Ultrasensitive ethanol sensor based on 3D aloe-like SnO2

3D aloe-like SnO2 nanostructures were synthesized by a simple hydrothermal method. The scanning electron microscopy result indicated that this unique structure was assembled by leaf-like sheets, which consisted of large amount of small protrusive nanosheets with width of 5–10 nm. The sensor fabricated by aloe-like SnO2 nanostructures exhibited an excellent response and selectivity to ethanol. The developed sensor can detect ethanol as low as 50 ppb at 285 °C. The ultrasensitive ethanol detection was probably related to the less agglomerative and thinner structure of aloe-like SnO2. The modulation of the conductance of aloe-like SnO2 by the small nanosheets could also be considered to explain the ultrasensitive behavior to the low concentration of ethanol.