상세정보
학술지
Ultrafast Response Sensor to Formaldehyde Gas Based on Metal Oxide
- 발행일
- 201408
- 출처
- Journal of Nanoscience and Nanotechnology, v.14 no.8, pp.5807-5810
- ISSN
- 1533-4880
- 출판사
- American Scientific Publishers (ASP)
- 협약과제
- 14MB1600, 스마트&그린 빌딩용 자가충전 지능형 센서노드 플랫폼 핵심기술 개발, 권종기
- 초록
- Thick film semiconductor gas sensors based on indium oxide were fabricated on Si substrate. The sensing materials on Si substrate were characterized using optical microscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM), and so on. They were very fine and uniform and we found out that particle sizes were about 20~30 nm through XRD analysis. Gas responses of fabricated sensors were measured in a chamber where gas flow was controlled by mass flow controller (MFC). Their resistance changes were monitored in real time by using data acquisition board and personal computer. Gas response characteristics were examined for formaldehyde (HCHO) gas which was known as the cause of sick building syndrome. Particularly, the sensors showed responses to formaldehyde gas at sub ppm (cf, standard of natural environment in building is about 80 ppb by ministry of environment in Korea), as a function of operating temperatures and gas concentrations. Also, we investigated sensitivity, repetition, selectivity, response speed and reproducibility of the sensors. The lowest detection limit is HCHO 25 ppb and sensitivity at 800 ppb is over 25% at 350 °C operating temperature. The response time (8 s) and recovery time (15 s) to HCHO gas at 200 ppb were very fast compared to other commercial products in flow type measurement condition. Repetition measurement was very good with 짹3% in full measurement range. The fabricated metal oxide gas sensor showed good performance to HCHO gas and proved that it could be adaptable to indoor environment in building. Copyright © 2014 American Scientific Publishers.
- KSP 제안 키워드
- Commercial products, Data Acquisition(DAQ), Detection limit, Flow controller, Flow type, Formaldehyde gas, Gas flow, Gas response, Indoor Environment, Measurement condition, Measurement range