Pulsed laser–deposited Li₂TiO₃ thin film electrodes for energy storage

Li₂TiO₃ (LTO) is a promising Ti-based material showing interesting electrochemical performance, good structural stability, cost-effectiveness, and non-toxic electrode material for energy storage and conversion. In this work, thin films of LTO have been deposited by the pulsed laser deposition (PLD) technique on Au/Ti/SiO₂/textured Si multilayer substrates maintained at different temperatures (T_s) in a partial pressure of 0.4 mPa, and the microstructural properties are investigated. The as-deposited films are textured and contain TiO₂ impurities. The LTO thin films grown at T_s of 600 °C are observed to be phase pure with a predominant (002) orientation related to the β-Li₂TiO₃ phase with C2/c symmetry. As electrodes for lithium microbatteries, LTO thin films delivered a specific discharge capacity of 46 μAh cm⁻² μm⁻¹ in the voltage range 0.0–1.0 V vs. Ag/AgCl and retained 91% capacity after 30 discharge cycles; as electrodes for supercapacitors, LTO thin films displayed a specific capacitance of 283 mF cm⁻² at a current density of 1 mA cm⁻² and retained 94% capacitance over 1000 cycles. The dual nature of the films demonstrates that the LTO films are suitable electrodes for supercapattery application.