Acridine Based Small Molecular Hole Transport Type Materials for Phosphorescent OLED Application

Two small molecular hole-transporting type materials, namely 4-(9,9-dimethylacridin-10(9H)-yl)-N-(4-(9,9-dimethylacridin-10(9H)-yl)phenyl)-N-phenylaniline (TPA-2ACR) and 10,10′-(9-phenyl-9H-carbazole-3,6-diyl)bis(9,9-dimethyl-9,10-dihydroacridine) (PhCAR-2ACR), were designed and synthesized using a single-step Buchwald–Hartwig amination between the dimethyl acridine and triphenylamine or carbazole moieties. Both materials showed high thermal decomposition temperatures of 402 and 422 °C at 5% weight reduction for PhCAR-2ACR and TPA-2ACR, respectively. TPA-2ACR as hole-transporting material exhibited excellent current, power, and external quantum efficiencies of 55.74 cd/A, 29.28 lm/W and 21.59%, respectively. The achieved device efficiencies are much better than that of the referenced similar, 1,1-Bis[(di-4-tolylamino)phenyl]cyclohexane (TAPC)-based device (32.53 cd/A, 18.58 lm/W and 10.6%). Moreover, phenyl carbazole-based PhCAR-2ACR showed good device characteristics when applied for host material in phosphorescent OLEDs.

Novel Anthracene HTM Containing TIPs for Perovskite Solar Cells

Recently, perovskite solar cells have been in the spotlight due to several of their advantages. Among the components of PSCs, hole transporting materials (HTMs) re the most important factors for achieving high performance and a stable device. Here, we introduce a new D–π–D type hole transporting material incorporating Tips-anthracene as a π–conjugation part and dimethoxy-triphenylamine as a donor part (which can be easily synthesized using commercially available materials). Through the measurement of various optical properties, the new HTM not only has an appropriate energy level but also has excellent hole transport capability. The device with PEH-16 has a photovoltaic conversion efficiency of 17.1% under standard one sun illumination with negligible hysteresis, which can be compared to a device using Spiro_OMeTAD under the same conditions. Ambient stability for 1200 h shown that 98% of PEH-16 device from the initial PCE was retained, indicating that the devices had good long-term stability.