Preparation of composite SnO2/CuO nanotubes by electrospinning and excellent gas selectivity to ethanol

Abstract

The composite SnO2/CuO nanotubes are prepared by uniaxial electrospinning. By controlling the molar ratio of tin to copper, SnO2/CuO nanotubes (F-1, molar ratio 1:1) and nanofibers (F-1, molar ratio 1:2) samples are prepared, respectively. The experimental results show that the composite SnO2/CuO nanotubes have excellent selectivity for ethanol, the response to ethanol at the same concentration and temperature is three times that of other gases, the saturated concentration of ethanol gas is 250 ppm and 300 ppm respectively, the optimal working temperature is 340 ℃ and the response value has a good linear relationship with the ethanol concentration between 25 and 300 ppm. The response value of F-1 is higher than that of F-2 in the same concentration of ethanol. The response value of the gas sensor based on F-1 to 250 ppm ethanol reaches 8.8 at 340 ℃, and its response and recovery time are 6 and 10 s respectively. The gas sensing mechanism of the material is explained by using the theory of electron depletion layer and barrier height, which is the basis of our follow-up work.