以存在广泛的生物质原料马铃薯淀粉为前驱体,通过磷酸对淀粉分解的促进作用和KOH活化法制备微孔炭微球材料.采用77 K条件下的N2吸附/脱附和扫描电子显微镜(SEM)分别对所得样品的孔隙结构、形貌特征进行表征.采用傅里叶变换红外(FTIR)光谱对磷酸促进淀粉分解的机理进行研究.在6 mol·L“KOH电解质溶液中的电化学测试表明了所得微孔炭微球材料的优异电容特性.在50 mA·g-1的电流密度下,电容量为363.6 F·g-1.此外,该材料表现出了优异的倍率性能,在扫描速率为300 mV·s-1的条件下,所得循环伏安(CV)曲线仍能保持良好的矩形形状.电化学测试结果表明,马铃薯淀粉基微孔炭微球材料在高性能电化学电容器的电极材料领域具有广阔的应用前景.%Potato starch,an extensive biomass with natural globular structure,has been used to prepare microporous carbon microspheres by way of H3PO4 promotion of starch pyrolysis and activation by KOH.Nitrogen adsorption/desorption at 77 K indicate that micropores were the major structural component in the samples.The micropore structure provides accessible surfaces for capacitive storage.Scanning electron microscopy (SEM) revealed that the globular shape of starch remained after carbonization and activation procedures,due to the important role of H3PO4 in the process.Fourier transform infrared (FTIR) spectroscopy confirmed the acceleration effect of H3PO4 on starch pyrolysis.Electrochemical measurements in 6 mol · L-1 KOH electrolyte showed that the product had excellent capacitive charecteristica,with a specific capacitance as high as 363.6 F· g-1 at a current density of 50 mA · g-1.Furthermore,it exhibited a high charging rate such that the cyclic voltammetry (CV) curve still remained rectangular and highly symmetric shape even when the scan rate was 300 mV· s-1.All the results demonstrate that the potato starch-based microporous carbon is a promising electrode material for high performance electrochemical capacitors.
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