Enhanced acetone sensing properties based onin situgrowth SnO2nanotube arrays.

Large-scale and well-alignedin situgrowth SnO2nanotube (NT) arrays have been synthesized directly on the surface of the Al2O3ceramic tube by a cost-effective template self-etching method. The morphology ofin situSnO2NTs can be adjusted by changing the concentration of urea. The structure and morphology characteristics of SnO2NT were examined via x-ray diffraction, BET, and scanning electron microscopy, respectively. A series of detections were carried out to evaluate the gas sensing performances. The results indicated thatin situgrowth SnO2NT arrays sensor exhibited an excellent response (S = 20.3), good linearity under the concentration range of ppm level (5-300 ppm), and outstanding selectivity to 100 ppm of acetone gas. Compared with the sensors fabricated by a slurry-coating method, the controllablein situassembled SnO2NT arrays exhibited a more stable structure and easier fabrication process. The high acetone sensing performance might due to the unique hollow structure and favorable orientation growth. The dominant sensing mechanism about thein situgrowth SnO2NT arrays sensor has been discussed in detail. It is expected thatin situgrowth SnO2NT arrays sensor with the general working principle and controllable growth strategy will become a promising functional material in monitoring and detecting acetone.