Ultra-low NO2 detection by gamma WO3 synthesized by Reactive Spray Deposition Technology

Abstract

a b s t r a c tA porous tungsten oxide (WO 3 ) NO 2 sensor was developed by a one-step flame based process called Reactive Spray Deposition Technology (RSDT). This nano-crystalline WO 3 film was deposited directly on gold interdigitated electrodes. The sensing characteristics of this NO 2 sensor was measured at the parts per million (ppm) level, (0.17-5 ppm in air) at 300 • C. The sensors showed a relatively fast response time (∼7s) and recovery time (∼5 min), respectively. The stability of the sensor was evaluated for 300 h in 0.5 ppm NO 2 at 300 • C in (2000 response-recovery cycles). The sensor was stable up to 6 days (∼150 h) of continuous operation and degraded between 150-300 h. The morphology and surface properties of the WO 3 film were investigated with XRD, Raman spectroscopy, BET, SEM, TEM, and HRTEM.

Enhanced Triethylamine Sensing Properties by Designing an α-Fe2O3/α-MoO3 Nanostructure Directly Grown on Ceramic Tubes

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Palladium (II) Oxide Nanostructures as Promising Materials for Gas Sensors

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Nitrogen dioxide gas-sensing properties of hydrothermally synthesized WO 3 · nH 2 O nanostructures

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