Investigation of Structural, Optical & Electrical properties of LiCoO₂ thin films Grown by Pulsed Laser Deposition.

To fulfill the increasing demand for clean and green power, energy storage systems have been shaped by high energy density materials. In this regard, polycrystalline LiCoO₂ thin film has been prepared at the deposition temperatures of 400°C, and 650°C, & 700°C by pulsed laser deposition (PLD) on quartz substrate at high and (97 mTorr) low oxygen pressure (9.7mtorr). The phase evolution and surface morphology have been studied using X-ray diffraction (XRD) and Scanning electron microscopy (SEM). XRD data confirm the correspondence to the trigonal crystal lattice with the R3m space group where the LiCoO₂ film grown at 9.7 mTorr shows a significant amount of Co₃O₄ formation. Raman spectroscopy has been used to obtain information about the structural fingerprint of the prepared films by identifying the vibrational modes and it confirms the XRD analysis. UV-VIS reveals that samples grown at higher oxygen pressure has lower bandgap (2.23 eV) of about 2.24 % than the films grown at lower oxygen pressure (2.28) and electrical characteristics (conductivity measurement) demonstrate that films grown at high oxygen pressure are more electrically conductive. These findings imply that LiCoO₂ films produced by PLD hold promise for use in the production of solid-state batteries, and semiconductors.