Investigation on electronic and magnetic properties of Cr doped V2O5 thin films prepared by chemical solution deposition method

Abstract

The present study examines the role of Cr doping on the electronic and magnetic behaviour of V2O5i.e. V2-xCrxO5 (x = 0, 0.05, and 0.10) thin films, prepared by chemical-solution deposition technique on Si (111) substrate. X-Ray diffraction technique shows the purity of the films and confirms no secondary phase formation. The atomic force microscopy was used to confirm the roughness of the films. A morphological investigation is done using High-resolution scanning electron microscopy associated with Energy dispersive X-Ray mapping of each element of the film. Fourier transform Infrared spectroscopy is utilised to identify functional groups that are present in obtained samples. The band-gap of these obtained samples is in the range of 0.8–0.6 eV, as examined by UV–Vis i.e., its value is decreasing with Cr doping. Using vibrating sample magnetometer, it is clear that samples shows ferromagnetic (FM) behaviour with saturation magnetization 0.3–0.6 μB/cc consistent with Langevin function fitting. It concludes the presence of FM behaviour of films and magnetization increases with carrier density, consistent with the carrier-induced origin of the ferromagnetism. X-ray photoemission spectroscopy (XPS) is utilised to understand its electronic properties. Core level spectra measurements suggest that V is in mixed state of 5+ and 4+. However Cr is in 3+ states. XPS and UV–Vis measurements imply that oxygen vacancies significantly contribute to the declination of the band gap and the promotion of FM-like behaviour. This discovery offers a promising pathway for engineering novel devices.