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、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(FT-IR)光谱对磷酸促进淀粉分解的机理进行研究. 在6 mol·L-1 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, as an extensive biomass with natural globular structure, had been used to prepare microporous carbon microspheres by the promoting effect of H3PO4 on the pyrolysis of starch and the activation of KOH. Pore structure of samples was characterized by nitrogen adsorption/desorption at 77 K, and the results showed that micropores were the major component in samples. The micropore structure of samples was believed that it would afford enough accessible surfaces for capacitive storage. After the observation using scanning electron microscopy (SEM), it could be seen that the globular shape of starch was completely remained in the following carbonization and activation procedures, which was believed that H3PO4 played an important role in the process. The following Fourier Transform Infrared Spectrometer (FT-IR) characterization confirmed that the acceleration effect of H3PO4 on starch pyrolysis. The results of electrochemical measurement in 6 mol·L-1 KOH electrolyte showed that the product had excellent capacitive performances. Its specific capacitance was as high as 363.6 F·g-1 at a current density of 50 mA·g-1. And it exhibited excellent rate capability, which manifested that the cyclic voltammetry (CV) curve still remained rectangular and highly symmetric shape even when the scan rate reached as high as 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.