ZnO nanostructure-enhanced tapered polymer optical fiber sensors for pH detection
A. M. ROSLIZAR1,
H. HAROON1,*
,
S. K. IDRIS1,
H. A. RAZAK1,
F. SALEHUDDIN1,
A. S. M. ZAIN1,
N. JUHARI2
Affiliation
- Centre for Telecommunication Research and Innovation, Fakulti Teknologi dan Kejuruteraan Elektronik dan Komputer (FTKEK), Universiti Teknikal Malaysia Melaka (UTeM), Melaka, Malaysia
- Faculty of Electronic Engineering Technology, Universiti Malaysia Perlis, Kampus Alam UniMAP, Arau, Perlis, Malaysia
Abstract
This study presents an experimental investigation of tapered polymer optical fiber (POF) sensors enhanced with zinc oxide
(ZnO) nanostructures for improved pH detection. Both ZnO-coated and uncoated POFs were fabricated and characterized
to evaluate the effects of surface modification and probe length on sensing performance. The sensors were exposed to pH
solutions ranging from 2 to 8, and their optical responses were assessed through variations in refractive index, output
power, and voltage. Results indicate that ZnO-coated POFs exhibit enhanced sensitivity compared to uncoated fibers, with
the 4 cm coated sensor achieving the highest sensitivity of 0.0464 V/pH and a linearity of 98.30%. The ZnO coating
improved the evanescent field interaction by altering the refractive index profile, resulting in greater responsiveness to pHinduced optical changes. These findings highlight the potential of ZnO-coated tapered POFs for high-performance, low-cost
pH sensing in biomedical and environmental applications.
Keywords
Fiber optic sensor, Plastic optical fiber, Tapered plastic optical fiber, Optical sensor, pH sensor.
Citation
A. M. ROSLIZAR, H. HAROON, S. K. IDRIS, H. A. RAZAK, F. SALEHUDDIN, A. S. M. ZAIN, N. JUHARI, ZnO nanostructure-enhanced tapered polymer optical fiber sensors for pH detection, Optoelectronics and Advanced Materials - Rapid Communications, 19, 5-6, May-June 2025, pp.245-250 (2025).
Submitted at: Jan. 15, 2025
Accepted at: June 3, 2025