Hierarchically structured cobalt oxide (Co3O4): the morphology control and its potential in sensors.

A polyol process was developed to synthesize Co3O4 with controllable superstructures. By tuning the reaction conditions, the prepared Co3O4 were readily regulated in its morphologies, which could vary from nanosphere to two-dimensional (2D) nanoplates and 3D hierarchical structures, and finally to microspheres. The growth kinetics of such a process was also studied. The synthesized Co3O4 exhibited good sensitivity, remarkable selectivity, and high stability as an alcohol sensor material.