Using the Transient Response of WO₃ Nanoneedles under Pulsed UV Light in the Detection of NH₃ and NO₂.

Autor: Gonzalez O; MINOS-EMaS, Universitat Rovira i Virgili, Avda. Països Catalans, 26, 43007 Tarragona, Spain. oriol.gonzalez@urv.cat., Welearegay TG; MINOS-EMaS, Universitat Rovira i Virgili, Avda. Països Catalans, 26, 43007 Tarragona, Spain. tesfalemgeremariam.welearegay@urv.cat., Vilanova X; MINOS-EMaS, Universitat Rovira i Virgili, Avda. Països Catalans, 26, 43007 Tarragona, Spain. xavier.vilanova@urv.cat., Llobet E; MINOS-EMaS, Universitat Rovira i Virgili, Avda. Països Catalans, 26, 43007 Tarragona, Spain. eduard.llobet@urv.cat.
Jazyk: angličtina
Zdroj: Sensors (Basel, Switzerland) [Sensors (Basel)] 2018 Apr 26; Vol. 18 (5). Date of Electronic Publication: 2018 Apr 26.
DOI: 10.3390/s18051346
Abstrakt: Here we report on the use of pulsed UV light for activating the gas sensing response of metal oxides. Under pulsed UV light, the resistance of metal oxides presents a ripple due to light-induced transient adsorption and desorption phenomena. This methodology has been applied to tungsten oxide nanoneedle gas sensors operated either at room temperature or under mild heating (50 °C or 100 °C). It has been found that by analyzing the rate of resistance change caused by pulsed UV light, a fast determination of gas concentration is achieved (ten-fold improvement in response time). The technique is useful for detecting both oxidizing (NO₂) and reducing (NH₃) gases, even in the presence of different levels of ambient humidity. Room temperature operated sensors under pulsed UV light show good response towards ammonia and nitrogen dioxide at low power consumption levels. Increasing their operating temperature to 50 °C or 100 °C has the effect of further increasing sensitivity.
Databáze: MEDLINE
Nepřihlášeným uživatelům se plný text nezobrazuje