Abstract
In the present work, we have investigated the capacitive hygrometers fabricated by polymer, cellulose, using different
electrodes. Polymer films were deposited by two different deposition methods: spin coater method and by placing the drop
of cellulose suspension in distilled water on primarily deposited electrodes. The DC and AC (at frequency of 20 Hz)
capacitances of the samples were evaluated in the relative humidity range of 30-90%. It was observed that the capacitance
of the cellulose increases with increase in relative humidity level. Comparison of two different methods shows that the drop
coasted films were more sensitive than the spin coated ones where as the response and recovery time of spin coated
samples was much shorter than the drop coasted samples. The relative capacitance ratio to the relative humidity was found
1.5 and 7 for samples deposited by spin coating and drop method, respectively. Humidity dependent capacitive behavior of
cellulose made it attractive for the development of humidity meter.
Keywords
Capacitive hygrometers, Cellulose, Drop method, Relative humidity level.
Citation
ZUBAIR AHMAD, MUHAMMAD H. SAYYAD, KHASAN. S. KARIMOV, Capacitive hygrometers based on natural organic compound, Optoelectronics and Advanced Materials - Rapid Communications, 2, 8, August 2008, pp.507-510 (2008).
Submitted at: June 4, 2008
Accepted at: July 16, 2008