Effect of sintering temperature on structural and optical properties of indium(III) oxide nanoparticles prepared with Triton X-100 by hydrothermal method

摘要

Indium(III) hydroxide (In(OH)_3) powders prepared via Triton X-100 mediated hydrothermal method was sintered at different temperatures (400, 500 and 600 ℃) to yield indium(III) oxide nanoparticles (In_2O_3 NPs). Thermal studies of In(OH)_3 confirmed complete conversion to In_2O_3 around 400 ℃. Powder X-ray diffraction (XRD) pattern of sintered In_2O_3 nanoparticles revealed the formation of phase pure cubic In_2O_3. The crystallite size of In_2O_3 NPs was increased from 12 to 26 nm upon increasing the sintering temperature from 400 ℃ to 600 ℃, while the percentage crystallinity was increased up to 90% after sintering at 600 ℃. A red shift in the band gap energy was observed with increasing sintering temperature due to the larger size of sintered In_2O_3 NPs. Room temperature photoluminescence spectra of the indium oxide nanoparticles showed both near band and excitonic emission of In_2O_3 due to oxygen vacancies.