Synthesis of Thieno[3,4-b]pyrazine-based Alternating Conjugated Polymers via Direct Arylation for Near-infrared OLED Applications

• DOI: 10.1007/s10118-022-2661-0
• Publication Date: 2022-01-17T12:02:53Z
• Authors: Ze-Wang He; Qiang Zhang; Chen-Xi Li; Hong-Ting Han; Yan Lu
• Keywords: 01 natural sciences; 0104 chemical sciences

Three alternating conjugated polymers, namely PFTP, PCzTP, and PSiTP, which combine a thieno[3,4-b]pyrazine (TP) unit with different benzene-based donor units such as 9,9-dioctylfluorene, 9-heptadecyl-9H-carbazole and 5,5-dioctyl-5H-dibenzo[b,d]silole, were synthesized in good yield (> 85%) and high molecular weight up to Mn = 58 200 via direct arylation polymerization (DArP). All resultant polymers exhibit moderate bandgap of about 1.80 eV and strong deep red/near-infrared emitting in the solid state. Among them, the PSiTP-based electroluminescence (EL) devices with an architecture of ITO/PEDOT:PSS/PTAA/emitting layer/TPBi/LiF/Al give the best performance with a maximum luminance of 2543 cd/m2 at 478 mA/cm2. This work expands the application scope of high-performance conjugated polymers that can be synthesized by DArP.