Substrate effect on structural and electrochemical properties of LiFePO_4 thin films grown by pulsed laser deposition

摘要

LiFePO_4 thin films are grown by pulsed laser deposition technique in relation to deposition parameters. Different characterizations such as XRD, SEM, Raman, and electrochemical studies are undertaken on the prepared samples. Structural phase of the deposited thin film expresses the orthorhombic Pnma olivine. LiFePO_4 thin films grown on Pyrex glass substrate have harsh surface with a few dispatches of grains, whereas the thin films deposited on ITO-coated glass substrate have demonstrated exceptionally fine and uniform particles without dispatches of grains. Raman peaks are situated at 1237.7 and 1416 cm~(-1). From the conductivity studies, the conductivity has been raised for the Pyrex glass up to 1.1 × 10~4 S cm~(-1) at 373 K, whereas in case of ITO-coated glass, the conductivity has been enhanced up to 1.6 × 10~4 S cm~(-1) at 373 K. The transmission spectra change CC from obscurity state to free state from 15 to 83% at around 39 cm~2 C~(-1). CV of LiFePO_4 thin film on ITO-coated glass substrate has exhibited the anodic and cathodic peaks at 3.2 and 3.19 V. These outcomes demonstrate that the determination of a suitable substrate is significant for creating the film terminal with the high rate limit, particularly in considering the utilization of microbatteries.