对苯二甲酸锂负极材料的溶剂热法合成

Solvothermal synthesis of terephthalate lithium as negative materials

采用溶剂热法制备了对苯二甲酸锂(tpaLi2)配位聚合物锂离子电池负极材料,并用傅里叶红外光谱分析(FTIR)、X射线粉末衍射(XRD)、X射线单晶衍射、扫描电镜(SEM)和恒电流充放电测试对其结构、形貌和充放电性能进行了表征。结果表明:材料属于单斜晶系,P2(1)/c空间群,具有三维孔洞的配位聚合物框架结构,平均粒径在7～8μm。首次充电和放电比容量分别为98、180 mAh/g,循环40次后充放电容量分别为67、68 mAh/g。通过对比实验,分析了合成方法对性能的影响,提出了改进电化学性能的途径。

The terephthalate lithium （tpaLi2） coordination polymer as negative material was synthesized by solvothermal method. The samples were characterized by FTIR absorption spectra （FTIR）, X-ray diffraction （XRD）, X-ray single crystal diffraction, scanning electron microscope （SEM） and constant current charge-discharge experiment. The results show tpaLi2 is a 3D coordination polymer with micropores crystallized in monoclinic crystal system, P2（1 ）/c space group. The size of single grain is about 7-8 i^m. The initial charge and discharge capacities of this sample are 98, 180 mAh/g, respectively, and after 40 cycles the charge and discharge specific capacities remain 67 and 68 mAh/g. The impact on the performance of synthesis methods was analyzed through the contrast experiment, and the way of improving the electrochemical properties was put forward.