采用HClO4对石油焦进行氧化改性,按照碱碳比为3:1的比例将改性石油焦活化成活性炭,产物标记为OAC-3。作为对比,按照碱碳比4:1将石油焦活化成活性炭,产物标记为AC-4。采用XRD、I2吸附、N2吸附和循环伏安研究HClO4氧化对石油焦结构和产物活性炭性能的影响。结果表明,HClO4氧化将石油焦石墨微晶d(002)晶面层间距由0.344nm提高到0.353nm,同时将晶粒粒径由2.34nm减小到1.75nm。AC-4和OAC-3的比表面积分别为2929和3058m2/g,在0.5mV/s的扫描速率下,其比电容分别为361.3和392.7F/g;基于OAC-3的超级电容器具有更好的功率特性。
Petroleum coke (PC) was modified by HClO4 oxidization. Activated carbons (ACs) were prepared using a mass ratio of KOH/modified PC of 3 : 1 ( denoted OAC-3 ) and a KOH/PC mass ratio of 4 : 1 ( denoted AC-4 ) for comparison. XRD, I2 adsorption, N2 adsorption and cyclic voltammograms were used to investigate the influence of HC104 oxidization on the structure of the PC and the performance of the resultant AC. Results indicated that HClO4 oxidization increased the d(002) of microcrystalline PC from 0.344 to 0.353 nm and decreased Lc from 2.34 to 1.75 rim. The specific surface areas of AC-4 and OAC-3 were 2 929 and 3 058 m2/g, respectively. AC-4 and OAC-3 had a specific gravimetric capacitances of 361.3 and 392.7 F/g at a scan rate of 0.5 mV/s, respectively. A supercapacitor based on OAC-3 possessed a better power performance than that based on AC-4.