Niobium oxyphosphate nanosheet assembled two-dimensional anode material for enhanced lithium storage  

作　　者：Bo Wen Ruiting Guo Xiong Liu Wen Luo Qiu He Chaojiang Niu Jiashen Meng Qi Li Yan Zhao Liqiang Mai 

机构地区：[1]State Key Laboratory of Advanced Technology for Materials Synthesis and Processing,Wuhan University of Technology,Wuhan 430070,Hubei,China [2]State Key Laboratory of Silicate Materials for Architectures,Wuhan University of Technology,Wuhan 430070,Hubei,China [3]Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory,Foshan 528216,Guangdong,China

出　　处：《Journal of Energy Chemistry》2021年第2期268-275,I0009,共9页能源化学（英文版）

基　　金：supported by the National Natural Science Foundation of China (21805219, 51832004, 51521001);the National Key Research and Development Program of China (2016YFA0202603);the Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory (XHT2020-003);the Programme of Introducing Talents of Discipline to Universities (B17034);the Yellow Crane Talent (Science & Technology) Program of Wuhan City。

摘　　要：The development of high-capacity and high-rate anodes has become an attractive endeavor for achieving high energy and power densities in lithium-ion batteries(LIBs).Herein,a new-type anode material of reduced graphene oxide(rGO) supported niobium oxyphosphate(NbOPO_4) nanosheet assembled twodimensional composite material(NbOPO_4/rGO) is firstly fabricated and presented as a promising highperformance LIB anode material.In-depth electrochemical analyses and in/ex situ characterizations reveal that the intercalation-conversion reaction takes place during the first discharge process,followed by the reversible redox process between amorphous NbPO_4 and Nb which contributes to the reversible capacity in the subsequent cycles.Meanwhile,the lithiation-generated Li3 PO_4,behaving as a good lithium ion conductor,facilitates ion transport.The rGO support further regulates the structural and electron/ion transfer properties of NbOPO_4/rGO composite compared to neat NbOPO_4, resulting in greatly enhanced electrochemical performances.As a result,NbOPO_4/rGO as a new-type LIB anode material achieves a high capacity of 502.5 mAh g^(-1) after 800 cycles and outstanding rate capability of 308.4 mAh g^(-1) at 8 A g^(-1).This work paves the way for the deep understanding and exploration of phosphate-ba sed high-efficiency anode materials for LIBs.

关 键 词：2D nanomaterials Niobium oxyphosphate High-rate anode Lithium storage mechanism Lithiation-induced amorphization 

分 类 号：TQ135.12[化学工程—无机化工] TB383.1[一般工业技术—材料科学与工程] TM912[电气工程—电力电子与电力传动]