Porous plastic optical fiber sensor for ammonia measurement

Area of Science:

• Materials Science
• Chemical Sensing
• Optical Fiber Technology

Background:

• Traditional chemical sensors often struggle with sensitivity and selectivity, especially in complex matrices like aqueous samples.
• Optical fibers offer a promising platform for sensing due to their remote sensing capabilities and immunity to electromagnetic interference.
• Developing materials with controlled porosity is crucial for efficient analyte interaction in sensing applications.

Purpose of the Study:

• To develop and characterize a novel porous plastic optical fiber for chemical gas sensing.
• To investigate the sensing mechanism based on in-line optical absorption within the fiber core.
• To evaluate the fiber's performance for gas concentration measurements in aqueous samples, focusing on high gas permeability and liquid impermeability.

Main Methods:

• Fabrication of a porous plastic optical fiber using copolymer materials with controlled pore size and interconnectivity.
• Implementation of an in-line optical absorption sensing mechanism within the fiber core.
• Testing the developed sensor with an ammonia gas detection system in aqueous samples.

Main Results:

• The porous plastic optical fiber exhibited an interconnective porous structure with uniform pore size.
• The in-line absorption sensing mechanism demonstrated significantly higher sensitivity compared to evanescent coupling methods.
• The fiber showed excellent gas permeability and liquid impermeability, crucial for analyzing gases in aqueous solutions.
• Successful demonstration of ammonia gas sensing in aqueous samples, validating the fiber's effectiveness.

Conclusions:

• The developed porous plastic optical fiber is a highly effective platform for sensitive and selective chemical gas sensing.
• The unique combination of high gas permeability and liquid impermeability makes it ideal for analyzing gaseous analytes in aqueous environments.
• This technology offers a significant advancement for in-situ gas concentration measurements in diverse applications.