A Multifunctional Molecular System for Solution-Processed Organic Light-Emitting Diodes

2016 Fiscal Year Final Research Report

• Project/Area Number: 15H06470
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Single-year Grants
• Research Field: Device related chemistry
• Research Institution: Kyushu University
• Principal Investigator: Aizawa Naoya 九州大学, 稲盛フロンティア研究センター, 特任助教 (60754918)
• Project Period (FY): 2015-08-28 – 2017-03-31
• Keywords: 有機EL / 塗布 / 励起子 / エネルギー移動 / デンドリマー

Outline of Final Research Achievements

Organic semiconductors exhibiting thermally activated delayed fluorescence (TADF) have energetically equivalent spin-singlet and spin-triplet excited states. In the presence of an energy acceptor, each of the excited states undergoes energy transfer on different length scales. However, a lack of quantitative scaling parameters that affect energy transfer rates hampers the rational molecular design to control exciton transport in organic light-emitting diodes (OLEDs) using TADF. Here we report a dendritic fluorophore G1, which consists of an anthracene-based core encapsulated by four insulating tris(4-tert-butylphenyl)methyl groups. By using a combination of transient photoluminescence decay measurements and kinetic modeling, we examine spin-dependent energy transfer in blended films of a TADF emitter and G1, revealing that the encapsulated structure effectively inhibits triplet excitons from funneling to the core fluorophore and thus improves internal quantum efficiencies.

Free Research Field

有機エレクトロニクス