ZnCl2 salt as both molten medium and mineralizer in ambient pressure synthesis of metastable corundum-type In2O3 nanocrystals

At ambient pressure, metastable corundum-type In2O3 nanocrystals were successfully synthesized with ZnCl2 molten salt assisted calcination above 500 °C. The products were characterized by X-ray powder diffraction, transmission electron microscopy, scanning electron microscopy and photoluminescence spectroscopy. For the first time, we observed the formation of h-In2O3 with the aid of inorganic salt. The results show that ZnCl2 salt has significant effects on the formation of h-In2O3, which acted not only as a molten medium but also a mineralizer for the induced corundum phase. The approach requires neither complex apparatus and sophisticated procedures nor any organic additives during the reaction. The photoluminescence properties of In2O3 nanocrystals were also investigated.