We report the molecular design and synthesis of a novel selenium-containing multi-resonance thermally activated delayed fluorescence (MR-TADF) host material, 3,6-di-tert-butyl-9,16-dioxa-15-selena-4b-boraindeno[2,1-a]naphtho[3,2,1-de]anthracene (TDBA-SePh), for green and red phosphorescent organic light-emitting diodes (PhOLEDs). By incorporating selenium into the DOBNA-based MR-TADF backbone, the reverse intersystem crossing (RISC) process was effectively activated, leading to enhanced utilization of triplet excitons. The corresponding RISC rate was determined to be 3.91 × 10⁴ s⁻¹. When applied to PhOLED devices, TDBA-SePh-based green and red OLEDs exhibited higher external quantum efficiency (EQE) and reduced efficiency roll-off compared to conventional mCP-based host materials. At a luminance of 1000 cd m⁻², the green and red devices exhibited roll-off values of 2.5% and 4.3%, respectively. This improvement is attributed to the incorporation of selenium as a heteroatom, which accelerates the RISC process, thereby suppressing triplet-triplet annihilation (TTA). These results suggest that adopting a similar molecular design strategy can not only reduce efficiency roll-off but also enhance device efficiency and operational stability, offering significant potential for future OLED applications.

To develop antistatic materials suitable for semiconductor wafer transportation trays, in situ polymerized polystyrene (PS) and polyester (PETE) materials incorporating multi-walled carbon nanotubes (MWNTs) were synthesized. Their thermal and electrical properties were evaluated under conditions relevant to semiconductor tray manufacturing. Both the PS and PETE materials exhibited improved thermal stability with an increasing MWNT content. Differential scanning calorimetry (DSC) revealed that the glass transition temperature (T_g) of the PS increased from 82 °C (0 wt%) to 86 °C (1.0 wt%) and 91 °C (2.0 wt%), while that of the PETE increased from 83 °C to 84 °C and 90 °C, respectively. Surface resistivity measurements also demonstrated enhanced electrical conductivity. For the PS, resistivity decreased from >10¹³ Ohm/sq to 8.8 × 10³ and 3.7 × 10³ Ohm/sq at 1.0 wt% and 2.0 wt% MWNT, respectively. The PETE materials followed a similar trend, with values dropping from >10¹³ Ohm/sq to 5.9 × 10³ and 0.2 × 10³ Ohm/sq. These results confirm that MWNT incorporation effectively enhances both thermal and electrical performance, demonstrating the potential of MWNT/PS and MWNT/PETE as antistatic materials for semiconductor applications.

Two blue fluorescent dopants were designed and successfully synthesized, 5-(2,12-di-tert-butyl-5,9-dioxa-13b-boranaphtho [3,2,1-de]anthracen-7-yl)-5H-benzo[b]carbazole (TDBA-Bz) and 9-(2,12-di-tert-butyl-5,9-dioxa-13b-boranaphtho[3,2,1-de]anthracen-7-yl)-9H-carbazole (TDBA-Cz). Both in solution and the film state, the two emitters demonstrated deep-blue luminescence characteristics. In solution-processed organic light-emitting diodes (OLEDs), TDBA-Bz and TDBA-Cz used as dopant materials showed electroluminescence peaks at 436 nm and 413 nm, respectively. The corresponding CIE color coordinates were determined to be (0.181, 0.114) for TDBA-Bz and (0.167, 0.086) for TDBA-Cz. The solution-processed device using TDBA-Cz as a dopant exhibited a current efficiency (CE) of 7.25 cd/A and an external quantum efficiency (EQE) of 6.45%, demonstrating higher efficiencies compared to the device with TDBA-Bz. In particular, at a luminance of 2000 cd/m², TDBA-Cz maintained an EQE of 4.81%, with only a slight decrease from its maximum EQE.