High-performance laminated luminescent solar concentrators based on colloidal carbon quantum dots

Area of Science:

• Materials Science
• Renewable Energy
• Nanotechnology

Background:

• Luminescent solar concentrators (LSCs) offer a lightweight, semitransparent solution for solar energy conversion.
• Carbon quantum dots (C-QDs) possess tunable optical properties and high quantum yields, making them promising for LSCs.
• Challenges remain in fabricating high-efficiency C-QD based LSCs due to spectral overlap issues.

Purpose of the Study:

• To fabricate high-efficiency, large-area, semitransparent laminated LSCs using carbon quantum dots.
• To investigate the impact of C-QD concentration on LSC performance.
• To evaluate the solar energy harvesting potential and photostability of the developed LSCs.

Main Methods:

• Fabrication of semi-transparent, large-area (10 × 10 cm²) laminated LSCs using C-QDs.
• Optimization of C-QD concentration within the laminated structure.
• Characterization of optical properties, including absorption and emission spectra, and Stokes shift.
• Measurement of optical efficiency (η_opt) and power conversion efficiency under simulated and natural sunlight.

Main Results:

• The fabricated C-QDs exhibit absorption from 300 to 550 nm with a 0.6 eV Stokes shift.
• Optimized laminated LSCs achieved a highest optical efficiency (η_opt) of 1.6%, a 1.6-fold increase over single-layer LSCs.
• A power conversion efficiency of 0.7% was recorded under natural sunlight (62 mW cm⁻²), alongside excellent photostability.

Conclusions:

• Laminated LSC structures demonstrate superior performance for solar energy harvesting compared to single-layer or tandem designs.
• Optimized C-QD concentration is crucial for maximizing the efficiency of laminated LSCs.
• These findings highlight the potential of laminated C-QD LSCs for efficient and stable solar energy applications.