Epichlorohydrin (ECH) is mainly an industrial raw material, while it is toxic and dangerous for human health, so finding a simple and effective method for detecting ECH gas is challenging work. Porous SnO2 structures are successfully obtained through a hydrothermal method using SnCl4·5H2O as the tin source and water as the solvent. Ag nanoparticle (NPs) decorated porous SnO2 structures have also been prepared by the impregnation method. The morphology and structure of the as-prepared products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and the nitrogen adsorption–desorption technique. The as-synthesized nanostructures, with diameters ranging from 4–5 μm, are composed of porous nanosheets with an average thickness of 60 nm. The gas sensing properties of the Ag NPs decorated porous SnO2 structures for ECH gas were investigated in detail, and the results showed that the 10% Ag NPs decorated porous SnO2 structures gas sensor was the optimum sensor, demonstrating a response (S = 50) for 100 ppm of ECH gas, while the working temperature was decreased by about 180 °C. In addition, it showed a low detection level (0.5 ppm) for ECH gas, good reproducibility and repeatability, and long-term stability, implying a promising application in detecting ECH gas.

One-dimensional CdS@TiO2 core-shell heterostructures were fabricated via the hydrolysis of tetrabutyl titanate (TBT) on preformed CdS nanowires. The as-prepared products were characterized by X-ray diffraction, transmission electron microscopy, selected area electron diffraction and diffuse reflectance spectroscopy techniques. Results demonstrated that the hydrolysis of TBT had a great influence on the morphology of the coated TiO2 shell, resulting in the formation of TiO2 nanoparticles and nanolayer-modified CdS@TiO2 heterostructures. Degradation of methylene blue using CdS@TiO2 core-shell heterostructures as photocatalysts under visible light irradiation was investigated. Comparative photocatalytic tests showed that the TiO2 nanoparticles-modified heterostructure exhibited a superior activity due to the passivity of photogenerated charge carriers.