Achieving Tunable Monomeric TADF and Aggregated RTP via Molecular Stacking

Area of Science:

• Organic electronics
• Materials science
• Photophysics

Background:

• Organic emitters with thermally activated delayed fluorescence (TADF) and room-temperature phosphorescence (RTP) are of significant interest.
• TADF and RTP offer unique luminescent properties for advanced applications.

Purpose of the Study:

• To develop novel organic emitters exhibiting both TADF and RTP properties.
• To understand and control the mechanisms governing dual-channel emission.

Main Methods:

• Synthesis of triphenylamine-substituted isoquinoline derivatives.
• Investigation of molecular stacking (π-π and charge transfer) and its influence on luminescence.
• Modulation of TADF and RTP through molecular design and external stimuli.

Main Results:

• Achieved monomeric TADF and aggregated RTP in the synthesized derivatives.
• Demonstrated tunable TADF-RTP emission by controlling inter/intramolecular charge transfer (CT).
• Established that aggregated phosphorescence arises from intermolecular CT, while monomeric TADF is due to intramolecular CT.

Conclusions:

• Molecular substitution position alignment, solvent effects, grinding, concentration, polymer matrix, photoactivation, and heat treatment allow for tunable TADF-RTP properties.
• This work provides critical insights into constructing and regulating dual-channel TADF-RTP emission.
• Enables the development of optoelectronic devices with tailored emission characteristics.