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Phospho-olivine LiFePO 4 has been prepared using a facile hydrothermal method by optimizing the reaction temperatures.Structural and morphological properties of the as-prepared LiFePO 4 powders are systematically characterized using X-ray diffraction (XRD),scanning electron microscopy (SEM),transmission electron microscopy (TEM),infrared spectra,UV-vis spectra,and M ssbauer spectroscopy.It is demonstrated that the samples prepared in the temperature range from 160 to 200 ℃ crystallize in a single phase of phospho-olivine structure.All particles are rod-like,showing dimensions of approximately 150～200 nm in width and 500～600 nm in length with a preferential growth direction of [001].Within the lattice of LiFePO 4 rods,Fe 2+ ions partially disorderly occupy the Li + sites,which increases the cell volume.The electrochemical performance of LiFePO 4 is investigated by charge/discharge experiments.It is found that LiFePO 4 rods prepared at 200 ℃ deliver a specific discharge capacity of 147 mAh g-1,which is apparently superior to those prepared at lower reaction temperatures like 160 and 180 ℃.This observation is explained in terms of the thinner surface noncrystalline layer and lower level of Fe 2+ disorderly occupying the Li + sites.
Phospho-olivine LiFePO 4 has been prepared using a facile hydrothermal method by optimizing the reaction temperatures. Structural and morphological properties of the as-prepared LiFePO 4 powders are systematically characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) Transmission electron microscopy (TEM), infrared spectra, UV-vis spectra, and M ssbauer spectroscopy. It is characterized that the samples prepared in the temperature range from 160 to 200 ° C crystallize in a single phase of phospho-olivine structure. All particles are rod-like, showing dimensions of approximately 150-200 nm in width and 500-600 nm in length with a preferential growth direction of [001] .Within the lattice of LiFePO 4 rods, Fe 2+ ions disorder% occupy the Li + sites , these increases the cell volume. The electrochemical performance of LiFePO 4 is investigated by charge / discharge experiments. It is found that LiFePO 4 rods prepared at 200 ℃ deliver a specific discharge capacity of 147 mAh g-1, which is apparently superior to those prepared at lower reaction temperatures like 160 and 180 ° C. This observation is explained in terms of the thinner surface noncrystalline layer and lower level of Fe 2+ disorderly occupying the Li + sites.