采用填埋法将玉米芯进行炭化，炭化物经过脱灰处理后在碱炭比为4：1、温度为850℃的条件下进行活化，制备得到玉米基活性炭（CAC）。CAC经过深度脱灰制备得到CAC-T，CAC-T的比表面积从脱灰前的3 250 m²/g增加到3 487 m²/g。采用循环伏安、交流阻抗和恒流充放电对CAC、CAC-T的电化学性能进行测试，结果表明，CAC-T在电流密度为1 A/g时的单电极比容量为256.1 F/g，10 000次充放电后容量仍保持在255.8 F/g，容量保持率高达99.9%。

Corncob is carbonized by landfill method,and ash removal is performed for the carbonized products.Corncob-based activated carbon (CAC) is prepared under the conditions that the ratio of KOH to corncob-based carbon after removing ash is 4,and the activation temperature is at 850℃.CAC-T is obtained from CAC through deeply deashing.The specific surface area of CAC-T increases to 3 487 m²·g^-1 from the 3 250 m²·g^-1 of CAC.The electrochemical performances of CAC and CAC-T are tested with cyclic voltammetry (CV),electrochemical impedance spectroscopy (EIS) and galvanostatic charge-discharge.The results show that the specific capacitance of single CAC-T electrode is about 256.1 F·g^-1 at a charge-discharge current density of 1 A·g^-1.After 10 000 charge-discharge cycles,the specific capacitance of CAC-T electrode maintains at around 255.8 F·g^-1.The capacitance retention is as high as 99.9%.