Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7148608 | Sensors and Actuators B: Chemical | 2013 | 8 Pages |
Abstract
We present a highly fast capacitive humidity sensor based on superhydrophilic carbon nanotube network electrodes prepared by using spray deposition of multiwalled carbon nanotubes (MWCNT). Spray-deposited MWCNT films form a well-entangled and interconnected porous network with nano-scale open pores. These properties are highly desirable for fast-speed capacitive humidity sensors. In addition, the effect of plasma functionalization (pf) of the MWCNT surface on sensor response was evaluated. The pf-MWCNT electrode sensor exhibited a much faster response time (about 1.5Â s) and a higher sensitivity (0.647Â pF/%RH) to humidity, compared to untreated MWCNT and porous Cr electrodes. The large improvement in performance was explained by the percolated pore network, which is more accessible to water molecules; the superhydrophilic surface of the MWCNTs favorable to more adsorption of water vapor; and capillary condensation, which can amplify the capacitance response to relative humidity.
Related Topics
Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
Myung Jin Lee, Hyun Pyo Hong, Kwang Ho Kwon, Chan Won Park, Nam Ki Min,