CoSe_(2)/Ti_(3)C_(2)T_(x)复合材料的制备及电化学性能研究  

Fabrication and Electrochemical Performances of CoSe_(2)/Ti_(3)C_(2)T_(x)Composites

作　　者：阎子豪 陈庆 骆丽杰[1] 李建保[1] 陈拥军[1] YAN Zihao;CHEN Qing;LUO Lijie;LI Jianbao;CHEN Yongjun(School of Materials Science and Engineering,State Key Laboratory of Marine Resource Utilization in South China Sea,Hainan University,Haikou 570228,Hainan,China)

机构地区：[1]海南大学材料科学与工程学院,南海海洋资源利用国家重点实验室,海南海口570228

出　　处：《陶瓷学报》2022年第6期1037-1045,共9页Journal of Ceramics

基　　金：国家自然科学基金(51702072)。

摘　　要：CoSe_(2)具有494.4 mAh·g^(-1)的高理论比容量,有望成为高功率锂离子电池的理想负极材料。然而,其实际容量会在循环过程中迅速下降。MXene系Ti_(3)C_(2)T_(x)材料尽管比容量低(110 mAh·g^(-1)),但具有出色的循环稳定性。因此,通过水热法将CoSe_(2)颗粒原位生长在Ti_(3)C_(2)T_(x)基底上,成功制备了一种新型CoSe_(2)/Ti_(3)C_(2)T_(x)复合材料作为锂离子电池负极,并显示出高比容量和良好的稳定性。通过X射线衍射(XRD)、扫描电子显微镜(SEM)和透射电子显微镜(TEM)对CoSe_(2)/Ti_(3)C_(2)T_(x)复合材料的组成、形貌和结构进行了表征,并研究了水热温度、水热时间对CoSe_(2)/Ti_(3)C_(2)T_(x)复合材料形貌和性能的影响。通过恒电流充放电、循环伏安测试(CV)和电化学阻抗(EIS)对CoSe_(2)/Ti_(3)C_(2)T_(x)复合材料的电化学性能进行测试。实验结果表明,当水热温度为200℃、水热时间为16 h时,CoSe_(2)/Ti_(3)C_(2)T_(x)复合材料在0.3 A·g^(-1)的电流密度下充放电循环1000次后,仍具有180.46 mAh·g^(-1)的较高比容量。CoSe_(2)has a high theoretical specific capacity of 494.4 mAh·g^(-1)and hence is expected to be a viable anode material for high-power lithium-ion batteries(LIBs).However,its actual capacity degrades rapidly during the cycling process.MXene Ti_(3)C_(2)T_(x)possesses excellent cycle stability though its specific capacity is relatively low(110 mAh·g^(-1)).A novel CoSe_(2)/Ti_(3)C_(2)T_(x)composite with high specific capacity and good stability was successfully prepared by growing CoSe_(2)particles in-situ on Ti_(3)C_(2)T_(x)by using hydrothermal method.The effects of hydrothermal temperature and time on morphology and specific capacity of the CoSe_(2)/Ti_(3)C_(2)T_(x)composite were studied.Phase composition,morphology and structure of the CoSe_(2)/Ti_(3)C_(2)T_(x)composite were characterized by X-using ray diffraction(XRD),scanning electron microscopy(SEM)and transmission electron microscopy(TEM).Electrochemical performances of the CoSe_(2)/Ti_(3)C_(2)T_(x)composite were examined by using galvanostatic charge-discharge,cyclic voltammetry(CV)and electrochemical impedance spectroscopy(EIS).When the hydrothermal temperature is 200℃and the holding time is 16 h,the CoSe_(2)/Ti_(3)C_(2)T_(x)composite as an anode for LIBs had specific capacity of 180.46 mAh·g^(-1)even after 1000 charge-discharge cycles at a current density of 0.3 A·g^(-1).

关 键 词：CoSe_(2) Ti_(3)C_(2)T_(x)MXene 锂离子电池 负极材料 电化学性能 

分 类 号：TQ174.75[化学工程—陶瓷工业]