Tungsten oxide-based semiconductor sensor for detection of nitrogen oxides in combustion exhaust

Metal Oxide Sensors: New Devices Through Tailoring Interfaces on the Atomic Scale

“…The sensitivity to monitor NO with WO 3 , for example, increases with decreasing temperature. Typical operating temperatures are around 300 °C [112][113][114]. TiO 2 -based sensors, in contrast, show a typical maximum in NO sensitivity at 450°C [111].…”

Copper tungstate thin-films for nitric oxide sensing

“…Specifically, two major strategies have been used to improve sensor performance: i) WO 3 in combination with catalytic metals [8][9][10] and ii) metal-oxide composite formulations with the use of a metal-oxide cocatalyst [11][12][13][14]. The present work reports the latter as the experimental strategy to enhance the sensing profile of WO 3 , specifically using novel (CuWO 4 ) thin-films.…”

“…Previous studies have shown that WO 3 is a material highly suited for the real-time monitoring of gas-phase pollutants (conductometric sensing phase), particularly for NO x monitoring [6][7][8][9][10][11][12][13][14].…”

NOx Sensing with n-type WO3 - CuWO4 Composites

“…Equation 1 summarizes the fundamental process that renders CuWO 4 thin-film (F-8) suitable for sensing redox gas-phase species; that is, gas-phase species that undergo a redox change upon interaction with surface states within the semiconductor surface such as O 2 . (3,4,5,7,8) …”

“…conductometric sensor prototype), and particularly for NO x monitoring technology. 7 Specifically, two major strategies have been used to improve WO 3 conductometric sensor performance, i) in combination with catalytic metals (8,9,10,11) and ii) composite formulations with other semiconductor oxides. (7,12,13,14,15,16) The present work reports the latter as the experimental strategy to complement the sensing profile of WO 3 , increasing by this means the range of sensing functionality for NO x species.…”