Donor-acceptor bulk-heterojunction sensitizer for efficient solid-state infrared-to-visible photon up-conversion

Area of Science:

• Materials Science
• Photonic Devices
• Organic Electronics

Background:

• Solid-state photon up-conversion is crucial for spectral tailoring but faces challenges.
• Existing methods suffer from low efficiency, high excitation power, limited materials, and complex fabrication.

Purpose of the Study:

• To develop an efficient and scalable method for solid-state photon up-conversion.
• To overcome limitations of current up-conversion technologies.

Main Methods:

• Utilized a bulk-heterojunction sensitizer with energy donor and acceptor components.
• Employed triplet-triplet annihilation up-conversion mechanism.
• Investigated charge separation and charge transfer states at the donor-acceptor interface.

Main Results:

• Achieved a solid-state up-conversion device with 2.20% efficiency.
• Demonstrated efficient up-conversion at low excitation intensity (10 mW cm⁻²).
• Fabricated bright, flexible, large-area up-conversion devices using a one-step solution method.

Conclusions:

• The bulk-heterojunction sensitizer enables efficient charge generation and minimal recombination.
• A simple, scalable platform for fabricating efficient up-conversion devices has been introduced.
• The developed technology offers a promising solution for spectral-tailoring applications.