Semi-Transparent Luminescent Solar Concentrators Based on Intramolecular Energy Transfer in Polyurethane Matrices

Area of Science:

• Materials Science
• Photovoltaics
• Polymer Chemistry

Background:

• Luminescent solar concentrators (LSCs) offer potential for integrating photovoltaics into various systems.
• Förster-resonance energy transfer (FRET) can enhance LSC performance by minimizing energy losses.
• Linear polyurethanes (PUs) provide synthetic versatility for controlling LSC photophysical properties.

Purpose of the Study:

• To develop novel FRET-based thin-film LSC devices utilizing the synthetic flexibility of linear polyurethanes.
• To control the photophysical properties and device performance of LSCs through material composition.
• To investigate the potential of these LSCs as transparent solar energy devices.

Main Methods:

• Synthesis of luminescent linear polyurethanes (PUs) using novel bis-hydroxyl-functionalized luminophores as chain extenders.
• Incorporation of luminophores via step-growth polyaddition to form a linear macromolecular network.
• Characterization of photophysical properties, energy transfer efficiency, and LSC device performance.

Main Results:

• Achieved high energy transfer efficiency (approximately 90%) between covalently linked luminophores.
• Demonstrated excellent photonic response with external photon efficiency up to approximately 4% and internal photon efficiency up to approximately 37%.
• Optimized power conversion efficiency and enhanced visible-light transmittance.

Conclusions:

• The developed FRET-based PUs are effective for creating high-performance luminescent solar concentrators.
• The synthetic tunability of PUs allows for precise control over LSC optical and performance characteristics.
• These transparent LSCs show significant potential for integration into buildings and portable electronic devices.