Highly Sensitive Sensors Based on Metal-Oxide Nanocolumns for Fire Detection.
A fire detector is the most important component in a fire alarm system. Herein, we present the feasibility of a highly sensitive and rapid response gas sensor based on metal oxides as a high performance fire detector. The glancing angle deposition (GLAD) technique is used to make the highly porous structure such as nanocolumns (NCs) of various metal oxides for enhancing the gas-sensing performance. To measure the fire detection, the interface circuitry for our sensors (NiO, SnO₂, WO₃ and In₂O₃ NCs) is designed. When all the sensors with various metal-oxide NCs are exposed to fire environment, they entirely react with the target gases emitted from Poly(vinyl chlorides) (PVC) decomposed at high temperature. Before the emission of smoke from the PVC (a hot-plate temperature of 200 °C), the resistances of the metal-oxide NCs are abruptly changed and SnO₂ NCs show the highest response of 2.1. However, a commercial smoke detector did not inform any warning. Interestingly, although the NiO NCs are ap-type semiconductor, they show the highest response of 577.1 after the emission of smoke from the PVC (a hot-plate temperature of 350 °C). The response time of SnO₂ NCs is much faster than that of a commercial smoke detector at the hot-plate temperature of 350 °C. In addition, we investigated the selectivity of our sensors by analyzing the responses of all sensors. Our results show the high potential of a gas sensor based on metal-oxide NCs for early fire detection.
Contents Convergence Research Center, Korea Electronics Technology Institute (KETI), 11, World cup buk-ro 54-gil, Seoul 03924, Korea. begleam@keti.re.kr.
Kwangjae
K
Lee
Center for Electronic Materials, Korea Institute of Science and Technology (KIST), 5, Hwarang-ro 14-gil, Seongbuk-gu, Seoul 136-791, Korea. ysshim@kist.re.kr.
Young-Seok
YS
Shim
Center for Electronic Materials, Korea Institute of Science and Technology (KIST), 5, Hwarang-ro 14-gil, Seongbuk-gu, Seoul 136-791, Korea. songyg6397@kist.re.kr.
Young Geun
YG
Song
Center for Electronic Materials, Korea Institute of Science and Technology (KIST), 5, Hwarang-ro 14-gil, Seongbuk-gu, Seoul 136-791, Korea. 113341@kist.re.kr.|KU-KIST Graduate School of Converging Science and Technology, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul 136-701, Korea. 113341@kist.re.kr.
Soo Deok
SD
Han
Contents Convergence Research Center, Korea Electronics Technology Institute (KETI), 11, World cup buk-ro 54-gil, Seoul 03924, Korea. yslee@keti.re.kr.
Youn-Sung
YS
Lee
Center for Electronic Materials, Korea Institute of Science and Technology (KIST), 5, Hwarang-ro 14-gil, Seongbuk-gu, Seoul 136-791, Korea. cykang@kist.re.kr.|KU-KIST Graduate School of Converging Science and Technology, Korea University, 145, Anam-ro, Seongbuk-gu, Seoul 136-701, Korea. cykang@kist.re.kr.
Chong-Yun
CY
Kang
fire detection; gas sensor; nanostructures