In2O3 nanocrystals with a tunable size in the range of 4-10 nm:: One-step synthesis, characterization, and optical properties

Nearly monodispersed indium oxide (In2O3) nanocrystals with tunable sizes of < 10 nm were prepared by a one-pot solvothermal route using indium oleate as the precursor. The nanocrystals were characterized by transmission electron microscopy (TEM), high-resolution TEM, X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and thermogravimetric techniques. A kinetically controlled hydrolysis of indium oleate based on the water deficiency in the system was attributed to the time-dependent crystal growth, in which a heterogeneous nucleation and growth of new In2O3 onto the preformed nuclei were carried out. A weak quantum confinement effect of In2O3 nanoparticles resulting from the small crystal size was observed in UV spectra, and three photoluminescence emission peaks occurring in the visible region were detected as well.