Synergistic Fluorescence with Significant Red Shift in Coumarin-Doped PMMA Matrices Using CdTe Quantum Dots for...

Area of Science:

• Materials Science
• Nanotechnology
• Optoelectronics

Background:

• Luminescent concentrators (LCs) offer potential for non-imaging applications.
• Integrating quantum dots (QDs) can enhance the photophysical properties of LCs.
• Precise position sensing is crucial for industrial and smart city development.

Purpose of the Study:

• To fabricate and calibrate luminescent concentrators (LCs) as high-precision non-imaging position sensors.
• To investigate the effect of Cadmium Telluride (CdTe) quantum dots (QDs) concentration on LC photophysical properties.
• To evaluate the performance of optimized LCs for position sensing applications.

Main Methods:

• Fabrication of 15×10×0.3 cm LCs using PMMA/chloroform solutions doped with coumarin dye and varying concentrations of CdTe QDs.
• Characterization using X-ray Diffraction (XRD), UV-vis absorption, and fluorescence polarization spectroscopy.
• Performance evaluation of LC position sensors for horizontal and vertical displacement detection.

Main Results:

• Increasing CdTe QD concentration significantly enhanced photophysical properties, including a 58 nm redshift and improved fluorescence quantum yield (90.05% to 94.76%) at 0.8 wt% concentration.
• Optimal QD concentration (0.8 wt%) yielded the highest fluorescence anisotropy, confirmed by polarization measurements.
• LC position sensors demonstrated excellent sensitivity (99.75%) for detecting displacements in 10-micron increments.

Conclusions:

• Optimized CdTe QD concentrations in LCs significantly enhance photophysical properties and enable high-precision position sensing.
• The developed LCs show promise as efficient position sensors for wide-area detection.
• These findings support sustainable development goals related to industrial growth and smart cities.