Organic field-effect transistors based on Langmuir-Blodgett films of an extended porphyrin analogue - Cyclo[6]pyrrole

Field-effect transistors using cyclo[6]pyrrole as active layers were prepared by Langmuir-Blodgett (LB) method. Cyclo[6]pyrrole is a porphyrin analogue with an extended π-system(22-π-electron). It could form a stable, reproducible monolayer at the air-water interface, which could be transferred onto a substrate with nearly unity transfer ratio and resulted in multilayer structure with the cyclo[6]pyrrole molecules stacking in a face-to-face configuration due to strong intermolecular π-π interactions. An un-optimized device based on this LB films displayed a mobility of 0.014 cm2 V−1 s−1, which is higher than the highest value of the devices based on typical porphyrins reported.