Surfactant-assisted microemulsion approach of chrysanthemum-like Co3O4 microspheres and their application in lithium-ion battery
Abstract A simple approach to synthesize Co 3 O 4 in mass production by using surfactant (CTAB) and cosurfactants (C 5 H 12 O and C 8 H 12 O) via the microemulsion treatment has been developed. By changing the reaction times, the prepared Co 3 O 4 was readily regulated in its morphologies varying from the chrysanthemum-like microspheres in bud to in full bloom. The sample reacted for 6 h maintains 565.5 mAh·g − 1 after 30 cycles at a current density of 60 mA·g − 1 , and 495.1 mAh·g − 1 after 40 cycles at a current density of 80 mA·g − 1 . Although the cycling performance at a current density of 50 mA·g − 1 started to fall off in the initial 20 cycles, the capacities were still comparable to the theoretical capacity of graphite (372 mAh·g − 1 ) after more than 100 cycles. The above 95% capacity retention after 20 cycles 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.