钠离子电池用石墨烯掺杂多孔材料的电化学性能

Electrochemical properties of porous materials doped with graphene for sodium ion battery

为了增加硬碳电极材料的导电性,选取石墨烯作为添加剂,采用涂覆法制备了石墨烯掺杂多孔材料,通过SEM、XRD、BET、蓝电电池测试系统和电化学工作站等对所得石墨烯多孔材料的结构和电化学性能进行表征和测试,探究不同碳化温度对于石墨烯掺杂多孔材料电化学性能的影响。结果表明:石墨烯掺杂多孔材料显示出均匀、丰富的孔结构和增强的石墨化程度,可降低接触电阻,缩短扩散距离,增强电子的传导性,用作电池负极时可有效提高钠离子电池的可逆比容量、倍率和循环性能;当碳化温度为1100℃时,所制备的石墨烯掺杂多孔材料电极表现出363.8 mA·h/g的高可逆比容量,在100 mA/g的电流密度下,循环300圈后,其可逆比容量基本无损失,表明该石墨烯掺杂多孔材料具有优异的电化学性能。

In order to increase the conductivity of the anode material for hard carbon,the graphene was selected as an additive,the graphene-doped porous material was produced by coating method.The prepared graphene-doped porous material was characterized by SEM,XRD and BET,and the electrochemical property was tested using electrochemical workstations and blue battery test systems.The effects of different carbonization temperature on electrochemical properties of the graphene-doped porous material were explored.The results show that the graphene-doped porous material has uniform and rich pore structure and enhanced graphitization degree,which can reduce contact resistance,shorten diffusion distance,and enhance electronic conductivity.When used as the battery cathode,they can effectively improve the reversible specific capacity,magnification and cycling performance of sodiumion battery.When the carbonization temperature is 1100℃,the prepared graphene-doped porous material electrode exhibites a high reversible specific capacity of 363.8 mA·h/g.After 300 cycles at current density of 100 mA/g,its reversible specific capacity has almost no loss,which indicating that the graphene-doped porous material electrode has excellent electrochemical properties.