Monolithic Porous Polymer Architectures for Visible-to-UV Upconversion-Driven Photochemical Reactions

Area of Science:

• Materials Science
• Photochemistry
• Polymer Chemistry

Background:

• Triplet-triplet annihilation-based photon upconversion (TTA-UC) extends spectral windows for photochemistry.
• Efficient visible-to-ultraviolet (vis-to-UV) TTA-UC in solid-state polymer materials, especially porous ones, is challenging due to quenching and accessibility issues.

Purpose of the Study:

• To develop robust porous polymer monoliths for efficient solid-state TTA-UC.
• To enable heterogeneous photochemistry using vis-to-UV upconversion under low excitation intensities.
• To create a versatile platform for scalable and sustainable photochemical processes.

Main Methods:

• Embedding sensitizer-annihilator dye pairs into polymer matrices with controlled co-continuous porosity.
• Fabricating monolithic architectures for solid-state TTA-UC.
• Characterizing upconverted emission and evaluating performance under low excitation intensities.

Main Results:

• Demonstrated solid-state TTA-UC in porous polymer monoliths with upconverted UV emission from blue light excitation below a few mW cm^-2.
• Extended operational wavelength to green light excitation.
• Porous architecture enhanced energy transfer to reaction substrates.

Conclusions:

• Porous polymer monoliths enable efficient solid-state TTA-UC, particularly for heterogeneous photochemistry.
• These monoliths serve as promising heterogeneous photoreactors, offering robustness and tunability.
• The developed materials open new avenues for scalable and sustainable photochemistry.