A novel sensor for fast detection of triethylamine based on rutile TiO_2 nanorod arrays

摘要

A TiO_2 nanoparticle (TP) film is employed as a seed layer for the hydrothermal growth of single crystalline rutile TiO_2 nanorod arrays on the substrate. The TP films were prepared by dip coating method from the TiO_2 sols. The TiO_2 nanorods are smooth with the average diameter of ～65 nm and the length of ～1 μm. The nanorods consist of parallel tiny nanotips about 3-5 nm in diameter on the top surface of the stem nanorod. Morphological evolutions versus reaction time were explored in detail through a series of SEM and XRD characterizations. The results indicated that the size of the rods increased with the reaction time increasing. A thin film sensor was formed from different sizes of single crystalline rutile TiO_2 nanorod arrays growing on a ceramic tube in situ and exhibited an improved triethylamine sensing performance with a fast response of 2 s and a detection limit of 0.1 ppm. The experiment results show that the TiO_2 nanorod arrays are a kind of promising material for detecting trace TEA.