Surfactant-assisted microemulsion approach of chrysanthemum-like Co3O4 microspheres and their application in lithium-ion battery

Abstract

A simple approach to synthesize Co3O4 in mass production by using surfactant (CTAB) and cosurfactants (C5H12O and C8H12O) via the microemulsion treatment has been developed. By changing the reaction times, the prepared Co3O4 was readily regulated in its morphologies varying from the chrysanthemum-like microspheres in bud to in full bloom. The sample reacted for 6h maintains 565.5mAh·g−1 after 30cycles at a current density of 60mA·g−1, and 495.1mAh·g−1 after 40cycles at a current density of 80mA·g−1. Although the cycling performance at a current density of 50mA·g−1 started to fall off in the initial 20cycles, the capacities were still comparable to the theoretical capacity of graphite (372mAh·g−1) after more than 100cycles. The above 95% capacity retention after 20cycles is believed to benefit from unique structural features, particularly clusters of nanofibers. The chrysanthemum-like nanostructures with larger BET specific surface area created an easier and shorter diffusion pathway for ionic and electronic diffusion, which resulted in good power performance.