电化学双电层电容器电极材料——豌豆荚基活性炭的制备与表征

以豌豆荚为碳源、ZnCl₂或KOH为活化剂制备了活性炭, 并用作双电层电容器的电极材料. 采用比表面及孔隙度分析仪表征了豌豆荚基活性炭的孔结构. 通过KOH或ZnCl₂活化后, 活性炭比表面积从1.69 m²·g^-1增大到2237或621 m²·g^-1. 采用循环伏安法和恒流充放电测试技术表征了豌豆荚基活性炭的电化学特性. 结果表明: 在6 mol·L^-1 KOH溶液中经KOH活化处理的活性炭的质量比电容高达297.5 F·g^-1, 并具有良好的充放电稳定性, 在5 A·g^-1的高电流密度下循环充放电500次后, 质量比电容仅衰减8.6%.

Preparation and Characterization of Peasecod-Based Activated Carbons as Electrode Materials for Electrochemical Double-Layer Capacitors

Activated carbons for electrochemical double-layer capacitor electrodes were prepared from peasecod-based carbons using ZnCl₂ or KOH as activating agents.The pore structures of the prepared activated carbon materials were characterized using N₂ adsorption.The specific surface area of the peasecod-based carbon materials increased obviously from 1.69 m²·g^-1 to 2237 m²·g^-1 by KOH activation and to 621 m²·g^-1 by ZnCI₂ treatment.The electrochemical properties of the prepared peasecod-based activated carbon materials were evaluated by cyclic voltammetry and galvanostatic charge-discharge,and a specific capacitance as high as 297.5 F·g^-1 in 6 mol·L^-1 KOH aqueous electrolyte was obtained for the KOH-treated carbon material.Additionally,the KOH-activated peasecod-based carbon material showed excellent long-term charge-discharge cycle stability and a 8.6%decrease in the specific capacitance was observed at a high current density of 5 A·g^-1 after 500 cycles.