In:
Journal of Materials Chemistry C, Royal Society of Chemistry (RSC), Vol. 10, No. 42 ( 2022), p. 15981-15988
Abstract:
The development of solution-processable pure-red thermally activated delayed fluorescence (TADF) emitters remains a challenging task in the field of organic light-emitting diodes (OLEDs). Here two strong electron acceptor moieties, acenaphtho[1,2- b ][1,2,5] oxadiazolo[3,4- e ]pyrazine (ANOP) and acenaphtho[1,2- b ][1,2,5] thiadiazolo[3,4- e ]pyrazine (ANTP), were designed and synthesized by fusing 1,2,5-oxadiazole or 1,2,5-thiadiazole on an acenaphtho[1,2- b ]pyrazine unit through a simple and catalyst-free dehydration cyclization reaction. Combined with rigid electron-donating units, 9,9-dimethyl-9,10-dihydroacridine (DMAC) and 2,7-dimethyl-10 H spiro[acridine-9,9′-fluorene] (MeFAC), four solution-processable pure-red TADF emitters, ANOP-DMAC, ANOP-MeFAC, ANTP-DMAC, and ANTP-MeFAC, were designed and prepared through catalyst-free nucleophilic substitution reactions. The rational molecular design principles endow all the emitters with small singlet-triplet energy gaps (Δ E ST ), prominent TADF character, red emission, and moderate Φ PL s. The optical, electrochemical, and film morphological properties of all the emitters were systematically investigated. As a consequence, the ANTP-DMAC-based OLED realized a maximum external quantum efficiency of 6.8% with a peak wavelength at 630 nm and Commission International de l’Eclairage 1931 (CIE1931) coordinates of (0.59, 0.40), which is among one of the highest device performances for solution-processed pure-red TADF OLEDs.
Type of Medium:
Online Resource
ISSN:
2050-7526
,
2050-7534
Language:
English
Publisher:
Royal Society of Chemistry (RSC)
Publication Date:
2022
detail.hit.zdb_id:
2702245-6
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