Alternative route for LiFePO4 synthesis: Carbothermal reduction combined with microwave-assisted solid-state reaction

Abstract

LiFePO4 was synthesized via a microwave-assisted solid-state reaction. The precursors LiOH·H2O, FePO4·4H2O, glucose, and graphite were first subjected to carbothermal reduction at 200°C during 3h and subsequently calcined under microwave irradiation at 800W for very short times varying from 1 to 5min. The products obtained at different microwave calcination times were systematically investigated through thermal (TGA-DTG and DSC), structural (XRD), morphological (SEM), and electrochemical (cyclic voltammetry) analyses. The best results were attained for the product obtained at the microwave calcination time of 3min: smallest particle size (majority in the range of 100–150nm), crystallographic pattern of LiFePO4 and some by-products, and voltammetric profile characteristic of LiFePO4. Thus, the here-presented synthesis methodology implies a significant reduction in processing time while yielding LiFePO4 nanoparticles with good electrochemical activity for the Li ion intercalation process.