This paper reports enhancement in the specific capacitance of iron-doped manganese oxide ( $$\hbox {MnO}_{\mathrm {2}})$$ MnO 2 ) films, potentiostatically deposited on stainless-steel substrates. The properties of deposited films were investigated through cyclic voltammetry and galvanostatic charge/discharge characteristics. The specific capacitance, as determined through cyclic voltammetry and galvanostatic charge/discharge characteristics, respectively, was found to be 248.79 and 277.5 F $$\hbox {g}^{\mathrm {-1}}$$ g - 1 for undoped films, whereas it exhibited an increase with doping and was found to be 449.61 and 487.5 F $$\hbox {g}^{\mathrm {-1}}$$ g - 1 , respectively, corresponding to a dopant concentration of 4 atomic percentage. The electrochemical impedance data were fitted with a modified Randles equivalent circuit to find series resistance, charge-transfer resistance, double-layer capacitance and ion diffusion. According to electrochemical impedance spectroscopy, the enhancement of ion diffusion was found to be the major cause for enhancement in capacitive performance of the films.

中文翻译：

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增强铁掺杂氧化锰薄膜作为超级电容器电极的性能

本文报道了恒电位沉积在不锈钢基材上的铁掺杂锰氧化物 ($$\hbox {MnO}_{\mathrm {2}})$$ MnO 2 ) 膜的比电容的增强。通过循环伏安法和恒电流充电/放电特性研究了沉积膜的性质。分别通过循环伏安法和恒电流充放电特性确定的比电容为 248.79 和 277.5 F $$\hbox {g}^{\mathrm {-1}}$$ g - 1 对于未掺杂的薄膜，而它随着掺杂而增加，发现分别为 449.61 和 487.5 F $$\hbox {g}^{\mathrm {-1}}$$ g - 1 ，对应于 4 原子百分比的掺杂剂浓度. 电化学阻抗数据与改进的兰德尔等效电路相匹配，以找到串联电阻、电荷转移电阻、双层电容和离子扩散。根据电化学阻抗谱，发现离子扩散的增强是薄膜电容性能增强的主要原因。