Indium Hydroxide and Indium Oxide Nanospheres, Nanoflowers, Microcubes, and Nanorods: Synthesis and Optical Properties

This paper reports the facile synthesis of indium hydroxide nanospheres, nanoflowers, microcubes, and nanorods using a solvothermal method at 240 °C for 18 h in an ethanol solution of indium acetate with the directing surfactants of ethylenediamine, acetic acid, and oleic acid. After calcination of as-synthesized indium hydroxide products at 500 °C for 4 h, corresponding indium oxide nanostructures were also obtained with sizes and morphologies similar to the indium hydroxide products. The phase compositions and morphologies of the resulting samples were characterized by X-ray diffraction, Raman spectroscopy, scanning electron microscopy, transmission electron microscopy, and selected area electron diffraction. On the basis of our findings, we propose a surfactant-assisted self-assembly formation mechanism to account for their formation processes. Room temperature photoluminescence was further carried out on the indium oxide samples to investigate their optical properties.