Polyelectrolyte/Graphene Oxide Nano-Film Integrated Fiber-Optic Sensors for High-Sensitive and Rapid-Response...

Area of Science:

• Materials Science
• Photonics
• Sensor Technology

Background:

• Optical fiber sensors are valuable for various applications due to their unique properties.
• Existing sensors face challenges in balancing sensitivity, response time, temperature interference, and hysteresis.
• Graphene oxide (GO) and polyelectrolyte nanocomposites show promise for enhancing sensor performance.

Purpose of the Study:

• To develop a high-performance optical fiber humidity sensor overcoming current limitations.
• To leverage the properties of GO/polyelectrolyte nanocomposites and excessively tilted fiber gratings (ex-TFG) for improved humidity sensing.
• To achieve a sensor with high sensitivity, rapid response/recovery, low hysteresis, and minimal temperature crosstalk.

Main Methods:

• Coating a functional graphene oxide (GO)/polyelectrolyte nanocomposite film onto an excessively tilted fiber grating (ex-TFG).
• Utilizing the hydrophilicity of the nanocomposite film to accelerate water molecule adsorption/desorption.
• Employing the ex-TFG structure to enhance refractive index sensitivity and mitigate temperature crosstalk.

Main Results:

• The developed sensor demonstrated high sensitivity and a rapid response and recovery to humidity changes.
• The sensor exhibited low hysteresis and negligible temperature crosstalk across a wide relative humidity (RH) range.
• Excellent repeatability and long-term stability were observed, confirming the sensor's reliability.

Conclusions:

• The GO/polyelectrolyte nanocomposite coated ex-TFG sensor offers a promising solution for accurate and reliable humidity monitoring.
• This innovative sensor platform addresses the trade-offs in traditional optical fiber humidity sensors.
• The sensor is suitable for diverse applications including rapid diagnostics, pharmaceuticals, and precision medicine.