Ultra-rapid microwave synthesis of triplite LiFeSO4F

Abstract

Quick, effective synthesis of the 4 V Li-ion battery cathode material, triplite LiFeSO₄F, takes place via facile conversion of the defect-peppered nanocrystalline tavorite precursor that forms on ultra-rapid microwave heating (10 min) of FeSO₄·H₂O/LiF. We propose a mechanism for its unique phase transformation to the triplite that occurs as a consequence of the disorder and hydroxyl defects induced by the fast nucleation. The electrochemical properties of the resultant triplite exhibits a doubling of its practical gravimetric capacity compared to the material prepared by conventional methods.