Highly Efficient Sky-Blue π-Stacked Thermally Activated Delayed Fluorescence Emitter with Multi-Stimulus Response...

Area of Science:

• Materials Science
• Organic Chemistry
• Optoelectronics

Background:

• Organic materials with multi-stimulus response (MSR) properties are crucial for advanced applications.
• Thermally activated delayed fluorescence (TADF) materials offer efficient light emission.

Purpose of the Study:

• To design and synthesize a novel π-stacked TADF material with MSR properties.
• To investigate the photophysical properties and device performance of the new material.

Main Methods:

• Synthesis of a π-stacked TADF material (SDMAC) using a distorted acridine donor.
• Characterization of MSR properties including aggregation-induced emission enhancement (AIEE), solvatochromism, and piezochromism.
• Fabrication and testing of circularly polarized organic light-emitting diodes (CP-OLEDs) using SDMAC as an emitter.

Main Results:

• SDMAC exhibits a rigid π-stacked configuration with intramolecular through-space interactions.
• The material demonstrates AIEE, solvatochromic, piezochromic, and circularly polarized luminescence (CPL) properties.
• The fabricated CP-OLEDs achieved a maximum external quantum efficiency (EQE) of 28.4%, representing the most efficient CP-TADF OLEDs via through-space charge transfer.
• CP-OLEDs successfully exhibited circularly polarized electroluminescence (CPEL) signals.

Conclusions:

• SDMAC is a highly efficient MSR material with promising TADF properties.
• The developed CP-OLEDs show excellent performance and potential for display and lighting applications.
• The through-space charge transfer strategy is effective for developing high-performance CP-TADF OLEDs.