Reducing cross-sensitivity of TiO2-(B) nanowires to humidity using ultraviolet illumination for trace explosive detection.
Reducing cross-sensitivity of TiO2-(B) nanowires to humidity using ultraviolet illumination for trace explosive detection.
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DOI：
10.1039/c3cp43454k
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发表时间：
2013-03
期刊：
影响因子：
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通讯作者：
Danling Wang;Antao Chen;A. Jen
中科院分区：
文献类型：
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作者：
Danling Wang;Antao Chen;A. Jen
环境湿度是影响金属氧化物传感性能的重要因素。纳米线形式的 TiO2-(B) 已被证明是一种有前途的材料，可用于检测 2,4,6-三硝基甲苯 (TNT) 等爆炸性气体。然而，消除基于TiO2-(B)的爆炸物探测器对环境湿度的交叉敏感性仍然是一个重大挑战。研究发现，在操作条件下检测爆炸物时，当 TiO2-(B) 纳米线薄膜暴露在紫外 (UV) 光下时，可以有效调节交叉灵敏度。这种紫外光对 TiO2-(B) 纳米线对爆炸物的传感响应的调节归因于光催化效应，TiO2-(B) 纳米线表面吸附的水被分裂，因此传感器响应性能受到的影响较小。结果表明，当暴露于波长365 nm、强度为40 mW cm(-2)的紫外光下时，交叉敏感性可抑制高达51%。这一发现证明，通过紫外线照射降低对湿度的交叉敏感性是一种有效的方法，可以提高基于 TiO2-(B) 纳米线的爆炸性气体检测传感器的性能。
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.