Photocrosslinkable π-conjugated cruciform molecules for electronic/ optoelectronic applications

The development of organic field-effect transistors (OFETs) and organic photovoltaic cells (OPV) has seen much progress using solution-processable organic semiconductors, which can combine high charge transport mobility, stability and patternability. In this work, we report on the design and synthesis of a new type of photopatternable n -conjugated cruciform molecule. These molecules are capable of photopatterning by virtue of photopolymerization of the reactive end-groups (pentadien or acrylate). Their solubility is very good for solution processing. Transistor devices using these molecules provided a maximum field-effect mobility of 3.7 x 10-3 cm2 V-1 s-1 as well as a high current on/off ratio. Remarkably, it was found that their charge carrier mobilities were well-maintained, even after the photocrosslinking process.