Advanced Optimization of Optical Carbon Dioxide Sensor Through Sensitivity Enhancement in Anodic Aluminum Oxide...

Area of Science:

• Materials Science
• Chemical Sensing
• Nanotechnology

Background:

• Accurate carbon dioxide (CO2) monitoring is crucial for medical and industrial applications.
• Existing CO2 sensors face challenges with sensitivity, stability, and interference from excitation light.
• Development of novel optical sensing materials is needed for improved CO2 detection.

Purpose of the Study:

• To develop a sensitive and stable optical carbon dioxide (CO2) sensor.
• To utilize CdSe/ZnS quantum dots (QDs) and Phenol Red on an anodized aluminum oxide (AAO) substrate for CO2 detection.
• To investigate the photoluminescence properties and sensing performance of the developed sensor.

Main Methods:

• Fabrication of an optical CO2 sensor by embedding CdSe/ZnS QDs and Phenol Red in a polyIBM matrix on an AAO substrate.
• Characterization of the sensor using photoluminescence spectroscopy with a 405 nm LED excitation source.
• Evaluation of sensor performance including sensitivity, linear detection range, response time, and recovery time.

Main Results:

• The sensor exhibited red fluorescence emission at 570 nm and detected CO2 in the 0-100% range.
• Fluorescence intensity increased with CO2 concentration, showing a sensitivity of 211.
• A wavelength shift of 0.1657 nm/% indicated strong interactions within the sensor matrix. Response and recovery times were 55 s and 120 s, respectively.

Conclusions:

• The AAO-supported QD and Phenol Red composite offers a reliable and effective optical CO2 sensing material.
• The developed sensor minimizes fluctuations from the excitation light source, enhancing detection accuracy.
• This optical sensing approach shows significant potential for CO2 monitoring in medical and industrial fields.