Increase the molecular length and donor strength to boost horizontal dipole orientation for high-efficiency OLEDs. Issue 24 (15th June 2022)

• Record Type: Journal Article
• Authors: Chen, Yi-Kuan; Jayakumar, Jayachandran; Ko, Chang-Lun; Hung, Wen-Yi; Wu, Tien-Lin; Cheng, Chien-Hong
• Is Part Of: Journal of materials chemistry. Volume 10:Issue 24(2022)
• Page Start: 9241
• Page End: 9248
• Publication Date: 2022-06-15
• Subjects: Materials -- Periodicals; Chemistry, Analytic -- Periodicals; Optical materials -- Research -- Periodicals; Electronics -- Materials -- Research -- Periodicals; 543.0284
• DOI: 10.1039/d2tc01435a
• Languages: English
• ISSNs: 2050-7526

Abstract

Abstract : Three pyridine-carbonitrile (PPC) fluorophores with amine-type donors, carbazole, tert -butylcarbazole, and spiroacridine have been designed and synthesized. A high-performance green OLED based on SAcmPPC dopant exhibited an external quantum efficiency of 37.2%. Abstract : Three pyridine-carbonitrile (PPC) fluorophores with amine-type donors, carbazole, tert -butylcarbazole, and spiroacridine have been designed and synthesized. These PPC-based emitters exhibit excellent photoluminescence quantum yields of 92–100%, thermally activated delayed fluorescence (TADF) and thermal stability. More importantly, with increasing molecular lengths via donor modification strategy, it fulfills the aim to rise the horizontal dipole orientation ratios from 76% to 83%. Remarkably, a high-performance green OLED based on spiroacidine-PPC dopant exhibited an external quantum efficiency of 37.2%, a current efficiency of 123.5 cd A −1 and a power efficiency of 121.3 lm W −1 with a relative low driving voltage, only 2.9 V.