文献类型：期刊文献

英文题名：Mitigating Lattice Distortion of Na4Fe3(PO4)2P2O7 Cathodes at High Voltage for High-Capacity Na-Ion Batteries

作者：Zhou, Linlin[1];Yu, Haifeng[1];Li, Chenwei[2];Chen, Ling[1];Jiang, Hao[1,3]

机构：[1]East China Univ Sci & Technol, Key Lab Ultrafine Mat, Sch Mat Sci & Engn, Shanghai Engn Res Ctr Hierarch Nanomat,Minist Educ, Shanghai 200237, Peoples R China;[2]Wuxi Nano Energy Technol Co Ltd, Wuxi 214125, Jiangsu, Peoples R China;[3]Xinjiang Univ, Sch Chem Engn & Technol, State Key Lab Chem & Utilizat Carbon Based Energy, Urumqi 830046, Xinjiang, Peoples R China

年份：2025

卷号：13

期号：12

起止页码：4908

外文期刊名：ACS SUSTAINABLE CHEMISTRY & ENGINEERING

收录：;EI(收录号：20251218072224);WOS:【SCI-EXPANDED(收录号:WOS:001447032200001)】；

基金：This work was supported by the National Natural Science Foundation of China (U22A20429 and 22308103), the Program for Shanghai Pilot Program for Basic Research (22TQ1400100-13), and the Fundamental Research Funds for the Central Universities.

语种：英文

外文关键词：Na-ion batteries; high energy density; elementdoping; mixed pyrophosphate

摘要：The Na4Fe3(PO4)(2)P2O7 (NFPP) cathode exhibits great potential for low-cost, high-safety, and long-life Na-ion batteries, yet lattice distortion at a high voltage of >3.1 V easily causes irreversible Na-ion extraction/insertion in pentagonal pyramid position (Na4 site). Herein, we forecast the elemental doping site according to the deviation degree and then realize the successful occupation of Li ions in Na4 sites of NFPP. The density functional theory calculations and experimental results verify that the Li ions in Na4 sites are not involved in the de/sodiation process but effectively hinder the shift of Fe along the a-axis and the distortion of P2O7 dime with well-maintained Na-ion diffusion paths even under high operation voltages. Consequently, Li-doped NFPP delivers an ultrahigh initial charge capacity of 128.7 mAh g(-1) (theoretical value: 129 mAh g(-1)) with a Coulombic efficiency of 87.9%. It also exhibits a superior capacity retention of 95.7% after 150 times at 1C with a predictively long-term cycle life of 80% after 5589 h. The increase in energy density of Fe-based phosphate cathodes is reckoned to further accelerate their large-scale applications in energy storage systems