百合生物质碳材料的制备及其电化学性能研究

Preparation and electrochemical performance of Lily bulbs-based porous carbon

以百合根茎为生物质碳源,通过一步KOH化学活化结合高温碳化方法制备了多级孔径结构的生物质碳材料(LBC),采用X-射线粉末衍射(XRD)、拉曼光谱(Raman)、氮气吸脱附(BET)、场发射扫描电镜(FE-SEM)等对材料结构进行了表征,用循环伏安、恒电流充放电、交流阻抗谱对其电化学性能进行了研究.结果表明,LBC材料具有疏松多孔的结构;三电极系统测试时在^(-1).0～0V(vs.SCE)电位窗口内、1 000mV·s^(-1)的扫速下循环伏安曲线仍能保持良好的矩形形状;在电流密度1A·g^(-1)时比电容为199F·g^(-1);当电流密度增至50A·g^(-1)时仍能保持其初始比电容的83%;当组装为对称性二电极器件结构,在工作电压扩展至1.2V时,比电容为34F·g^(-1),能量密度为6.8 Wh·kg^(-1),功率密度为600W·kg^(-1).以上结果表明通过一步法制备的百合基碳材料在超级电容器电极材料领域具有一定的应用潜力.

By a one-step carbonization and activation method,hierarchically porous carbon materials are prepared from Lily bulbs.The microstructures were characterized by XRD,Raman,BET,FE-SEM and capacitive properties are examined by cycle voltammetry(CV),galvanostatic charge-discharge(GCD)and electrochemical impedance spectroscopy(EIS).The electrochemical measurement indicates that the obtained Lily bulbs-based porous carbon(LBC)shows favorable energy storage features in terms of specific capacitance(119 F·g-1)with excellent rate capability(83%capacitance retention at 50 A·g-1)in the three-electrode configuration.The LBC-based symmetric supercapacitor achieves an operation voltage of 1.2 V and energy density of 6.8 Wh·kg-1 at a power density of 600 W·kg-1 in the aqueous 6 mol·L-1 KOH electrolyte.These results indicate that the LBC is a promising supercapacitor electrode material and has potential applications in future.