Study On Gas Sensing Charateristics Of Zno-Sno2 Gas Sensor To H-2

One-dimensional (ID) semiconductor metal oxide nanostructures have attracted a great deal of attention in fields of electrochemistry, magnetic, optics, and gas sensors for their unique properties. As typical n-type metal oxides, SnO2 and ZnO have been well known for detecting inflammable or toxic gases. In this work, both ZnO-SnO2 nanoparticles and SnO2 nanoparticles were fabricated via hydrothermal synthesis. Microstructure characterization was performed using X-ray diffraction (XRD) and surface morphologies for the pure and doped samples were observed using field emission scanning electron microscope (FESEM), transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM). Then thin film gas sensors were made to study the gas sensing properties of ZnO-SnO2 and SnO2 nanostructures to H-2. A comparative study suggests more superior gas sensing performance for the sensor based on SnO2 and ZnO toward H-2 over that of the pure SnO2 nanoparticles. The enhanced gas sensing behaviors may be ascribed to the small size of grains and prominent electron transfer between the compound nanostructures and the absorbed oxygen species as well as to the heterojunctions of the ZnO nanoparticles to the SnO2 nanoparticles. The findings reveal the advantages of compound nanostructures which can effectively promote the functionality of gas sensors. Besides, this facile method could also be used to prepare many other sensing materials, which provides a new way to detect gases of interest depended on composite tin oxide nanoparticles.