Liquid PEG and PEGDA as Protective Matrices for TTA-UC Functioning in Air and Their Application in Information...

Area of Science:

• Photochemistry
• Materials Science
• Organic Chemistry

Background:

• Triplet-triplet annihilation upconversion (TTA-UC) is sensitive to oxygen, limiting its applications.
• Polyethylene glycol (PEG) and polyethylene glycol diacrylate (PEGDA) can act as solvents and singlet oxygen scavengers.
• Developing robust TTA-UC systems for practical applications requires addressing oxygen sensitivity.

Purpose of the Study:

• To investigate the use of PEG-200 and PEGDA-575 as solvents and singlet oxygen scavengers for TTA-UC in air.
• To explore the photoinitiated polymerization of PEGDA-575 via TTA and its effect on upconversion properties.
• To develop a high-level information encryption platform based on these findings.

Main Methods:

• TTA-UC experiments were conducted in air using Pt(OEP)/DPA in PEG-200 and PEGDA-575.
• The influence of prolonged 532 nm light irradiation on the Pt(OEP)/DPA/PEGDA-575 system was analyzed.
• A direct-writing method was employed to create information encryption using Pt(OEP)/DPA/PEGDA-575 based inks.

Main Results:

• Upconversion efficiency in aerated PEG-200 was comparable to nitrogen-saturated conditions, indicating effective deoxygenation.
• Photoinitiated polymerization of PEGDA-575 by homomolecular TTA was observed, altering upconversion emission and phosphorescence.
• Successful demonstration of a direct-writing information encryption platform with light-readable and erasable capabilities.

Conclusions:

• Photochemical deoxygenation using PEG-based materials is effective for TTA-UC in ambient conditions.
• The photoinitiated polymerization of PEGDA-575 offers a mechanism for dynamic control of optical properties.
• The developed TTA-UC system provides a novel platform for secure information storage and display.