OAM-RC

Abstract

LiCoO2 thin films were prepared by pulsed laser deposition technique. FTIR, Raman and Electrochemical measurements were made on to these films with respect to their deposition parameters i.e. substrate temperature (Ts), oxygen partial pressure (pO2) in the deposition chamber. The FTIR spectrum displayed the characteristic IR dominant bands at 250 and 554 cm –1 for LiCoO2 thin films deposited in pO2 = 200 mTorr. The Raman data consist of a series of broad bands located between 400 and 700 cm-1 for LiCoO2 films. The Raman band located at 592 cm-1 can be viewed as the symmetric Co-O stretching vibration of CoO6 groups. This band is assigned to the A1g symmetry in the D53d spectroscopic space group. Its broadening could be related with the cation-anion bond lengths and polyhedral distortion occurring in LiCoO2. The RS peak at 484 cm-1 derives from the Eg species. Electrochemical titration was made by charging and discharging the cells in the potential range between 2.0 and 4.2 V. Electrochemical potential spectroscopy (ECPS) was performed using 5 mV potential steps. Specific capacity 185 mC/cm2μm was measured for the film deposited in pO2 = 200 mTorr..

Keywords

LiCoO2, Thin films, PLD, FTIR, Raman, Electrochemical.

Citation

M. C. RAO, Synthesis and characterization of LiCoO2 thin film cathodes grown by pulsed laser deposition, Optoelectronics and Advanced Materials - Rapid Communications, 6, 3-4, March-April 2012, pp.511-515 (2012).

Submitted at: Feb. 2, 2012

Accepted at: April 11, 2012