Dicarbocyanine-based organic humidity sensors
Document Type
Article
Publication Date
3-1-2023
Abstract
The utilization of organic dicarbocyanine dye-conjugated molecules, specifically 1,1 `-diethyl-4,4 `-dicarbocyanine iodide (DDCI-4), as the sensing film in capacitive-type humidity sensors has been demonstrated. The structural, morphological, and wettability characteristics of the sensing films as well as the performance of the electrode gaps of the devices were analyzed. Aluminum (Al)/DDCI-4/Al capacitive humidity sensors were fabricated using solution-processed spin coating techniques in a planar geometry. In this study, a surface profiler was used to measure the size of electrode gaps, which were 94.87 +/- 1.20 mu m, 391.00 +/- 1.53 mu m, 902.00 +/- 2.08 mu m, and 1906.67 +/- 3.33 mu m. Compared to those with larger gaps (391 mu m, 902 mu m, and 1907 mu m), the device with the smallest gap measured 45 +/- 9.1 fF/%RH with the highest sensitivity. In addition, the hysteresis with response and recovery performances has been studied, revealing the lowest values of 0.31%, 6 s, and 9 s, respectively. It is anticipated that the 1,1 `-diethyl-4,4 `-dicarbocyanine iodide's electronic, ionic, and dipole polarizations are responsible for the excellent performance of dye-based organic humidity sensors.
Keywords
Dye, Conjugated molecules, Humidity sensor, Capacitive, Polarization
Divisions
PHYSICS
Funders
Universiti Malaya under the Faculty Research Grant GPF080A- 2020
Publication Title
Synthetic Metals
Volume
293
Publisher
Elsevier
Publisher Location
PO BOX 564, 1001 LAUSANNE, SWITZERLAND