Activated carbons were prepared from corncobs by an initial hydrothermal treatment using ammonium chloride as a pore forming additive and then by KOH activation. Samples were characterized by SEM, XRD, TG analysis and nitrogen adsorption. The effects of preparation conditions on the iodine number, yield and their electrochemical performance as supercapacitor electrodes were investigated. Results indicate that NH₄Cl is helpful for the formation of activated carbons with a hierarchical pore structure. The best activated carbon prepared has a good rate performance with a capacitance of 175 F·g⁻¹ at 0.5 A·g⁻¹ and a capacitance retention ratio of 73.0% at 20 A·g⁻¹, and a good cycling stability with a specific capacitance change from 175 to 173 F·g⁻¹ after a 10 000 charge/discharge test.

通过使用氯化铵作为成孔添加剂的初始水热处理，然后通过KOH活化，由玉米芯制备活性炭。通过SEM，XRD，TG分析和氮吸附对样品进行表征。研究了制备条件对碘值，得率及其作为超级电容器电极的电化学性能的影响。结果表明，NH ₄ Cl有助于形成具有分级孔结构的活性炭。制备的最佳活性炭具有良好的倍率性能，在0.5 A·g ^-1时的电容为175 F·g ^-1，在20 A·g ^-1时的电容保持率为73.0％并且，在10000次充放电试验后，比电容从175变化为173F·g ^-1，循环稳定性良好。