Open AccessTemperature self-calibrated pH sensor based on GO/PVA-coated MZI cascading FBG
Author(s) -
Ran Yan,
Guofeng Sang,
Bin Yin,
Songhua Wu,
Muguang Wang,
Benran Hou,
Mingquan Gao,
Rong Chen,
Han Young Yu
Publication year - 2021
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.421782
Subject(s) - materials science , fiber bragg grating , fiber optic sensor , photonic crystal fiber , interferometry , optics , optical fiber , fiber , repeatability , mach–zehnder interferometer , refractive index , attenuation coefficient , optoelectronics , wavelength , composite material , chemistry , physics , chromatography
A temperature self-calibrated potential of hydrogen (pH) sensor based on the single mode fiber-tapered dual core photonic crystal fiber-single mode fiber (SMF-TDCPCF-SMF) structure cascaded with a fiber Bragg grating (FBG) is proposed and demonstrated. The TDCPCF structure formed Mach-Zehnder interferometer (MZI) is modified with a coating of graphene oxide/polyvinyl alcohol (GO/PVA) hybrid hydrogel to realize the measurement of pH, and the uncoated FBG is used to calibrate temperature. In our experiment, the sensitivity coefficient of 0.69 nm/pH with R 2 =0.99 and the hysteresis loss of less than 0.007 are achieved within the pH range from pH 4.00 to pH 9.85. The measured response time from pH 7.00 to pH 4.00, 6.00 and 9.85 are no higher than 10s. Moreover, the resonant wavelengths of MZI and FBG also exhibit good linear relationship with the temperature sensitivity coefficient of 0.15 nm/°C (R 2 =0.99) and 0.09 nm/°C (R 2 =0.97) respectively. It is demonstrated successfully that the proposed sensor has broad application prospects in the field of environmental monitoring, biological sensing and chemical analysis, due to the good performance of the temperature self-calibrated pH monitoring, repeatability, linearity, response time and reversibility.