A phase-transfer assisted solvo-thermal strategy for low-temperature synthesis of Na3(VO1−xPO4)2F1+2x cathodes for sodium-ion batteries

A series of Na₃(VO_1−xPO₄)₂F_1+2x (x = 0, 0.5 and 1) compounds with superior Na storage performance can be synthesized by a phase-transfer assisted solvo-thermal strategy at a rather low temperature (120 °C) in one simple step.