文摘
CeO<sub>2sub> decorated SnO<sub>2sub> hollow spheres were successfully synthesized via a two-step hydrothermal strategy. The morphology and structures of as-obtained CeO<sub>2sub>/SnO<sub>2sub> composites were analyzed by various kinds of techniques. The SnO<sub>2sub> hollow spheres with uniform size around 300 nm were self-assembled with SnO<sub>2sub> nanoparticles and were hollow with a diameter of about 100 nm. The CeO<sub>2sub> nanoparticles on the surface of SnO<sub>2sub> hollow spheres could be clearly observed. X-ray photoelectron spectroscopy results confirmed the existence of Ce<sup>3+sup> and the increased amount of both chemisorbed oxygen and oxygen vacancy after the CeO<sub>2sub> decorated. Compared with pure SnO<sub>2sub> hollow spheres, such composites revealed excellent enhanced sensing properties to ethanol. When the ethanol concentration was 100 ppm, the sensitivity of the CeO<sub>2sub>/SnO<sub>2sub> composites was 37, which was 2.65-times higher than that of the primary SnO<sub>2sub> hollow spheres. The sensing mechanism of the enhanced gas sensing properties was also discussed.