Sintering Temperature Induced Evolution of Microstructures and Enhanced Electrochemical Performances: Sol-Gel Derived LiFe(MoO4)2 Microcrystals as a Promising Anode Material for Lithium-Ion Batteries

A facile sol-gel process was used for synthesis of LiFe(MoO4)(2) microcrystals. The effects of sintering temperature on the microstructures and electrochemical performances of the as-synthesized samples were systematically investigated through XRD, SEM and electrochemical performance characterization. When sintered at 650 degrees C, the obtained LiFe(MoO4)(2) microcrystals show regular shape and uniform size distribution with mean size of 1-2 mu m. At the lower temperature (600 degrees C), the obtained LiFe(MoO4)(2) microcrystals possess relative inferior crystallinity, irregular morphology and vague grain boundary. At the higher temperatures (680 and 700 degrees C), the obtained LiFe(MoO4)(2) microcrystals are larger and thicker particles. The electrochemical results demonstrate that the optimized LiFe(MoO4)(2) microcrystals (650 degrees C) can deliver a high discharge specific capacity of 925 mAh g(-1) even at a current rate of 1C (1,050 mA g(-1)) after 500 cycles. Our work can provide a good guidance for the controllable synthesis of other transition metal NASICON-type electrode materials.