M.B. Anargiansyah, F.R.A. Pramudya, B.R.P. Fayensi, R.N. Hikmah, M.F. Ghani, M. Khoiro
The detection of Cadmium (Cd) in palm oil using optical fiber sensors had been simulated utilizing the Finite Element Method (FEM) approach to investigate sensor performance. The optical fiber sensor was developed using chitosan reagents for better detection performance. The optical fiber was built using a silica core with a refractive index of 1.45, and cladding was replaced by the result reaction between chitosan and oil with a refractive index of 1.333. The study aims to observe the effect of reagent thickness that varied 0.1 to 0.5 mm for sensor performance to detect Cd in oil with a concentration variation of 0.05 - 0.5 ppm using a 650 nm red beam source. The results show that increasing the reagent's thickness can reduce the beam's confinement factor in optical fiber from 90.224 to 61.975. The reduction can be due to the mismatching of the refractive index between the core and cladding. The performance of the optical fiber sensor was examined using loss propagation and confinement factor in Cd concentration variation. For each reagent thickness, the results indicated that the loss propagation increased, and on the contrary, the confinement factor decreased as Cd concentration increased. The highest sensitivity of the sensor, calculated from the slope of the concentration vs. confinement factor graph, was obtained while using 0.5 cm reagent thickness with the value of 1.6267. It indicated that the reagent thickness could improve the optical fiber sensor performance, especially on Cd detection in oil. © 2024 Institute of Physics Publishing. All rights reserved.
Physics Department, Universitas Negeri Surabaya, Surabaya, Indonesia
