Efficient luminescent solar concentrators based on solvent polarity induced multiple-colored carbon dots

Area of Science:

• Materials Science
• Renewable Energy
• Nanotechnology

Background:

• Luminescent solar concentrators (LSCs) are key for building-integrated photovoltaics (BIPV).
• High-performance LSCs require fluorophores with broad absorption, high quantum yield, and large Stokes shift.
• Conventional LSCs often use heavy metal-based quantum dots, posing environmental concerns.

Purpose of the Study:

• To demonstrate highly efficient LSCs using boron-doped carbon nanodots (B-C-dots) as heavy metal-free fluorophores.
• To investigate the influence of solvent and polymer polarity on the optical properties of B-C-dots.
• To tune the color and performance of LSCs for BIPV applications.

Main Methods:

• Hydrothermal synthesis of B-C-dots and undoped carbon nanodots.
• Dispersion of B-C-dots in various solvents (ethanol, hexane, toluene) and polymer matrices (PMMA, PS).
• Characterization of optical properties (absorption and emission spectra) and fabrication of LSC devices.

Main Results:

• B-C-dots exhibit solvent-dependent optical properties, with emission redshift in less polar solvents like toluene.
• Dispersion in polymers leads to varied emission peaks due to different refractive indices.
• An optimized B-C-dot/PS LSC achieved 5.48% optical efficiency under natural sunlight.

Conclusions:

• Understanding B-C-dot polarity is crucial for tuning LSC performance.
• B-C-dots offer a pathway to low-cost, efficient, and environmentally friendly LSCs for BIPV.
• This work provides a simple method for color tuning and performance enhancement in LSCs.