摘要：Activated carbon (AC) was modified by surfactants to enhance the electroadsorption property of an electrode. In this research, cetyltrimethyl ammonium bromide (CTAB) was selected as the best modifier from five common surfactants. We further studied the effects of the CTAB dosage, impregnation ratio of m(AC): w(HN〇 3), and impregnation time on the specific capacitance and coulombic efficiency of the electrode. The results showed that the optimum parameters of modification were 0.9 g for CTAB, 1:1.6 for m(AC): m(HN〇 3), and 23 h for impregnation time. The influence degrees on the specific capacitance follow the order of impregnation time > m(AC):m(HN〇 3) > CTAB dosage; the influence degrees on the coulombic efficiency follow the order of m(AC):m(HN〇 3) > impregnation time > CTAB dosage. The specific surface area of the modified AC is reduced from 930.095 m2 g-1 to 557.751 m2 g-1, but the surface hydrophilicity is significantly improved because the contact angle is reduced from 127° to 52°. In addition, hydrophilic functional groups, such as -NH3, -COOH, were found on the surface of the modified AC and are conducive to improving electroadsorption performance. The specific capacitance of the modified electrode increased by 45.11%, from 66.55 F g_1to 96.57 F g'1, and the coulombic efficiency increased from 56% to 83. 33%.
