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 degrees 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. (C) 2011 Elsevier B.V. All rights reserved.