Selective epichlorohydrin-sensing performance of Ag nanoparticles decorated porous SnO2 architectures

Abstract

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.