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活性炭作为一种电极材料广泛应用于商业超级电容器中.炭材料表面的氧官能团是影响超级电容器电容性能的重要因素之一.通过(NH4) 2S2O8温和的氧化过程在活性炭上引入氧官能团,并在不同温度下热处理样品来进一步除去氧官能团,同时又保留了活性炭原始的孔结构.结果 表明,在水系电解液中,含氧官能团,特别是羧基和羰基,不仅加强了电解液在电极中的扩散,而且通过引入赝电容来提高电容.在300℃惰性气氛热处理后可以增加电极材料的电容和倍率性能.然而,不适量的氧官能团会堵塞活性炭的孔,导致其电化学性能差.在有机电解液中,含氧官能团会降低电极材料的电容,但在700℃惰性气氛热处理后可以有效提升材料的电容.研究结果揭示了氧官能团与电化学性能之间的关系,对于设计实际应用中的高性能超级电容器至关重要.“,”Oxygen functional groups on a commercial activated carbon were modified by (NH4) 2 S2 O8 oxidation and subsequent annealing at different temperatures.The effects of the surface modification on the electrochemical performance as supercapacitor electrodes were investigated by XPS,FTIR,argon adsorption and electrochemical tests.Results indicate that the oxygen functional groups,especially carboxyl and carbonyl groups improved the wettability of the pore surfaces,increased the electrolyte diffusion rate into the electrode and increased the specific capacitance by an additional pseudo-capacitance in a 6 mol/L KOH aqueous electrolyte.An excess oxygen content blocked the pores,leading to poor electrochemical performance,but annealing at 300 ℃ in an inert at mosphere increased the specific capacitance and improved the rate performance in a 6 mol/L KOH aqueous electrolyte.In a 1 mol/L Et4NBF4/PC organic electrolyte,however,oxygen functional groups introduced by (NH4)2 S2Os oxidation reduced the specific capacitance and annealing at 700 ℃2 to reduce their content effectively increased the specific capacitance.