Abstract
Air pollution is nowadays a big issue regarding the survival of mankind . The development of high-performance, reliable and low-cost NO 2 sensors are urgently needed. Recently, semiconductor gas sensors that do not need any heating element for high-temperature operation have received extensive attention. These sensors present many advantages: low power consumption, low manufacturing cost, as well as moderate stability and safety. Typically, wide bandgap semiconductors have weak, very slow or no response to NO 2 gases at room temperature. Therefore, some enhancing methods like light illumination, organic sensitization, formation of heterojunctions, preparation of composites with 2D materials and introduction of oxygen vacancies in high concentrations have been used to improve the sensing performance according to the published works. These methods and research progress are presented and discussed in this paper.
Highlights
Nitrogen dioxide (NO2) is a toxic gas produced from the combustions of coal, gas, oil or wood for industrial and domestic use
With the development of the fabricating and enhancing technologies in semiconductors and gas sensors, Metal oxide semiconductors (MO) gas sensors are spreading in the direction of low operation temperature, integration and low energy consumption
Reducing the operating temperature to room temperature is of great importance in the field of the stability, structure and power consumption of the sensors
Summary
Nitrogen dioxide (NO2) is a toxic gas produced from the combustions of coal, gas, oil or wood for industrial and domestic use. Our group has done some works in the area of room temperature NO2 sensors, such as light illumination, organic sensitization, forming p-n heterojunctions and introducing high concentration oxygen vacancies. Our group firstly fabricated WO3 films on the substrates of sensors (aluminum oxide with Au interdigital electrode) by screen printing and tested its response to 160 and 320 ppb NO2 under the irradiation of visible light with different wavelengths [5,6] They successfully proved that visible light illumination could effectively improve the response ability of WO3 films to NO2 gas at room temperature. They found that the wavelength and the intensity of visible light have a significant influence on the sensing ability of WO3. When the sensors were exposed to visible lights with a different wavelength, the result indicated that the highest response was measured under the illumination of green light, the response was 31.9 to 1 ppm NO2 while the response time of 16.7 min
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
