摘要
Ca3CO4O9 (CCO) and Ca2.95K0.05Co4O9 (CKCO) powders have been prepared by the polyacrylamide gel method. CKCO shows increased capacity and better cycling stability compared with CCO. After cycled for 50 cycles at 0.5 C, CKCO retains a capacity of 223 mAh.g-1, almost twice than CCO. The electrochemical impedance spectroscopy (EIS) tests shows the CKCO sample has a lower initial charge transfer resistance (Rot) and undergoes smaller Rot change during cycling than the CCO sample, indicating improved electrochemical performance by K-doping.
Ca3CO4O9 (CCO) and Ca2.95K0.05Co4O9 (CKCO) powders have been prepared by the polyacrylamide gel method. CKCO shows increased capacity and better cycling stability compared with CCO. After cycled for 50 cycles at 0.5 C, CKCO retains a capacity of 223 mAh.g-1, almost twice than CCO. The electrochemical impedance spectroscopy (EIS) tests shows the CKCO sample has a lower initial charge transfer resistance (Rot) and undergoes smaller Rot change during cycling than the CCO sample, indicating improved electrochemical performance by K-doping.