title: Reducing cross-sensitivity of TiO2-(B) nanowires to humidity using ultraviolet illumination for trace explosive detection.
abstract: Environmental humidity is an important factor that can influence the sensing performance of a metal oxide. TiO2-(B) in the form of nanowires has been demonstrated to be a promising material for the detection of explosive gases such as 2,4,6-trinitrotoluene (TNT). However, the elimination of cross-sensitivity of the explosive detectors based on TiO2-(B) toward environmental humidity is still a major challenge. It was found that the cross-sensitivity could be effectively modulated when the thin film of TiO2-(B) nanowires was exposed to ultraviolet (UV) light during the detection of explosives under operating conditions. Such a modulation of sensing responses of TiO2-(B) nanowires to explosives by UV light was attributed to a photocatalytic effect, with which the water adsorbed on the TiO2-(B) nanowire surface was split and therefore the sensor response performance was less affected. It was revealed that the cross-sensitivity could be suppressed up to 51% when exposed to UV light of 365 nm wavelength with an intensity of 40 mW cm(-2). This finding proves that the reduction of cross-sensitivity to humidity through UV irradiation is an effective approach that can improve the performance of a sensor based on TiO2-(B) nanowires for the detection of explosive gas.
authors: Applied Physics Laboratory & Electrical Engineering, University of Washington, Seattle, Washington 98105, USA.
authors: Danling
authors: D
authors: Wang
authors: Antao
authors: A
authors: Chen
authors: Alex K-Y
authors: AK
authors: Jen
mesh_terms: D001895:Boron / Q000737:chemistry*; D006813:Humidity; D053770:Nanowires / Q000737:chemistry*; D010084:Oxidation-Reduction; D014025:Titanium / Q000737:chemistry*; D014303:Trinitrotoluene / Q000032:analysis*; D014466:Ultraviolet Rays
chemical_list: D014303:Trinitrotoluene; C009495:titanium dioxide; D014025:Titanium; D001895:Boron