Facile synthesis of hollow In2O3 microspheres and their gas sensing performances

Hollow In2O3 microspheres constructed by primary nanoparticles were successfully prepared by thermal treatment of the precursor, which was synthesized via a facile chemical solution route without any templates or surfactants. The images of field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) indicated that the sample was composed of a large number of hollow In2O3 microspheres with diameters of 1-2 mu m. In addition, a gas sensor based on the In2O3 hollow microspheres was fabricated and its gas sensing performances were investigated. It was found that sensors based on the as-prepared sample had a low operating temperature (80 degrees C), and exhibited high response, low detection limit and excellent selectivity to NO2.