ZnO coated nanospring-based chemiresistors
Abstract
Chemiresistors were constructed using 3-D silica nanospring mats coated with a contiguous film of ZnO nanocrystals. Chemiresistors with an average ZnO nanocrystal radius <3 nm, or >20 nm, were found to exhibit a relative change in conductance of a factor of 50 upon exposure to a gas flow of 20% O2 and 80% N2 with ∼500 ppm of toluene and an operational temperature of 400 °C. Samples with an average ZnO nanocrystal radius of 15 nm were found to be the most responsive with a relative conductance change of a factor of 1000. The addition of metal nanoparticles (average radius equal to 2.4 nm) onto the surface of the ZnO nanocrystals (average radius equal to 15 nm) produced a relative change in conductance of a factor of 1500. For the optimum conditions (T = 400 °C, grain size ∼15 nm) well-defined spikes in conductance to explosive vapors (TNT, TATP) were obtained for 0.1 ms exposure time at ppb levels.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Feb 15, 2012
- Source ID
- 10.1063/1.3686212
Entities
People
- Alex Kengne
- Alexander Larin
- D. N. Mcilroy
- Dewayne Sowell
- Giancarlo Corti
- Jessica Hall
- Joseph Williams
- Landon Oakes
- Pavel Bakharev
- Tej Prakash
- Timothy Cantrell
- Vladimir Dobrokhotov
Organizations
- Office of Naval Research
- University of Idaho
- University of Louisville
- Western Kentucky University