Effect of Capping Agent on the Morphology, Size and Optical Properties of In2O3 Nanoparticles

The Indium Oxide (In2O3) nanoparticles were synthesized through Acacia gum mediated method with the surfactants CTAB (Cetyl Trimethyl Ammonium Bromide) and SDBS (Sodium Docecyl Benzene Sulfonate). The characterization of the synthesized In2O3 nanoparticles was carried out by XRD, FTIR, RAMAN, TEM, SEM, EDAX, UV-Vis and PL techniques. TG-DTA analysis was performed to know the calcination temperature of In2O3 nanoparticles. XRD analysis confirmed the crystalline nature of the synthesized In2O3 nanoparticles. The morphology and chemical composition were characterized by TEM, SEM and EDAX respectively. It was observed that morphology and size of synthesized nanoparticles measured by TEM and SEM analysis were dependent on the type of capping agent (surfactant) used. Raman and UV-Vis spectral analysis confirmed that the band gap value of CTAB capped In2O3 particles were larger than the SDBS capped In2O3 particles. FTIR analysis indicated that the bands were stretched in In2O3 particles capped by SDBS than by CTAB. From the photoluminescence studies (PL technique), a blue shift in the emission peaks of CTAB and SDBS capped In2O3 particles was observed that indicates larger optical band gap than the bulk.