High-Performance Near-Infrared Luminescent Solar Concentrators

Area of Science:

• Materials Science
• Photovoltaics
• Optoelectronics

Background:

• Luminescent solar concentrators (LSCs) can improve photovoltaic (PV) cell performance and reduce system size and cost.
• Near-infrared (NIR) emitting centers are desirable for LSCs to match the spectral response of silicon (Si)-based PV cells.
• Few studies have successfully fabricated NIR-emitting LSCs.

Purpose of the Study:

• To develop and characterize NIR-emitting LSCs using silicon 2,3-naphthalocyanine bis(trihexylsilyloxide) (SiNc) immobilized in a tri-ureasil (t-U(5000)) matrix.
• To evaluate the photophysical properties of the SiNc dye within the matrix.
• To assess the performance of the LSC when coupled to a Si-based PV device.

Main Methods:

• Immobilization of SiNc (NIR775) dye within an organic-inorganic tri-ureasil (t-U(5000)) matrix.
• Characterization of photophysical properties, including emission quantum yield and fluorescence lifetime.
• Coupling of the fabricated LSC with a commercial Si-based PV cell to measure optical conversion efficiency and external quantum efficiency.

Main Results:

• The SiNc dye in the tri-ureasil host exhibited photophysical properties similar to those in solution (quantum yield ~0.17, lifetime ~3.6 ns).
• The LSC coupled to a Si-based PV device achieved an optical conversion efficiency of ~1.5%, a high value for NIR-emitting LSCs.
• The synergistic effect between the t-U(5000) matrix and SiNc molecules led to a significant increase in the PV cell's external quantum efficiency (>20%) within the SiNc absorption band.

Conclusions:

• NIR-emitting LSCs based on SiNc immobilized in a tri-ureasil matrix are feasible and demonstrate promising performance.
• The developed LSCs effectively enhance the performance of Si-based PV cells by increasing their external quantum efficiency.
• This work contributes to the advancement of LSC technology for more efficient and cost-effective solar energy conversion.