Enhanced ethanol sensing of SnO2 hollow micro/nanofibers fabricated by coaxial electrospinning

SnO2 hollow fibers with diameters ranging from 400 nm to 750 nm have been successfully fabricated by an efficient and facile approach of coaxial electrospinning. The XRD patterns demonstrate that the obtained SnO2 samples show a pure tetragonal rutile structure. The sensor based on the SnO2 micro/nanostructures exhibits excellent ethanol-sensing properties at a working temperature of 260 degrees C. It is exciting to observe that the tubular structure of the SnO2 hollow fibers significantly improves the gas-sensing sensitivity to ethanol compared to solid SnO2 fibers. The sensitivity of the SnO2 hollow fiber-based sensor towards 500 ppm ethanol is about 47.14, which is about 3 times higher than that of SnO2 fibers (14.89). It is pleasant to find that the SnO2 hollow fibers have a rapid response time (about 1 s). The good performance can be attributed to the enhanced effective surface area. These results depict a great potential for the use of micro/nano scale SnO2 hollow fibers for detecting ethanol.