In this paper, we report an effective, simple, and cost-effective strategy of electrochemical deposition to prepare hausmannite Mn_3O_4 thin films for the applications of supercapacitors. Various precursor concentrati...In this paper, we report an effective, simple, and cost-effective strategy of electrochemical deposition to prepare hausmannite Mn_3O_4 thin films for the applications of supercapacitors. Various precursor concentrations and deposition durations were manipulated to tailor the surface morphologies of Mn_3O_4 nanostructures and to optimize their electrochemical performances. The Mn_3O_4 samples prepared at 0.05 M Mn(NO3)2solution for 30 min delivered a large gravimetric specific capacitance of 210 F g-1at a current density of 0.5 A g-1, and a good rate capability over other samples. This superior electrochemical performance may be attributed to the improved electrode conductivity with increased accessible area for electrolytes ions. Furthermore, a nanocomposite film based on Mn_3O_4/carbon foam was fabricated by utilizing the developed optimized conditions. The Mn_3O_4/carbon foam films exhibit an excellent specific capacitance with negligible degradation in retaining specific capacitance values up to 4000 cycles. These findings could further broaden the applications of hausmannite Mn_3O_4 in electrochemical energy storage electrodes.展开更多
基金sponsored by the Australian Research Council(ARC)Discovery Projects of DP140104373 and DP150103006
文摘In this paper, we report an effective, simple, and cost-effective strategy of electrochemical deposition to prepare hausmannite Mn_3O_4 thin films for the applications of supercapacitors. Various precursor concentrations and deposition durations were manipulated to tailor the surface morphologies of Mn_3O_4 nanostructures and to optimize their electrochemical performances. The Mn_3O_4 samples prepared at 0.05 M Mn(NO3)2solution for 30 min delivered a large gravimetric specific capacitance of 210 F g-1at a current density of 0.5 A g-1, and a good rate capability over other samples. This superior electrochemical performance may be attributed to the improved electrode conductivity with increased accessible area for electrolytes ions. Furthermore, a nanocomposite film based on Mn_3O_4/carbon foam was fabricated by utilizing the developed optimized conditions. The Mn_3O_4/carbon foam films exhibit an excellent specific capacitance with negligible degradation in retaining specific capacitance values up to 4000 cycles. These findings could further broaden the applications of hausmannite Mn_3O_4 in electrochemical energy storage electrodes.