基于壳聚糖多孔碳的制备及电容性能研究

Preparation of Chitosan-Based Porous Carbon and Its Capacitance Performance

以壳聚糖为碳源和氮源,采用预碳化处理和KOH活化两步法制备了壳聚糖多孔碳材料,考察了活化剂KOH用量对电极材料形貌、结构以及电容性能的影响。结果表明:当KOH与预碳化壳聚糖质量比为0.6∶1时,制备的多孔碳材料KOH-CTS-0.6具有最优的电化学性能。KOH-CTS-0.6具有大比表面积(1348 m^2·g^-1),含有丰富的N、O元素(2.9%N和7.4%O)。在电流密度为0.5 A·g^-1时,KOH-CTS-0.6的比电容为235.2 F·g^-1,显示出优秀的倍率能力;在电流密度为10 A·g^-1的大电流时,其比电容依然高达178.6 F·g^-1。此外,该材料还具有良好的循环稳定性,500次循环后比电容保持率为94%。

Using chitosan as the carbon source and nitrogen source,we prepared chitosan porous carbon material by pre-carbonization treatment and KOH activation.Moreover,we investigated the effcts of the dosage of activator KOH on the morphology,structure and capacitance performance of the electrode material.The results show that,when the mass ratio of KOH to pre-carbonized chitosan is 0.6∶1,the porous carbon KOH-CTS-0.6 has the best electrochemical performance.Meanwhile,KOH-CTS-0.6 has a high specific surface area(1348 m^2·g^-1)and high N,O dopant concentrations(2.9%N and 7.4%O).The specific capacitance of KOH-CTS-0.6 is 235.2 F·g^-1 at 0.5 A·g^-1,which is still as high as 178.6 F·g^-1 at 10 A·g^-1.In addition,the material also has good cycling stability,and the specific capacitance retention rate is 94%after 500 cycles.