Spectroscopic investigations on tetravalent doped LiCoO₂ thin film cathodes

¹ Department of Physics, Andhra Loyola College, Vijayawada 520 008, India
² Thin Film Laboratory, Department of Physics, Sri Venkateswara University, Tirupati 517 502, India

Corresponding author: raomc72@gmail.com

Received: 4 January 2009
Accepted: 8 June 2009
Published online: 17 September 2009

Abstract

Titanium-doped LiCoO₂ thin films were grown by pulsed laser deposition technique on silicon substrates. Structure, AFM, FTIR, Raman and Optical properties were studied with respect to their deposition parameters i.e. substrate temperature and oxygen partial pressure in the deposition chamber. The films deposited in  m Torr showed good crystallinity on silicon substrates maintained at  °C. It was found that such a film crystallizes in the layered α-NaFeO₂ structure. The influence of titanium doping on particle size and morphologies has been clearly studied. FTIR spectra displayed the characteristic IR dominant bands at 246 and 550 cm⁻¹ for titanium doped LiCoO₂ thin films. The Raman peaks observed for the films at 594 cm⁻¹ and 485 cm⁻¹ are ascribed to Raman active modes A_1g and E_g respectively. The influence of titanium doping on the physical properties has been systematically studied.