SnO2 clusters embedded in TiO2 nanosheets: Heterostructures and gas sensing performance

SnO 2 clusters were embedded in superior thin TiO 2 nanosheets to form heterostructures via a two-step solvothermal synthesis . Superior thin TiO 2 (B) nanosheets were firstly prepared, in which these nanosheets exhibited homogeneously sheet structure without aggregation. After deposition of SnO 2 clusters, the mixture phase consisted of anatase and TiO 2 (B) was obtained even though the nanosheet morphology remained unchanged. The ratio of SnO 2 and TiO 2 was adjusted to get enhanced gas sensing performance. The gas sensing activity of samples for volatile organic compounds including acetone, ethanol and triethylamine was tested. Results indicates that SnO 2 /TiO 2 heterostructure with an optimal SnO 2 weight ratio of 10% is remarkably responsive to acetone, ethanol and triethylamine . Especially, the response time to triethylamine is only 10 s. In the case of 2 ppm, the sample still revealed a significant response to triethylamine. The enhanced sensing performance has to ascribed to the significant increase of reactive active sites by loading SnO 2 clusters. In addition, ultra-thin morphology and mixed phase composition of TiO 2 also enhance the property of the composite. This work supplied an idea for the preparation of SnO 2 based gas sensors.