RT Journal Article
T1 Sodium Rich Vanadium Oxy-Fluorophosphate – Na 3.2Ni0.2V1.8(PO4)2F2O – as Advanced Cathode for Sodium Ion Batteries
A1 Boulahya, Khalid
A1 Rachid Essehli, 
A1 Ben Yahia, Hamdi
A1 Amin, Ruhul
A1 Li, Mengya
A1 Morales, Daniel
A1 G. Greenbaum, Steven
A1 Abouimrane, Ali
A1 Parejiya, Anand
A1 Mahmoud, Abdelfattah
A1 Dixit, Mahmoud
A1 Belharouak, Mahmoud
AB Conventional sodium-based layered oxide cathodes are extremely air sensitive and possess poor electrochemical performance along with safety concerns when operating at high voltage. The polyanion phosphate, Na3V2(PO4)3 stands out as an excellent candidate due to its high nominal voltage, ambient air stability, and long cycle life. The caveat is that Na3V2(PO4)3 can only exhibit reversible capacities in the range of 100 mAh g−1, 20% below its theoretical capacity. Here, the synthesis and characterizations are reported for the first time of the sodium-rich vanadium oxyfluorophosphate, Na 3.2Ni0.2V1.8(PO4)2F2O, a tailored derivative compound of Na3V2(PO4)3, with extensive electrochemical and structural analyses. Na3.2Ni0.2V1.8(PO4)2F2O delivers an initial reversible capacity of 117 mAh g−1 between 2.5 and 4.5 V under the 1C rate at room temperature, with 85% capacity retention after 900 cycles. The cycling stability is further improved when the material is cycled at 50 °C within 2.8–4.3 V for 100 cycles. When paired with a presodiated hard carbon, Na3.2Ni0.2V1.8(PO4)2F2O cycled with a capacity retention of 85% after 500 cycles. Cosubstitution of the transition metal and fluorine in Na 3.2Ni0.2V1.8(PO4)2F2O as well as the sodium-rich structure are the major factors behind the improvement of specific capacity and cycling stability, which paves the way for this cathode in sodium-ion batteries.
PB Wiley-VCH GmbH
YR 2023
FD 2023-05-13
LK https://hdl.handle.net/20.500.14352/124334
UL https://hdl.handle.net/20.500.14352/124334
LA eng
NO Essehli, Rachid, et al. «Sodium Rich Vanadium Oxy‐Fluorophosphate – Na3.2 Ni0.2 V1.8 (PO4 )2 F2 O – as Advanced Cathode for Sodium Ion Batteries». Advanced Science, vol. 10, n.o 22, agosto de 2023, p. 2301091. DOI.org (Crossref), https://doi.org/10.1002/advs.202301091.
DS Docta Complutense
RD 31 dic 2025