Hyperfluorescent guest@TADF-MOF Materials for the 5th Generation of OLEDs

Introduction

Organic light emitting diodes (OLEDs) are among the most efficient optoelectronic devices for multiple displays and illumination technologies. Their superior performance over conventional sources has boosted this discipline, reaching what is considered the 4th generation of OLEDs.

Hyperfluorescence Concept

These OLEDs are based on a novel concept known as hyperfluorescence (HF), in which a thermally activated delayed fluorescent (TADF) material acts as a sensitizer of a narrow-band fluorescent emitter via Förster resonance energy transfer (FRET). However, HF-OLEDs still present intrinsic limitations mostly related to molecular aggregation of TADF compounds and the FRET efficiency.

Role of Metal-Organic Frameworks

Metal-organic frameworks (MOFs) are excellent platforms for developing novel HF materials to be used in the fabrication of more efficient OLEDs. Their ordered structure, combined with the possibility of using TADF molecules as organic linkers, will minimize the issues associated with molecular aggregation while enhancing the TADF mechanism by reducing molecular motions.

Advantages of MOFs

Moreover, their porous structure allows for the encapsulation of narrow-band emitters (HF guest@TADF-MOFs), shortening the distances between the donor (TADF-MOF) and the acceptor (narrow-band emitter), and thus, increasing the FRET efficiency.

Project Objectives

HyperFMOF intends to fabricate and fully characterize novel HF guest@TADF-MOFs, which will be subsequently integrated as emissive layers of high-performance OLEDs. This project is multidisciplinary and highly ambitious, and the overall aim will be achieved by:

1. The synthesis and characterization of unexplored TADF linkers, TADF-MOFs, and HF guest@TADF-MOFs.
2. The in-depth investigation of their spectroscopic and photodynamic properties.
3. The manufacturing, characterization, and optimization of novel HF guest@TADF OLEDs.

Impact

HyperFMOF will open new avenues in different research areas from synthesis to spectroscopy and OLED technology, and will overcome the limitations of preceding OLED generations.