An Ethanol Vapor Sensor Based on a Microfiber with a Quantum-Dot Gel Coating.

Area of Science:

• Materials Science
• Chemical Sensing
• Nanotechnology

Background:

• Development of sensitive and selective ethanol vapor sensors is crucial for various applications, including environmental monitoring and industrial safety.
• Existing sensor technologies often face challenges related to sensitivity, response time, temperature cross-sensitivity, and fabrication cost.

Purpose of the Study:

• To propose and demonstrate a novel ethanol vapor sensor utilizing a microfiber with a quantum-dot (QD) gel coating.
• To evaluate the sensing performance, including sensitivity, temperature response, and time response, of the fabricated sensor.

Main Methods:

• Fabrication of a QD gel using UV glue as a matrix and Cadmium Selenide/Zinc Sulfide (CdSe/ZnS) QDs at a concentration of 1 mg/mL.
• Development of a simple and low-cost system for the drawing and coating processes.
• Conducting tests for bending, ethanol sensing, temperature response, and time response.

Main Results:

• The sensor exhibited high sensitivity to ethanol vapor (-3.3%/ppm).
• Demonstrated very low temperature cross-sensitivity (0.17 ppm/°C).
• Achieved a fast response time of 1.1 seconds.

Conclusions:

• The easily fabricated, robust microfiber sensor with QD gel coating shows excellent ethanol sensing performance.
• The sensor is a promising platform for practical ethanol sensing applications due to its high sensitivity, low temperature cross-sensitivity, and fast response.