performance demonstrate that the as-synthesized comb-like Co₃O₄ nanostructures show excellent catalytic activity upon exposure to CO gases in comparison with rod-like Co₃O₄. Importantly, the comb-like Co₃O₄nanostructure-based sensor shows a fast response and recovery speed for CO gas. It is believed that the strategy of combining the hierarchical nanostructure and catalytic activity of Co₃O₄ nanomaterials can further provide potential for applications as real-time monitoring gas sensors.