The existence form and synergistic effect of P in improving the structural stability and electrochemical performance of Li_(2)Mn_(0.5)Fe_(0.5)SiO_(4)/C cathode materials

作     者：Lei Wei Shi-Xi Zhao Xia Wu Shu-Jin Zhao Ce-Wen Nan 

作者机构：Graduate School at ShenzhenTsinghua UniversityShenzhen518055China School of Materials Science and EngineeringTsinghua UniversityBeijing100084China School of Materials Science and EngineeringJiamusi UniversityJiamusi154007China 

出 版 物：《Journal of Materiomics》 (无机材料学学报（英文）)

年 卷 期：2018年第4卷第3期

页      面：179-186页

核心收录：

学科分类：0808[工学-电气工程] 0809[工学-电子科学与技术（可授工学、理学学位）] 07[理学] 0817[工学-化学工程与技术] 0806[工学-冶金工程] 0805[工学-材料科学与工程（可授工学、理学学位）] 0703[理学-化学] 0701[理学-数学] 0702[理学-物理学] 070101[理学-基础数学] 

基　　金：This work was supported by the National Natural Science Foundation of China(No.51372136) the NSFC-Guangdong united fund(U1401246) 

主　　题：Lithium-ion batteries Cathode material Li_(2)Mn_(0.5)Fe_(0.5)SiO_(4)/C P-doping Synergistic effect Structural stability 

摘      要：Nano-Li_(2)Mn_(0.5)Fe_(0.5)SiO_(4)/C cathode material is synthesized by a hydrothermal route and phosphorus substitution is applied to improve structural stability and electrochemical *** low substitution content,P element completely enters into the lattice,forms[PO_(4)]tetrahedrons and partially replaces[SiO_(4)]tetrahedrons,which is confirmed by X-ray diffraction and X-ray photoelectron spectroscope *** substitution helps to suppress the change of coordination number of Mn and stabilize the material structure to some extent,obtaining better electrochemical performance in the early *** the increase of P content,parts of P element exist in Li_(3)PO_(4)which distributes uniformly and co-exists with active *** tests prove that existing Li_(3)PO_(4)has positive impacts on cycle and rate performance,and the lithium ion diffusion coefficient increases by about 14 times than pristine *** the synergistic effects of phosphate substation and proper Li_(3)PO_(4),Li_(2)Mn_(0.5)Fe_(0.5)SiO_(4)/C shows enhanced electrochemical performances.