甘氨酸基多孔碳/硒复合材料的制备及性能研究

Synthesis and Electrochemical Performances of Glycine-based Porous Carbon/Selenium Composite

以甘氨酸作为碳源,KOH为活化剂,通过直接碳化/活化,制备了氮掺杂的多孔碳材料。继与硒高温融混,制得多孔碳/硒复合材料。X-射线衍射和氮气吸脱附测试结果表明多孔碳主要呈无定型结构,并具有以微孔为主的多孔结构;硒则均匀地分散于多孔碳的微孔中。以其作为正极的锂硒电池,在电流密度为0.2C时,其首次可逆放电比容量为378.5 m Ah·g-1,经过100次循环,放电比容量仍可以保持在321 m Ah·g-1,表现出了良好的电化学性能。

The nitrogen doped porous carbon has been prepared by immediate carbonization/activation of glycine and KOH mixture. Subsequently,the porous carbon/selenium composite is obtained using melting diffusion route. XRD and N2 adsorption - desorption test show the porous carbon ＇with amorphous structure has primary microporous structure, and the element selenium is uniformly encapsulated into the microporous structure of carbon. As lithium ion battery cathode,the porous carbon/selenium delivers an initial reversible discharge capacity of 378.5 mA·g^-1,and a capacity value of 316.9 mAh·g^-1 can be retained after 100 cycles at a current density of 0.2C,proving the composite has a good cycling stability.