Abstract
Monolayers of periodic porous Co3O4 inverse opal (IO) thin films for gas-sensor applications were prepared by transferring cobalt-solution-dipped polystyrene (PS) monolayers onto sensor substrates and subsequent removal of the PS template by heat treatment. Monolayer Co3O4 IO thin films having periodic pores (d≈500 nm) showed a high response of 112.9 to 5 ppm C2H5OH at 200 °C with low cross-responses to other interfering gases. Moreover, the selective detection of xylene and methyl benzenes (xylene+toluene) could be achieved simply by tuning the sensor temperature to 250 and 275 °C, respectively, so that multiple gases can be detected with a single chemiresistor. Unprecedentedly high ethanol response and temperature-modulated control of selectivity with respect to ethanol, xylene, and methyl benzenes were attributed to the highly chemiresistive IO nanoarchitecture and to the tuned catalytic promotion of different gas-sensing reactions, respectively. These well-ordered porous nanostructures could have potential in the field of high-performance gas sensors based on p-type oxide semiconductors.
Original language | English |
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Pages (from-to) | 7102-7107 |
Number of pages | 6 |
Journal | Chemistry - A European Journal |
Volume | 22 |
Issue number | 21 |
DOIs | |
Publication status | Published - 2016 May 17 |
Keywords
- monolayers
- nanostructures
- sensors
- template synthesis
- thin films
ASJC Scopus subject areas
- Catalysis
- Organic Chemistry