文献类型：期刊文献

英文题名：Boosting the kinetic properties and suppressing the irreversible oxygen redox of lithium-rich manganese-based cathode materials through combined strategies of fast ionic conductor and oxygen vacancy

作者：Li, Heng[1];Cao, Shuang[1];Li, Zhi[1];Wu, Chao[1];Chen, Jiarui[1];Guo, Xiaowei[2];Chang, Baobao[3];Wang, Xianyou[1]

第一作者：Li, Heng

通讯作者：Wang, XY[1]

机构：[1]Xiangtan Univ, Natl Local Joint Engn Lab Key Mat New Energy Stora, Hunan Prov Key Lab Electrochem Energy Storage & Co, Natl Base Int Sci & Technol Cooperat,Sch Chem, Xiangtan 411105, Peoples R China;[2]Xinxiang Univ, Sch Chem & Mat Engn, Xinxiang 453003, Henan, Peoples R China;[3]Zhengzhou Univ, Key Lab Mat Proc & Mold, Minist Educ, Zhengzhou 450001, Henan, Peoples R China

第一机构：Xiangtan Univ, Natl Local Joint Engn Lab Key Mat New Energy Stora, Hunan Prov Key Lab Electrochem Energy Storage & Co, Natl Base Int Sci & Technol Cooperat,Sch Chem, Xiangtan 411105, Peoples R China

通讯机构：[1]corresponding author), Xiangtan Univ, Natl Local Joint Engn Lab Key Mat New Energy Stora, Hunan Prov Key Lab Electrochem Energy Storage & Co, Natl Base Int Sci & Technol Cooperat,Sch Chem, Xiangtan 411105, Peoples R China.

年份：2023

卷号：939

外文期刊名：JOURNAL OF ALLOYS AND COMPOUNDS

收录：;EI(收录号：20230313385589);Scopus(收录号：2-s2.0-85146191817);WOS:【SCI-EXPANDED(收录号:WOS:000921410800001)】；

基金：Acknowledgments This work was supported financially by the National Natural Science Foundation of China (No. U19A2018) , the Key Project of Strategic New Industry of Hunan Province (No. 2019GK2032) and Postgraduate Scientific Research Innovation Project of Hunan Province (No. CX20210635) . The authors are grateful to eceshi ( www.eceshi.com ) for the XPS test.

语种：英文

外文关键词：Lithium-rich manganese-based cathode materials; Irreversible anionic redox; Interfacial engineering; Fast ionic conductor; Oxygen vacancies

摘要：Oxygen-anion charge compensation facilitates lithium-rich manganese-based cathode materials (LRMCs) to possess higher specific capacity than other conventional layered oxide cathode materials. Nevertheless, irreversible oxygen redox makes LRMCs suffer from oxygen loss, structure degradation, and interfacial side reactions and thus resulting in low initial coulombic efficiency (ICE), poor cyclic stability and rate capacity. To inhibit the irreversible anionic redox and improve the kinetic properties of Li(1.2)Mn(0.54N)i(0.13)Co(0.13)O(2) (LMNCO), herein, an interfacial engineering with sodium hypophosphite (NaH2PO2) is used to modify the LMNCO. The results demonstrate that the Na2HPO4 and reducing gas PH3 that are produced by NaH2PO2 decomposition can react with the residual lithium and unstable surface oxygen to form a stable Li3PO4 protective layer and generate oxygen vacancies on the LMNCO surface. It has been found that the optimum content of NaH2PO2 is 5 wt%, and the electrochemical performance of LMNCO-NP 5% is significantly im-proved. The ICE of LMNCO-NP 5% is 82.79%, which is much higher than the LMNCO (73.76%). Meanwhile, the capacity retentions of LMNCO-NP 5% are 94.85% and 78.45% at 1 C and 5 C after 100 cycles, respectively. Therefore, the modification strategy based on the formation of Li3PO4 protective layer and generation of oxygen vacancies can play effectively promote the electrochemical performances of LMNCO. (c) 2023 Elsevier B.V. All rights reserved.