Donor-Spiro-Acceptor Molecular Design: A Key Towards High-Efficiency Simplified Single-Layer Phosphorescent Organic Light-Emitting Diodes - Université de Rennes Accéder directement au contenu
Article Dans Une Revue Accounts of Materials Research Année : 2023

Donor-Spiro-Acceptor Molecular Design: A Key Towards High-Efficiency Simplified Single-Layer Phosphorescent Organic Light-Emitting Diodes

Résumé

In organic electronic technologies, Single-Layer Phosphorescent Organic Light-Emitting Diodes (SL-PhOLEDs), only made of the electrodes and the Emissive Layer (EML), are a new generation of simplified PhOLEDs. In the field of OLED, such a type of devices has been studied for a long time as they represent 'ideal' devices. Indeed, simplifying the classical multi-layers structure of PhOLEDs (called ML-PhOLEDs) is important to reduce the amount of commodities, the manufacture complexity, the production and recycling costs. However, removing the functional organic blocking/transporting layers of a ML-PhOLED stack leads to an intense decrease of the PhOLED performance. This is the main problem; the researchers have faced in this field. To keep a high performance without the different organic layers, the effective injection, transport and recombination of charges in the device, should be performed by the EML and more particularly by the host materials. This host material should then display a set of electronic and physical properties, essential to reach a high-efficiency SL-PhOLED. However, reaching high performance SL-PhOLED is far more difficult than for ML-PhOLED and each molecular parameter of the host can dramatically decreases the PhOLED performance. The molecular design of the host is then crucial and a specific design has been particularly studied in the last years, which consists to link an electron-rich unit to an electron-poor unit via a spiro linkage. This design called Donor-Spiro-Acceptor (D-Spiro-A) allows to gather all the required properties in a single host and has allowed, these last years, important advances in the field. Nowadays, the most efficient SL-PhOLEDs use this molecular design and our group has particularly contributed to this research field. Thus, as the D-Spiro-A molecular design nowadays provides SL-PhOLEDs with the highest performance, well understanding its impact in the device efficiencies appears particularly important. This is the story we want to tell herein. In this account, we discuss through a structure/properties/device performance relationship study (triplet state energy level, HOMO/LUMO energy levels, charge carriers mobilities, thermal and morphological properties and device performances), the recent advances made by this design in the field of SL-PhOLEDs. This account will mainly focus on the association of phenylacridine-like fragments (namely phenylacridine, indoloacridine, quinolinophenothiazine and quinolinoacridine) as electron rich unit and fluorene/phosphine oxide as electron-poor unit, which is, in the light of the literature, the combination, which has allowed the most important advances in the last years. Trying to unravel why this design has led to high performance, appears to be important for the future of SL-PhOLED technology, and may lead to new directions in term of molecular design.

Domaines

Chimie
Fichier principal
Vignette du fichier
AMR 2023 REVISED.pdf (1.55 Mo) Télécharger le fichier
Origine Fichiers produits par l'(les) auteur(s)

Dates et versions

hal-04208613 , version 1 (15-09-2023)

Identifiants

Citer

Cyril Poriel, Joëlle Rault-Berthelot. Donor-Spiro-Acceptor Molecular Design: A Key Towards High-Efficiency Simplified Single-Layer Phosphorescent Organic Light-Emitting Diodes. Accounts of Materials Research, 2023, 4 (9), pp.733-745. ⟨10.1021/accountsmr.3c00078⟩. ⟨hal-04208613⟩
21 Consultations
21 Téléchargements

Altmetric

Partager

Gmail Mastodon Facebook X LinkedIn More