상세정보
학술지
Highly Sensitive Hydrogen Detection of Catalyst-Free ZnO Nanorod Networks Suspended by Lithography-Assisted Growth
- 저자
- 허정환, 박종혁, 김규태, 박정영
- 발행일
- 201102
- 출처
- Nanotechnology, v.22 no.5, pp.1-7
- ISSN
- 0957-4484
- 출판사
- Institute of Physics (IOP)
- 협약과제
- 10MB3100, 모바일 플렉시블 입출력 플랫폼, 조경익
- 초록
- We have successfully demonstrated a ZnO nanorod-based 3D nanostructure to show a high sensitivity and very fast response/recovery to hydrogen gas. ZnO nanorods have been synthesized selectively over the pre-defined area at relatively low temperature using a simple self-catalytic solution process assisted by a lithographic method. The conductance of the ZnO nanorod device varies significantly as the concentration of the hydrogen is changed without any additive metal catalyst, revealing a high sensitivity to hydrogen gas. Its superior performance can be explained by the porous structure of its three-dimensional network and the enhanced surface reaction of the hydrogen molecules with the oxygen defects resulting from a high surface-to-volume ratio. It was found that the change of conductance follows a power law depending on the hydrogen concentration. A Langmuir isotherm following an ideal power law and a cross-over behavior of the activation energy with respect to hydrogen concentration were observed. This is a very novel and intriguing phenomenon on nanostructured materials, which suggests competitive surface reactions in ZnO nanorod gas sensors. © 2011 IOP Publishing Ltd.
- KSP 제안 키워드
- 3D nanostructure, Activation Energy, Assisted growth, Enhanced surface, Fast response/recovery, High Sensitivity, Highly sensitive, Hydrogen concentration, Hydrogen molecules, Langmuir isotherm, Lithographic method