Enhancement of thermoelectrical performance in Au-ion implanted V2O5 thin films

Abstract

The present study reports an enhancement of thermoelectric performance in Au ion implanted V₂O₅ thin films. Structural studies reveal the formation of nanocrystalline Au clusters in the Au ion implanted V₂O₅ thin films and some reduction of V₂O₅ phase into VO₂ phase due to the defects created by Au ion implantation. The electrical resistivity (ρ) of thin films is decreased by about a factor of 4 upon Au ion implantation, but the magnitude of the Seebeck coefficient |S| decreases from 477.90 to 343.11 μV K⁻¹, and results in a significant increase of the power factor (PF). Engineering of the electronic density of states (DOS) and the energy filtering mechanism (EFM) are two different approaches that can improve the PF. However, a successful combination of these two methods is elusive. The present study demonstrates that the PF of Au implanted V₂O₅ thin films can be significantly promoted by both these effects. Simultaneous resonant distortions in DOS and EFM result in the enhancement in PF from 1.18 × 10⁻⁸ to 3.51 × 10⁻⁵. This study may pave a way to prepare high-performance oxide based thermoelectric devices.