Applied whispering gallery modes on ZnO nanorods coated glass for humidity sensing application

• Main Authors: Jali, Mohd Hafiz, Rahim, Hazli Rafis Abdul, Md Johari, Md Ashadi, Sharif, Maslinda Mat, Johari, Siti Halma, Thokchom, Siddharth, Mohamed, Habibah, Yasin, Moh, Harun, Sulaiman Wadi
• Format: Article
• Published: Tianjin Univ Technology 2021
• Subjects: Optometry. Opticians. Eyeglasses; T Technology (General)
• Online Access: http://eprints.um.edu.my/34839/

In this letter, a humidity sensor is demonstrated by applying a whispering gallery mode (WGM) from a microsphere resonator onto the ZnO nanorods coated glass surface. The diameter of the microsphere was 234 mu m and the glass surface was coated with ZnO nanorods using the hydrothermal method at growth duration of 12 h. A significant response to humidity level ranging from 35%RH to 85%RH has been observed with the sensitivity of 0.014 2 nm/%RH. The proposed humidity sensor has successfully employed to enhance interaction between the whispering gallery mode evanescent and surrounds analyte with the assistance of ZnO nanorods coated glass.