多孔碳钠电池负极材料制备及电化学性能研究

On Multiporous Sodium Carbon Battery Cathode Materials Preparation and Its Electrochemical Characteristics

采用高温热解法锻烧玉米芯成功合成了多孔碳并作为钠离子电池负极材料,对产物进行形貌、晶型及电化学性能测试。SEM分析显示,多孔碳粒径不均匀,呈介孔、微孔和大孔共存状态;XRD结果显示,多孔碳呈不定型结构,结晶度较低;电化学性能测试表明电极材料在第1,5,10,20,30次充放电循环时,其充放电比容量分别为550m Ahg^(-1)和700m Ahg^(-1),595m Ahg^(-1)和675m Ahg^(-1),440m Ahg^(-1)和465m Ahg^(-1),420m Ahg^(-1)和440m Ahg^(-1),405m Ahg^(-1)和410m Ahg^(-1)。经过30次充放电循环后其充放电比容量仍然比石墨(372m Ahg^(-1))要高,说明碳的多孔结构有利于钠离子扩散和电子传输,同时多孔具有高比表面积有利于电极材料与电解液的充分接触,有利于钠离子的脱嵌。

In this paper,multiporous carbon materials as the anode materials for sodium ion battery was successfully synthesized by using high temperature thermal decomposition method to burning wastes as corncob. The product morphology,crystal and electrochemical performance were tested. SEM analysis showed that particle sizes of multiporous carbon were not uniform. Mesoporous,microporous and macroporous states were coexisted. XRD results showed that the multiporous carbon was in amorphous state with the low degree of crystallinity. Electrochemical performance test showed that the charge and discharge specific capacity of the multiporous carbon electrode material in the 1st, 5th,10 th,20th,30 th cycle were 550 m Ahg^-1and700 m Ahg^-1,595 m Ahg^-1and 675 m Ahg^-1,440 m Ahg^-1and 465 m Ahg^-1,420 m Ahg^-1and 440 m Ahg^-1,405 m Ahg^-1and 410 m Ahg^-1,respectively. The special capacity after 30 cycles are still higher than that of graphite（ 372 m Ahg^-1）,thus proved that the multiporous structure of carbon was benefit to sodium ion diffusion and electronic transmission,and its high specific surface area was conducive to electrode materials fully contact with the electrolyte,which was also advantage to take off and inset of sodium ions.