Unraveling the reaction mechanism of high reversible capacity CuP_(2)/C anode with native oxidation PO_(x) component for sodium-ion batteries  

作　　者：Huixin Chen Chen Zhao Hongjun Yue Guiming Zhong Xiang Han Liang Yin Ding Chen 

机构地区：[1]State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body,College of Mechanical and Vehicle Engineering,Hunan University,Changsha 410082,China [2]CAS key Laboratory of Design and Assembly of Functional Nanostructures,and Fujian Provincial Key Laboratory of Nanomaterials,Fujian Institute of Research on the Structure of Matter,Chinese Academy of Sciences,Fuzhou 350002,China [3]College of Materials Science and Engineering,Co-Innovation Center of Efficient Processing and Utilization of Forest Resources,Nanjing Forestry University,Nanjing 210037,China [4]Laboratory of Advanced Spectro-electrochemistry and Li-ion Batteries,Dalian Institute of Chemical Physics,Chinese Academy of Sciences,Dalian 116023,China [5]Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China [6]Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials,Xiamen Institute of Rare Earth Materials,Haixi institutes,Chinese Academy of Sciences,Xiamen 361021,China

出　　处：《Chinese Chemical Letters》2025年第1期574-578,共5页中国化学快报(英文版)

基　　金：financially supported by National Nature Science Foundation of China(Nos.21805278,22272175 and 22209075);the Fujian Science and Technology Planning Projects of China(Nos.2022T3067 and 2023H0045);the Self-deployment Project Research Programs of Haixi Institutes,Chinese Academy of Sciences(No.CXZX-2022-JQ12);the Self-deployment project of XIREM(No.2023GG02)。

摘　　要：Phosphorus-based anode is a promising anode for sodium-ion batteries(SIBs)due to its high specific capacity,however,suffers from poor electronic conductivity and unfavorable electrochemical reversibility.Incorporating metals such as copper(Cu)into phosphorus has been demonstrated to not only improve the electronic conductivity but also accommodate the volume change during cycling,yet the underline sodiation mechanism is not clear.Herein,take a copper phosphide and reduced graphene oxide(CuP_(2)/C)composite as an example,which delivers a high reversible capacity of>900 mAh/g.Interestingly,it is revealed that the native oxidation PO_(x)components of the CuP_(2)/C composite show higher electrochemical reversibility than the bulk Cu P_(2),based on a quantitative analysis of high-resolution solid-state^(31)P NMR,ex-situ XPS and synchrotron X-ray diffraction characterization techniques.The sodiation products Na_(3)PO_(4) and Na_(4)P_(2)O_(7) derived from PO_(x) could react with Na-P alloys and regenerate to PO_(x) during charge process,which probably accounts for the high reversible capacity of the Cu P_(2)/C anode.The findings also illustrate that the phosphorus transforms into nanocrystalline Na_(3)P and Na_(x)P alloys,which laterally shows crystallization-amorphization evolution process during cycling.

关 键 词：CuP_(2)/C composite POx component Reaction mechanism Solid-state NMR Sodium-ion batteries 

分 类 号：TG1[金属学及工艺—金属学]