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以自制活性炭(AC)为载体,(NH4)2S2O8为氧化剂、MnSO4为还原剂和锰源、(NH4)2SO4为模板试剂,通过原位水热沉积法制备了α-MnO2/AC系列复合电极材料.分别采用X射线衍射、扫描电子显微镜、N2吸附/脱附等方法对试样的晶型结构、形貌、比表面积和孔结构进行了表征;用循环伏安、恒流充放电和交流阻抗等电化学方法研究了材料的电化学性质.结果表明,在MnSO4浓度为0.075mol·L-1的水热条件下,获得了薄层晶状α-MnO2/AC复合材料.在电流密度为3mA·cm-2时,该材料电化学性能优异,比电容为374.5F·g-1,较沉积前AC的252.7F·g-1有显著提高,增幅为48.2%;α-MnO2/AC复合电极有良好的充放电特性和循环稳定性,经1000次恒流充放电测试,容量保持率达到95%。
A series of composite electrode materials of α-MnO2 / AC were prepared by in-situ hydrothermal deposition using activated carbon (AC) as carrier, (NH4) 2S2O8 as oxidant, MnSO4 as reductant and manganese source, (NH4) 2SO4 as template reagent The crystal structure, morphology, specific surface area and pore structure of the samples were characterized by X-ray diffraction, scanning electron microscopy and N2 adsorption / desorption respectively. The cyclic voltammetry, constant current charge-discharge and AC impedance The electrochemical properties of the materials were investigated by means of electrochemical methods.The results showed that the thin crystalline α-MnO2 / AC composites were obtained under hydrothermal conditions with MnSO4 concentration of 0.075mol·L-1. When the current density was 3mA · Cm-2, the electrochemical performance of this material was excellent, with a specific capacitance of 374.5F · g-1 and a significant increase of 252.7F · g-1, which was 48.2% Good charge and discharge characteristics and cycle stability, after 1000 times constant current charge and discharge test, the capacity retention rate of 95%.