Effect of substituents on the properties of distyrylarylene-based field-effect transistor materials

Two new distyrylarylene derivatives, 4,4′-bis(2-dibenzothienylvinyl)biphenyl (1) and 4,4′-bis(2-bithienylvinyl)biphenyl (2), were synthesized with good yields. Their properties are compared with 4,4′-bis[2-(3-N-butylcarbazolyl)vinyl]biphenyl (3). Our experiments reveal that the substituents have significant effects on the optical behaviors and film morphologies. The OFET properties of these materials were investigated. Both 1 and 2 exhibit hole mobility higher than 0.01 cm2 V−1 s−1 with good environmental stability. However, the devices using 3 as active layer show poor carrier-transporting ability due to weak intermolecular interactions in the film. These results reveal that the substituent has significant effect on the OFET performance of distyrylarylene-based materials.