Enhanced ethanol-sensing characteristics of Au decorated In-doped SnO2 porous nanotubes at low working temperature

In this work, Au decorated In-doped SnO2 (Au@In2O3-SnO2) porous nanotubes (PNTs) were fabricated via electrospinning and a subsequent calcination treatment. The In-doped SnO2 PNTs with various Au/Sn molar ratios possessed good ethanol sensing properties. As a result, the 3 % mol Au decorated In-doped SnO2 PNTs had high response to ethanol (Ra/Rg = 316.8–100 ppm) and can detect ethanol down to 50 ppb at a low working temperature of 150 °C. In addition, the gas sensor also had high selectivity, good reversibility and long-term stability. The enhanced sensing performance was mainly ascribed to the increase of oxygen vacancies, catalytic activity of Au nanocatalysts, and porous structures. The sensing results demonstrated that Au@In2O3-SnO2 PNTs had the great potential for ethanol detecting, and provide a facile method for rationally designing other types of gas sensors. •The Au decorated In-doped SnO2 porous nanotubes are easily to fabricate using electrospinning.•The 3 % Au@In2O3-SnO2 PNTs had high response to ethanol (Ra/Rg = 316.8–100 ppm) at 150 °C.•The gas sensor also had high selectivity, good reversibility and long-term stability.