Chemically doped hole transporting materials with low cross-linking temperature and high mobility for solution-processed green/red PHOLEDs

Recent advances of crosslinkable organic semiconductors in achieving solution-processed and stable optoelectronic devices

“…To solve this issue, Wang et al reported a method combining UV light and heating to lower the crosslinking temperature. 143 Specifically, they designed two crosslinkable HTLs with vinyl units, namely V-TPAVTPD and V-TPAVCBP. Meanwhile, 4-octyloxydiphenyliodonium hexafluoroantimonate (OPPI) as a cationic photoinitiator was added into the crosslinkable HTL for lowering the crosslinking condition and improving hole mobility.…”

Suppressing triplet exciton quenching by regulating the triplet energy of crosslinkable hole transport materials for efficient solution-processed TADF OLEDs

“…Here, OPPI was doped into the crosslinked HTL to confine the ionic compound to the crosslinked network (Fig. S15) [35]. OPPI is a cationic photoinitiator, which can trigger the styrene group for crosslinking reaction and lower the crosslinking temperature under UV light irradiation.…”

“…OPPI is a cationic photoinitiator, which can trigger the styrene group for crosslinking reaction and lower the crosslinking temperature under UV light irradiation. Besides, the HSbF 6 generated after the photoinitiation of OPPI can oxidize triphenylamine to form triphenylamine cation radicals [35], improving the hole mobility of the HTL. The hole mobilities of the doped V-p-DBT and V-p-DBF were 2.2 × 10 −3 and 3.9 × 10 −3 cm 2 V −1 s −1 (Fig.…”

Construction of a fully conjugated cross-linked hole-transport film based on ethynyl to enable high mobility for efficient solution-processed OLEDs

“…The current efficiency (CE) of the green phosphorescent OLED (PHOLED) at 1000 cd m −2 was increased to 51.9 cd A −1 compared with 45.9 cd A −1 of VPEC. Wang et al 34 synthesized V-TPAVTPD and V-TPAVCBP based on the triarylamine structure by the introduction of vinyl bridging groups within the molecule to expand molecular conjugation. Their mobility reached up to 1.1 × 10 −4 and 5.5 × 10 −5 cm 2 V −1 s −1 , respectively.…”