为探究更绿色环保的三维还原氧化石墨烯的制备方法,采用简单易行的一步水热法,以Vc为绿色还原剂,L-天冬素为N源,在90 ℃下分别反应1、2、3、5、10 h,制得N掺杂的三维石墨烯水凝胶,经冷冻干燥得气凝胶;在三电极体系下对材料进行电化学测试,测试结果表明:在反应时间为3 h时,比电容值最高,在电流密度为1 A/g时,比电容值达173.8 F/g.且经过1 000次充放电循环后,比电容保持率为83%.且内阻较小(0.6 Ω),具有很好的功率性能和电容行为.
To explore more environmental friendly method of preparing three dimension reduced graphene oxide, herein, using L-Asparagine as nitrogen source and vitamin C as green reductant, we proposed a simple one step hydrothermal method. After reaction at 90 ℃ for 1,2,3,5,10 h and then freeze-drying, the three dimensional N doped graphene aerogel is prepared. And the test, conducted under three electrode system indicates that the material with 3 h reaction time shows better electrochemical performance, smaller internal resistance. The specific capacitance is 173.8 F/g at current density of 1 A/g. And after 1 000 times charge and discharge cycles, the specific capacitance remain at a rate of 83%. In addition,it has lower internal resistance(0.6 Ω). In summary, the material has excellent power performance and capacitance behavior.
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