Highly efficient green phosphorescent organic light-emitting diodes based on tetraphenyl silicon derivative host materials

Regulation of excited-state properties of dibenzothiophene-based fluorophores for realizing efficient deep-blue and HLCT-sensitized OLEDs

“…Moreover, the heavy atom effect of sulfur can enhance the spin-orbit coupling (SOC), which can effectively modulate the intersystem crossing (ISC) and reversed intersystem crossing (RISC) processes. However, most of the reported DBT derivatives were used as the host for phosphorescent and TADF dopants [16][17][18][19][20][21][22][23][24][25][26][27] and connected with acceptor or donor units to construct electron-or holetransporting materials, [28][29][30] and only a few of them were used as yellow, green, and blue emitters in OLEDs. 26,31,32 For example, Guo et al developed a series of green and yellow TADF emitters with DBT as a donor unit, achieving high EQEs of over 9% in the non-doped devices.…”

High-performance blue OLED using multiresonance thermally activated delayed fluorescence host materials containing silicon atoms

“…The presence of TPS moieties thus enables the formation of amorphous thin films and leads to high thermal stability because the materials have relatively high molecular weights. The substitution of the TPS moiety itself has been reported to result in a high triplet energy level but also lower electron transport ability [17][18][19] . However, in the case of the DOBNA structure, the electron-transport ability can be improved because the boron atom containing an empty p orbital induces an electron-withdrawing effect in the p z -π junction 10 .…”