Microwave-assisted synthesis of porous nano-sized Na3V2(PO)2F3@C nanospheres for sodium ion batteries with enhanced stability

Na3V2(PO4)(2)F-3 is a prospective cathode material for sodium ion batteries (SIBs) because of its high theoretical capacity. Nevertheless, its low electronic conductivity leads to poor cycling and rate performance, hindering its practical application. In this work, ultrafine-Na3V2(PO4)(2)F-3 nanocrystals less than 20 nm embedded in porous carbon nanospheres are fabricated via a microwave-assisted glycerol-mediated hydrothermal process followed by annealing. Microwave irradiation is shown to be critical for the formation of homogenous ultrafine nanostructure. The product exhibits a charge/discharge capacity of 106 mAh g(-1) at 0.5 C after 100 cycles with a retention of approximate 100% as cathode material for SIBs. (C) 2020 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.