Preparation of In2O3 octahedrons by heating InCl3 aqueous solution on the Si substrate

In2O3 octahedrons have been synthesized by heating InCl3 aqueous solution on the Si substrate at 400–900 °C for 2 h. The average size of In2O3 octahedrons is decreased by increasing the heating temperature. The In2O3 octahedrons are single-crystalline with the body-centered cubic structure and have controllable sizes in the range of 0.7–1.0 μm. A possible mechanism was also proposed to account for the formation of In2O3 octahedrons. A strong photoluminescence with a peak at 458 nm was observed from the In2O3 octahedrons at room temperature. This emission can be attributed to oxygen vacancies and indium–oxygen vacancy centers.