High-Sensitivity CO₂ Sensor Based on a Graphene Oxide Coated Long-Period Fiber Grating

Area of Science:

• Materials Science
• Optical Sensing
• Environmental Monitoring

Background:

• Accurate carbon dioxide (CO2) monitoring is crucial for environmental and industrial applications.
• Developing sensitive and reliable CO2 sensors remains an active area of research.
• Graphene oxide (GO) possesses unique properties suitable for gas adsorption and sensing.

Purpose of the Study:

• To develop and characterize a novel CO2 sensor.
• To utilize a graphene oxide (GO)-coated long-period fiber grating (LPFG) for CO2 detection.
• To evaluate the sensor's performance, sensitivity, and reliability.

Main Methods:

• Fabrication of a GO-coated LPFG sensor.
• Characterization of GO properties using Raman spectroscopy and scanning electron microscopy (SEM).
• Performance evaluation of the sensor across varying CO2 concentrations (5-65%).

Main Results:

• GO coating exhibited a defective structure, high oxidation, and surface roughness, enhancing adsorption.
• The sensor demonstrated a sensitivity of 0.0643 nm/% for CO2 detection.
• High linearity (approx. 96%) and low hysteresis were observed during adsorption and desorption cycles.

Conclusions:

• The GO-coated LPFG sensor is a promising technology for practical CO2 sensing.
• The sensor offers advantages like electromagnetic interference immunity and remote sensing integration.
• This development contributes to advancements in environmental monitoring and gas sensing technologies.