Plasticized poly(vinyl chloride)-based photonic crystal for ion sensing

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Sensing

Background:

• Plasticized poly(vinyl chloride) (PVC) is a versatile material for optical applications.
• Two-dimensional photonic crystals (2D-PhCs) offer unique light manipulation properties.
• Developing highly sensitive and selective optical sensors remains a key challenge.

Purpose of the Study:

• To develop a novel plasticized PVC-based 2D-PhC optical sensor.
• To investigate its performance for ion sensing applications.
• To achieve high sensitivity, fast response, and selectivity.

Main Methods:

• Fabrication of plasticized PVC-based 2D-PhC using nanoimprint lithography (NIL).
• Characterization of optical properties, including guided and diffracted light intensity.
• Integration of potassium-selective sensing elements (ionophore and lipophilic dye).
• Monitoring of diffracted peak intensity changes for ion detection.

Main Results:

• A 0.35 μm-thick 2D-PhC film showed the highest diffraction intensity.
• The sensor successfully detected potassium ions (K(+)) with high selectivity.
• Achieved a fast response time of within 5 seconds (95% response).
• Demonstrated a 20-fold increase in sensitivity compared to a standard PVC plane-film optical sensor.

Conclusions:

• The plasticized PVC-based 2D-PhC optical sensor is a promising platform for sensitive and rapid ion detection.
• Nanoimprint lithography enables the fabrication of efficient photonic crystal structures for enhanced sensing.
• The sensor's design offers significant advantages over conventional optical sensors for ion analysis.