Novel mixed cubic-rutile structured In2O3-TiO2 composite nanoparticles (InTiO CNPs): Structure, morphology, photoluminescence and photocatalytic activity

Novel In2O3-TiO2 composite nanoparticles (InTiO CNPs) were prepared by wet chemical and PVA assisted wet chemical methods. The Fourier transform infrared spectroscopy confirms the presence of InO and TiO bond. The X-ray diffraction patterns revealed the pure phase with mixed cubic-rutile structure. The obtained phase transforms from anatase to rutile when calcination temperature increases (above 500 °C) for virgin InTiO CNPs whereas only cubic structure with rutile phase observed for PVA assisted InTiO CNPs even at low temperatures (as-prepared sample). Scanning electron microscopy and Transmission electron microscopy images of virgin CNPs showed an irregular morphology with large grain/particle sizes whereas PVA assisted CNPs showed spherical shape core-shell structured morphology with uniform grain/particle sizes. Particle size was found to be 182.40 nm-192.52 nm for virgin CNPs whereas 28.35 nm-34.76 nm for PVA assisted CNPs. Photoluminescence spectra showed a broad visible emission (violet and blue) with a calculated band gap energy of 2.65 eV. The PVA assisted InTIO CNPs showed a photocatalytic activity against methyl orange even at low irradiations with a degradation rate of 87%. The observed results with uniform morphology, good emission (violet and blue) behaviour with indirect band gap energy and a good photo catalytic activity of the prepared InTiO CNPs could be used for visible emissive thin film based electronic-optoelectronics devices and as a photo catalyst for organic dye degradation.