Mesoporous WN/WO3-Composite Nanosheets for the Chemiresistive Detection of NO2 at Room Temperature
1
Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
2
Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139-4307, USA
*
Author to whom correspondence should be addressed.
Academic Editor: Rainer Niewa
Inorganics 2016, 4(3), 24; https://doi.org/10.3390/inorganics4030024
Received: 13 June 2016 / Revised: 11 July 2016 / Accepted: 21 July 2016 / Published: 26 July 2016
(This article belongs to the Special Issue Novel Solid-State Nitride Materials)
Abstract
Composite materials, which can optimally use the advantages of different materials, have been studied extensively. Herein, hybrid tungsten nitride and oxide (WN/WO3) composites were prepared through a simple aqueous solution route followed by nitriding in NH3, for application as novel sensing materials. We found that the introduction of WN can improve the electrical properties of the composites, thus improving the gas sensing properties of the composites when compared with bare WO3. The highest sensing response was up to 21.3 for 100 ppb NO2 with a fast response time of ~50 s at room temperature, and the low detection limit was 1.28 ppb, which is far below the level that is immediately dangerous to life or health (IDLH) values (NO2: 20 ppm) defined by the U.S. National Institute for Occupational Safety and Health (NIOSH). In addition, the composites successfully lower the optimum temperature of WO3 from 300 °C to room temperature, and the composites-based sensor presents good long-term stability for NO2 of 100 ppb. Furthermore, a possible sensing mechanism is proposed. View Full-TextKeywords:
WN/WO3 composite; nanosheets; gas sensor; NO2; room temperature
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Qu, F.; He, B.; Guarecuco, R.; Yang, M. Mesoporous WN/WO3-Composite Nanosheets for the Chemiresistive Detection of NO2 at Room Temperature. Inorganics 2016, 4, 24.
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Inorganics
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