Efficiency of Thermally Activated Delayed Fluorescence Sensitized Triplet Upconversion Doubled in Three-Component...

Area of Science:

• Materials Science
• Photochemistry
• Organic Electronics

Background:

• Photon upconversion (UC) research aims to enhance efficiency and performance while reducing production costs.
• Metal-free thermally activated delayed fluorescence (TADF) sensitizers are gaining interest for UC applications.
• Ternary systems offer potential for improved energy transfer dynamics in UC.

Purpose of the Study:

• To investigate the efficacy of a ternary photon upconversion system utilizing a metal-free TADF sensitizer.
• To enhance the upconversion quantum yield (UQY) by employing an energy-funneling strategy.
• To evaluate the performance of the ternary system in terms of UQY and anti-Stokes shift.

Main Methods:

• Fabrication of a ternary photon upconversion system comprising 4CzIPN (sensitizer), 1-methylnaphthalene (intermediate acceptor), and p-terphenyl (emitter).
• Utilized an energy-funneling strategy within the ternary blend.
• Measured the normalized upconversion quantum yield and anti-Stokes shift.

Main Results:

• Achieved a normalized upconversion quantum yield of 7.6% in the ternary system.
• Demonstrated a doubling of the UQY compared to a binary system using p-terphenyl as the emitter.
• Maintained an anti-Stokes shift of 0.83 eV.

Conclusions:

• Ternary photon upconversion with metal-free TADF sensitizers is a viable strategy for enhancing performance.
• The energy-funneling approach, previously limited to heavy-metal systems, effectively boosts UC efficiency.
• This work presents a promising, cost-effective pathway for advanced photon upconversion technologies.