Nanoporous In2O3 nanocrystal clusters:: One-step synthesis, thermal stability and optical property

Nanoporous In2O3 nanocrystal clusters with high surface areas have been synthesized by a one-step solvent-thermal method at a relatively low temperature. On the basis of our experimental data and nanomaterial growth mechanism, a template-assistant dehydration accompanied by aggregation mechanism was proposed to explain their formation. Besides, the influence of the high-temperature treatment on their porous structure and optical properties were studied and compared by various technologies. Little influence was found for their morphologies. It was intriguing to note that the initial In2O3 NCCs exhibited strong UV absorptions and near band emissions due to a quantum confinement effect of their subunits. However, after calcination, the weak confinement effect was retained in absorption spectra, a deep level emission arising from oxygen vacancies was observed in PL spectra.