Microstructural and Electrochemical Properties of rf-Sputtered LiFeO₂Thin Films

Abstract

Lithium iron oxide (LiFeO 2 ) thin films have been deposited by rf-magnetron sputtering technique and microstructural and electrochemical properties were studied. The films deposited at a substrate temperature 250°C with subsequent post annealing at 500°C for 4 h exhibited cubic rock-salt structure with Fm3m space group. The films exhibited well-defined oxidation and reduction peaks suggesting complete reversibility upon cycling. The as-deposited films exhibited an initial discharge capacity 15 μAh/cm 2 ·μm, whereas the films post annealed at 500°C for 4 h in controlled oxygen environment exhibited 31 μAh/cm 2 ·μm.