Hollow ZnO@SnO2-Pt Core-Shell Nanofibers for Ethanol Sensing

In this study, ZnO@SnO2-Pt core-shell nanofibers with a hollow structure have been prepared by coaxial electrospinning and heat treatment. The core-shell and hollow structures of nanofibers were confirmed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The Brunauer-Emmett-Teller (BET) specific surface area test shows that the specific surface area of ZnO@ SnO2-Pt core-shell nanofibers is larger than those of ZnO@SnO2 coreshell nanofibers and SnO2 nanofibers. The gas-sensing test result shows that the response to 100 ppm ethanol gas is 132.04 and the response time is 5 s at 200 degrees C for ZnO@SnO2-Pt core-shell nanofibers with 0.3 wt % Pt. Compared with those of ZnO@SnO2 core-shell nanofibers without Pt and pure SnO2 nanofibers, the optimum working temperature of ZnO@ SnO2-Pt core-shell nanofibers is reduced by 125 degrees C and the maximum response is increased by 70.9 and 367.7%. Furthermore, the gas-sensing mechanism is discussed in detail.