title: Volatile organic compound gas sensor based on aluminum-doped zinc oxide with nanoparticle.
abstract: Thick film semiconductor gas sensors based on aluminum-doped zinc oxide (AZO) with nanoparticle size were fabricated to detect volatile organic compound (VOC) existed in building, especially, formaldehyde (HCHO) gas which was known as the cause of sick building syndrome. The sensing materials for screen printing were prepared using roll milling process with binder. The crystallite sizes of prepared materials were about 15 nm through X-ray diffraction (XRD) analysis and scanning electron microscopy (SEM). Gas response characteristics were examined for formaldehyde (HCHO), benzene, carbon monoxide, carbon dioxide gas existing in building. In particular, the sensors showed responses to HCHO gas at sub ppm as a function of operating temperatures and gas concentrations. Also, we investigated sensitivity, repeativity, selectivity, and response time of sensor. The transients were very sharp, taking less than 2 s for 90% response. The sensor has shown very stable response at 350 degrees C and followed a very good behavior and showed 60% response in 50 ppb HCHO concentration at 350 degrees C operating temperatures.
authors.affiliation: Nano Convergence Sensor Research Team, Convergence Components and Materials Research Laboratory, Electronics and Telecommunications Research Institute, Daejeon 305-700, Korea.
authors.forename: Nak-Jin
authors.initials: NJ
authors.lastname: Choi
authors.forename: Hyung-Kun
authors.initials: HK
authors.lastname: Lee
authors.forename: Seung Eon
authors.initials: SE
authors.lastname: Moon
authors.forename: Woo Seok
authors.initials: WS
authors.lastname: Yang
authors.forename: Jongdae
authors.initials: J
authors.lastname: Kim