Microstructural and electrochemical properties of rf-sputtered LiFePO4 thin films

LiFePO4 has been synthesized by hydrothermal synthesis. A 2-in. sputtering target has been prepared using synthesized powder and employed for the deposition of LiFePO4 films by radio frequency magnetron sputtering. Microstructural properties have been studied by using X-ray diffraction, Raman spectroscopy, and atomic force microscope. The films deposited at 350 A degrees C with subsequent annealing at 600 A degrees C for 4 h exhibited well-crystallized peaks along with (101) predominant orientation which corresponds to orthorhombic olivine-type structure with Pnma space group. The electrochemical properties have been studied for films in aqueous as well as in non-aqueous media. Both the electrochemical cells at same current density of 20 mu A/cm(2) delivered the same initial discharge capacity around 38 mu Ah/cm(2) mu m. The Li//LiFePO4 cell exhibited good cycling stability for the first 20 cycles.