Continuous-flow rapid and controllable microfluidic synthesis of sodium vanadium fluorophosphate as a cathode material

Abstract

Sodium vanadium fluorophosphate (Na3V2O2(PO4)2F), which has a high theoretical capacity and operation voltage, is a promising cathode material for sodium ion batteries. However, its application is hindered by the expensive conventional synthetic methods, long synthesis time, and high synthesis temperature. In this study, we developed a microfluidics-based continuous-flow strategy for the rapid and controllable synthesis of ordered monodispersed Na3V2O2(PO4)2F nanospheres and nanosheets. Nanospheres were synthesized within a short reaction time of 6.3 s and exhibited an excellent rate capability of 114.0 mAh g − 1 at 10 C. Nanosheets exhibited outstanding cycle stability of 106.1 mAh g− 1 at 10 C and capacity retention of 97.3% after 1000 cycles. This work paves the way for low-cost, rapid, and large-scale preparation of electrode materials for rechargeable batteries.