The mesoporous manganese dioxide (MnO2) materials were synthesized by the calcinations of manganese carbonate (MnCO3) precursors in air atmosphere at 300, 350 and 400℃. The slurries of MnO2 and binder were sprayed on the quartz electrodes. Quartz crystal microbalance (QCM) was conducted with cyclic voltammetry to analyze the electrochemical behaviors of the three MnO2 samples in 0.1 mol/L sodium sulfate (Na2SO4). The mass of the three samples were generally increased during potential cycling, especially in the first stage, which suggested that an irreversible reaction process occurred. The as-synthesized MnO2 at 300℃ had the better electrochemical stability and capacity retentivity. The three materials were assembled to (-) active carbon/MnO2 (+) supercapacitors and the charge-discharge tests were conducted. The results showed that 35％-40％ capacity loss was occurred in the initial cycling, and the total discharge capacities of MnO2 formed at 300℃, 350℃, 400℃ were 15.9, 12.9, 11.7 mA h/g, respectively. The detection results of QCM method were consistent with that of the charge-discharge tests, suggesting that this QCM method could be used for distinguishing the electrochemical performance of mesoporous MnO2 materials.%以碳酸锰(MnCO3)为前体,空气氛围下采用不同温度(300℃、350℃、400℃)煅烧, 制备了3种介孔二氧化锰(MnO2)材料,分别与粘结剂混合喷涂至石英晶片作为电极,利用石英晶体微天平(QCM)监测了3种材料在0.1 mol/L Na2SO4溶液中随循环伏安过程的电化学性能变化.分析结果表明,3种材料在首圈循环中都呈现出显著的质量增加,发生了不可逆反应过程; 300℃煅烧制备的MnO2材料具备更好的电化学稳定性和容量保持能力.将300℃, 350℃和400℃煅烧的MnO2各自作为正极与活性炭负极组成超级电容器, 进行充放电测试,首圈均有35％～40％的容量损失; 三者稳定循环时放电容量分别为15.9, 12.9和11.7 mA h/g.QCM的分析与充放电测试结果相一致,表明QCM可用于比较不同介孔二氧化锰材料的电化学性能.
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