Impact of Compositional Engineering on PTB7-Th:PC71BM Capacitive Humidity Sensor Performance
Document Type
Article
Publication Date
11-1-2024
Abstract
The current investigation focuses on the development of capacitive humidity sensors utilizing an organic polymer blend of poly4,8-bis(5-(2-ethylhexyl)thiophene-2-yl)benzo1,2-b;4,5-b `]dithiophene-2,6-diyl-alt-(4-(2-ethylhexyl)-3-fluorothieno3,4-b]thio phene-)-2-carboxylate-2-6-diyl)] (PTB7-Th) and 6,6]-phenyl-C71-butyric-acid methyl ester (PC71BM), which were successfully achieved. A cost-effective spin-coating technique was employed to produce surface-type sensors in the Al/PTB7-Th:PC71BM/Al horizontal geometry. The investigation focuses on the capacitive behavior of the devices under ambient conditions, specifically at room temperature. The devices are subjected to an alternating current operational bias of 1 V, while the relative humidity (RH) is varied within the range of 20-95%. The sensors are examined at frequencies of 100 Hz, 1 kHz, 10 kHz, and 100 kHz. Specifically, the sensors demonstrate improved sensitivity to changes in capacitance in relation to relative humidity when operating at a frequency of 100 Hz. In addition, an optimal volumetric ratio of 1.5:1 is selected for PTB7-Th to PC71BM. The optimized composite sensor demonstrates superior performance, exhibiting minimal hysteresis of 6.16% and significant sensitivity of 1.58 pF/% RH. In addition, response and recovery times of 2 s and 3 s, respectively, are obtained. The results of investigations demonstrate that the composite sensor exhibits significant improvements in sensing parameters compared to single-material sensors. As a result, the composite sensor has great potential for use in advanced sensor applications, especially in the education sector in underdeveloped countries.
Keywords
Capacitance, humidity sensor, organic semiconductor, polymer composite, surface-type
Divisions
PHYSICS
Funders
Universiti Malaya,Higher Education Commission of Pakistan
Publication Title
Journal of Electronic Materials
Volume
53
Issue
11, SI
Publisher
Springer
Publisher Location
ONE NEW YORK PLAZA, SUITE 4600, NEW YORK, NY, UNITED STATES