Furan-Containing Quinoidal Compounds for High-Performance Copper/Silver Electrode-Based n-Channel Organic Transistors

Furan-containing quinoidal compounds FTzTzF-C10 and FTzTzF-C8 were synthesized. These compounds have low lowest unoccupied molecular orbital (LUMO) energy levels and can form a charge transfer complex with Ag and Cu films, proved by cyclic voltammograms and Raman spectra. Single crystal diffraction results reveal that they adopt a lamellar layer structure with strong π–π interactions in crystals. Thin film transistor characterization shows that FTzTzF-C10 and FTzTzF-C8 exhibit n-channel behavior with an electron mobility of 1.18 cm2 V–1 s–1, one of the highest electron mobilities reported for thin film devices based on furan-containing semiconductors. Notably, the performance of FTzTzF-C10 and FTzTzF-C8 devices is nearly independent of the metals (Au, Cu, and Ag) of source–drain electrodes, which is ascribed to the ultrathin charge transfer layer formed by the spontaneous reaction of FTzTzFs and electrodes (Ag, Cu). These results demonstrate that furan is an excellent block for quinoidal semiconductors and promote the development of Cu/Ag electrode-based organic transistors.