Unlocking the Multi-Redox (Nb5+/Nb4+/Nb3+) Reactions in Nasicon- Nb2(PO4)3 Anode for Li- and Na-Ion Batteries

• DOI: 10.1149/ma2024-01113mtgabs
• Publication Date: 2024-08-19T15:07:37Z
• Authors: Biplab Patra; Keshav Kumar; Debolina Deb; Subham Ghosh; Sai Gautam Gopala...; Premkumar Sengutt...
• Keywords: Fast ion conductor; Formula unit

NASICON (Natrium Super-Ionic CONductor) type materials are known for their high structural, and thermal stability superior sodium ion mobility which make this framework an efficient electrode material Na-ion batteries. 1 In recent times NASICON-type compounds have been widely explored as Li- cathodes solid-state electrolytes but largely ignored anodes due to lower capacities higher intercalation voltages, reduce the overall energy densities of batteries (LIBs SIBs). structure has a general molecular formula Na x MM′(PO 4 ) 3 , where two MO 6 octahedra corners shared with three PO tetrahedra along c -direction resulting in “lantern units” each lantern unit joins six other units, generating large interstitial space that can accommodate up four alkali cations per unit. 2 family usually all members contain Na/Li ions terms synthesis electrochemical/chemical oxidation routes must be employed remove from parent compound. Herein, first time we will present comprehensive study on structural electrochemical properties empty (contains no Li or its pristine state) mixed valance Nb (PO potential application anode LIBs SIBs. Due multi-redox activity Nb, it is possible attain insertion capacity (~ 150 mAh g -1 SIBs ~ 170 LIBs) relatively voltages (1.8 V vs. + /Li 0 1.4 /Na compared Ti V-based anodes. 3,4 Our in-situ XRD measurements revealed multiple-phase transformations during formation short-range ordered triclinic ( P -1)-Na at end discharge. The distinct behavior ascribed relative differences size, filling crystallographic sites, chemical characters ions. density functional theory calculations also agreement predicting stable composition Na-Nb pseudo-binary system. X-ray absorption spectroscopy confirms participation 5+ /Nb 4+ 3+ couples. Although micron-sized showed moderate storage (~106 84 cells, respectively) 1C rate after 200 cycles, further optimization expected produce better performance. future, pairing suitable enable high-energy 5 References: C. Masquelier L. Croguennec, Chem. Rev. 113 6552–6591 (2013). Z. Jian, Y. Hu, X. Ji, W. Chen, Adv. Mater. 29 1601925 (2017). Y.S. Electrochem. commun. 14 86–89 (2012). Xu, Tang, Q. Wei, J. Meng, Haung, Zohu, G. Zhang, He, Mai, Nano Energy 28 224–231 (2016). B. Patra, K. Kumar, D. Deb, S. Ghosh, G.S. Gautam, P. Senguttuvan, A 11 8173–8183 (2023).