Achieving High Efficiency at High Luminance in Fluorescent Organic Light‐Emitting Diodes through Triplet–Triplet Fusion Based on Phenanthroimidazole‐Benzothiadiazole Derivatives. Issue 55 (21st August 2021)

• Record Type: Journal Article
• Authors: Tang, Xiangyang; Liu, Hui; Xu, Lei; Xu, Xuehui; He, Xin; Liu, Futong; Chen, Jianwu; Peng, Qiming
• Is Part Of: Chemistry. Volume 27:Issue 55(2021)
• Page Start: 13828
• Page End: 13839
• Publication Date: 2021-08-21
• Subjects: benzothiadiazole -- efficiency roll-off -- organic light-emitting diodes -- phenanthroimidazole -- triplet–triplet fusion; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.202102136
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: Achieving high efficiency at high luminance is one of the most important prerequisites towards practical application of any kind of light‐emitting diode (LED). Herein, we report highly emissive organic fluorescent molecules based on phenanthroimidazole‐benzothiadiazole derivatives capable of maintaining high external quantum efficiency (EQE) at high luminance enabled by triplet–triplet fusion (TTF) in doped organic LEDs. The PIBzP‐, PIBzPCN‐, and PIBzTPA‐based devices showed EQEs of 8.27, 9.15, and 8.64 %, respectively, at luminance of higher than 1000 cd m −2, with little efficiency roll‐off. Abstract : On a high : A series of phenanthroimidazole‐benzothiadiazole‐based fluorescent donor–acceptor molecules were designed and synthesized. They exhibited emissions ranging from green to red with high photoluminescence quantum yield in the solid state. These molecules also showed highly efficient electroluminescence at high luminance enabled by triplet–triplet fusion.