Facile synthesis of hollow In2O3 microspheres and their gas sensing performances

Abstract

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 μm. 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 °C), and exhibited high response, low detection limit and excellent selectivity to NO₂.