Hydrothermal synthesis of Ga-doped In2O3 nanostructure and its structural, optical and photocatalytic properties

In this work, pure and Ga-doped In2O3 nanostructures have been synthesized by facile template-free hydrothermal method. The structural, morphological and optical properties are characterized by using XRD, FT-IR, HR-SEM and TEM, EDS, XPS, UV-DRS, and PL techniques. X-ray diffraction analysis indicates a pure cubic phase while crystallite size decreases with Ga doping. HR-SEM and TEM observations reveal irregular-shaped and spindle-like nanostructures with enhanced crystallinity and reduction in particle size with Ga doping. XPS spectra reveal the oxidation state of Ga is +3. The energy band gap estimated by UV-vis DRS spectroscopy is found to increase slightly from 3.40 to 3.45 eV with Ga doping. Photoluminescence spectra display violet, blue and green emission peaks are observed during Ga doping concentrations. Photodegradation of Methylene blue dye under ultra violet light radiation is found to double with Ga doping; i.e. 48% for Ga- In2O3 compared to 22% for pure In2O3.