Dopants Induce Persistent Room Temperature Phosphorescence in Triarylamine Boronate Esters

Area of Science:

• Materials Science
• Photochemistry
• Organic Electronics

Background:

• Room temperature phosphorescence (RTP) materials offer potential for oxygen sensing and information encryption.
• Pure organic materials are cost-effective and environmentally friendly alternatives.
• Previous studies have not focused on the specific bimolecular system of DTBU and TBBU.

Purpose of the Study:

• To develop a novel bimolecular room temperature phosphorescence (RTP) system using DTBU as a guest and TBBU as a host.
• To investigate the impact of doping ratios on the photophysical properties and performance of the DTBU/TBBU system.
• To demonstrate the application of the developed system in oxygen sensing and information encryption.

Main Methods:

• Fabrication of DTBU/TBBU host-guest systems with varying doping concentrations (0.1 mol% and 10 mol%).
• Characterization of RTP properties, including phosphorescence lifetime and sensitivity to oxygen.
• Evaluation of the system's performance in oxygen sensing and information encryption applications.

Main Results:

• Neither pure DTBU nor pure TBBU exhibited RTP in the solid state, even under nitrogen.
• A low doping ratio (0.1 mol%) of DTBU in TBBU resulted in persistent yellowish-green afterglow (340 ms lifetime) highly sensitive to oxygen.
• A higher doping ratio (10 mol%) maintained a phosphorescence lifetime of 179 ms in air.
• Successful demonstration of DTBU/TBBU systems for oxygen sensing and information encryption.

Conclusions:

• Material purity is critical for designing effective RTP systems.
• Host-guest doping in the DTBU/TBBU system allows precise tuning of photophysical properties.
• The proposed energy transfer mechanism involving the T1 state of TBBU facilitates persistent RTP generation.