2D materials coated on etched optical fibers as humidity sensor

Area of Science:

• Materials Science
• Nanotechnology
• Optical Engineering

Background:

• Humidity sensors are crucial for environmental monitoring and industrial processes.
• Developing novel materials for enhanced humidity sensing performance is an active research area.
• Optical fiber sensors offer advantages like remote sensing and electromagnetic immunity.

Purpose of the Study:

• To investigate the humidity sensing properties of etched single-mode fibers coated with 2D materials.
• To evaluate the performance of Molybdenum disulfide (MoS2), Molybdenum diselenide (MoSe2), and graphene/graphene oxide (G/GO) coatings.
• To determine the suitability of these sensors for different relative humidity (RH) ranges.

Main Methods:

• Etched single-mode fibers (ESMF) were coated with MoS2, MoSe2, and G/GO.
• Relative differentiation of attenuations (RDA) was measured using an Optical Loss Test Set.
• Measurements were conducted at telecommunication wavelengths (1310 nm and 1550 nm) across various RH levels.

Main Results:

• ESMF coated with G/GO exhibited a high, monotonic RDA response for RH > 30%, with reasonable sensitivity and variance.
• MoSe2-coated sensors showed high RDA below 30% RH but lost their monotonic function at higher humidity.
• ESMF coated with MoS2 demonstrated indistinctive behavior, rendering it unsuitable for humidity sensing.

Conclusions:

• G/GO coated ESMF presents a viable option for humidity sensing applications, particularly in the higher RH range.
• MoSe2 coated ESMF is suitable for low humidity (<30%) sensing.
• The choice of 2D material coating significantly impacts the performance and applicable RH range of optical fiber humidity sensors.