Design optimization and stability enhancement of modified inter-digital capacitive humidity transducer with cobalt ferrite nanoparticles as dielectric. (February 2020)

• Record Type: Journal Article
• Authors: Paul, Jiss; Philip, Jacob
• Other Names: Tan Chao guest-editor.
• Is Part Of: Transactions of the Institute of Measurement and Control. Volume 42:Number 4(2020)
• Page Start: 917
• Page End: 923
• Publication Date: 2020-02
• Subjects: Inter-digital capacitive sensor -- relative humidity -- polyvinyl alcohol -- CoFe2O4 nanoparticles; Automatic control -- Periodicals; Measuring instruments -- Periodicals; Commande automatique -- Périodiques; Mesure -- Instruments -- Périodiques; 681.2
• DOI: 10.1177/0142331219889485
• Languages: English
• ISSNs: 0142-3312

Abstract

A modified inter-digital capacitive (IDC) transducer for relative humidity (RH) measurement is fabricated by coating a thick film of polyvinyl alcohol (PVA) on the structure. The effective capacitance of the sensor, measured at 1MHz, increases with RH at room temperature. The RH sensing characteristics of PVA coated IDC transducer are analysed in terms of its sensitivity, dynamic range, frequency response, repeatability and recovery time. It is found that the stability of such a PVA based RH transducer improves remarkably by diffusing nanoparticles of CoFe2 O4 in the PVA layer. A standard deviation of ± 0.05 and ± 0.01 for a sensitive layer with pure PVA and PVA-CoFe2 O4 combination respectively results in a measurement error of ± 0.005 and ± 0.003.