Hou Jingrong, Hadouchi Mohammed, Sui Lijun, Liu Jie, Tang Mingxue, Hu Zhiwei, Lin Hong-Ji, Kuo Chang-Yang, Chen Chien-Te, Pao Chih-Wen, Huang Yunhui, Ma Jiwei
Shanghai Key Laboratory for R&D and Application of Metallic Functional Materials, Institute of New Energy for Vehicles, School of Materials Science and Engineering, Tongji University, Shanghai, 201804, China.
Laboratoire de Chimie Appliquée des Matériaux, Centre des Sciences des Matériaux, Faculty of Science, Mohammed V University in Rabat, Avenue Ibn Battouta, Rabat, BP 1014, Morocco.
Small. 2023 Nov;19(46):e2302726. doi: 10.1002/smll.202302726. Epub 2023 Jul 21.
The rational design of novel high-performance cathode materials for sodium-ion batteries is a challenge for the development of the renewable energy sector. Here, a new sodium-deficient NASICON phosphate, namely Na □ Co Fe V(PO ) , demonstrating the excellent electrochemical performance is reported. The presence of Co allows a third Na to participate in the reaction thus exhibiting a high reversible capacity of ≈155 mAh g in the voltage range of 2.0-4.0 V versus Na /Na with a reversible single-phase mechanism and a small volume shrinkage of ≈5.97% at 4.0 V. Na solid-state nuclear magnetic resonance (NMR) combined with ex situ X-ray diffraction (XRD) refinements provide evidence for a preferential Na insertion within the Na2 site. Furthermore, the enhanced sodium kinetics ascribed to Co-substitution is also confirmed in combination with electrochemical impedance spectroscopy (EIS), galvanostatic intermittent titration technique (GITT), and theoretical calculation.
设计新型高性能钠离子电池阴极材料是可再生能源领域发展面临的一项挑战。在此，报道了一种新型缺钠NASICON磷酸盐，即Na□CoFeV(PO)，其展现出优异的电化学性能。Co的存在使得第三个Na能够参与反应，因此在相对于Na+/Na的2.0 - 4.0 V电压范围内表现出约155 mAh g的高可逆容量，具有可逆单相机制，且在4.0 V时体积收缩约5.97%。Na固态核磁共振（NMR）结合非原位X射线衍射（XRD）精修提供了Na优先插入Na2位点的证据。此外，结合电化学阻抗谱（EIS）、恒电流间歇滴定技术（GITT）和理论计算，也证实了由于Co取代而增强的钠动力学。
