Over the past few decades, the detection of nitrogen dioxide (NO2) in combustion exhaust or in the environment has been of significant interest because the presence of NO2 has been correlated to the formation of acid rain, photochemical smog and some respiratory diseases including emphysema and bronchitis. Several types of NO2 sensors have been developed including chemiresistive, potentiometric, and amperometric, based on metal oxides (for example, WO3, SnO2, ZnO, NiO and ZrO2). However, metal oxide based sensors can require high operating temperatures in order to obtain decent sensitivities and faster response/recovery times. High operating temperatures can significantly reduce selectivity, while also increasing power consumption and device complexity.Researchers at the University of California, Riverside have developed a NO2 gas sensor operable at ambient conditions. The sensor includes functionalized feather-like tellurium (Te) nanostructures on single-walled carbon nanotube (SWNTs) networks.
|United States Of America||Issued Patent||9,632,057||04/25/2017||2012-850|