Interfacial oxidation–dehydration induced formation of porous SnO2 hollow nanospheres and their gas sensing properties

Uniform porous SnO2 hollow nanospheres with average diameters of about 100–200 nm have been reproducibly synthesized via a facile template- and surfactant-free hydrothermal method, using hydrogen peroxide 30% and stannous sulfate as precursors. The morphology, composition and structure of the resultant products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy and nitrogen adsorption–desorption technique. Experimental results demonstrated that the formation of these porous SnO2 nanostructures is ascribed to an interfacial oxidation–dehydration mechanism. H2O2 usage has an important effect on both the morphology and purity of the final products. The gas sensing properties of the as-prepared porous SnO2 hollow nanospheres were investigated. By comparative gas sensing tests, the porous SnO2 hollow nanospheres exhibited superior gas sensing performances over commercial SnO2 nanopowders toward some typical volatile organic compounds (VOCs), implying their promising applications in gas sensors.