The Controllable Preparation And Capacitance Propetries Of Cobalt Doped Manganese Oxide Electrode Materials

MnO2is a kind of promising electrode material for supercapacitors due to itsabundance, environmental friendly, non-toxic and high theoretical capacitance(1100~1300F/g). However, MnO2typically has low specific surface area, weakionic/electrical conductivity and electrochemical dissolution which are still challengesto overcome. The incorporation of other metal elements into MnO2is an effective wayto solve above problems. In this paper, cobalt-manganese oxide (CMO) compositeswere synthesized through adjusting electrodeposition parameters; correspondingelectrochemical characteristics were also discussed. The main experimental results areas follows:(1) CMOs were electrodeposited onto Ti substrates in0.1mol/L (CH3COO)2Mn+0.4mol/L (CH3COO)2Co electrolyte (pH=7). The results indicate that thespecific capacitance of CMOs is30%higher than that of pure MnO2, and better powerperformance and cycling stability are also achieved;(2) The influence of potentiostatic deposition on the physical property andcapacitive performance of CMOs were also studied. As the deposition potential rises,the Co content in CMOs also increase. However, the specific capacitances of CMOsfirst increase, and then gradually decrease;(3) The effects of (CH3COO)2Co concentration on the electrodepositon processof CMOs were also investigated. The results suggest that the Co content in CMOs increase with the increase of (CH3COO)2Co concentration in the electrolytes, and thepower performance and cycling stability gradually improve. However, the specificcapacitances of CMOs first decrease, and then increase.