Relative humidity sensing using a PMMA doped Agarose gel microfiber

Humidity sensors rely on humidity-induced refractive index change in the sensing material despite the sensor configuration. Polymer-based microwires can absorb water vapor molecules and detect humidity changes without the need of further coating. However, the sensitivity-simplicity trade-off is stil...

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Bibliographic Details
Main Authors: Irawati, Ninik, A. Rahman, Husna, Yasin, Moh, Askari, Shadi, Hamida, Belal Ahmed, Ahmad, Harith, W. Harun, Sulaiman
Format: Article
Language:English
English
English
Published: The Optical Society 2017
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Online Access:http://irep.iium.edu.my/58263/
http://irep.iium.edu.my/58263/
http://irep.iium.edu.my/58263/
http://irep.iium.edu.my/58263/1/58263_Relative%20humidity%20sensing.pdf
http://irep.iium.edu.my/58263/2/58263_Relative%20humidity%20sensing_SCOPUS.pdf
http://irep.iium.edu.my/58263/3/58263_Relative%20humidity%20sensing_WOS.pdf
Description
Summary:Humidity sensors rely on humidity-induced refractive index change in the sensing material despite the sensor configuration. Polymer-based microwires can absorb water vapor molecules and detect humidity changes without the need of further coating. However, the sensitivity-simplicity trade-off is still a challenge. Sophisticated coating methods, complex resonating structures and nano-structured films are reported as methods to enhance the device sensitivity. A simple technique, to build a high sensitivity RH sensor based on an agarose-doped Poly Methyl Methacrylate (PMMA) sensor head, is demonstrated. The waist diameter and uniform length of the PMMA doped agarose gel microfiber were measured to be 6 μm and 10 mm, respectively. The sensor can achieve power variation of up to 2.9μW in a wide relative humidity range (50-80%), and display linear response with a correlation coefficient of 98.29 %, sensitivity of 0.421 dB/%RH and resolution of 0.431%RH. This agarose-based optical sensor provides a beneficial complement to the existing electrical ones, and will promote the employment of agarose in chemical sensing techniques.