Hydrogen-Bond-Directed Supramolecular Organic Semiconductor Thin Films Realized via Thermal Precursor Approach

Flexible organic semiconductors are regarded as an important class of functional materials, enabling their fabrication via a solution-processed method. However, supramolecularly designed organic thin-film transistor (OTFT) devices using hydrogen bonds have not been sufficiently developed. This is because of the reduced solubility caused by introducing hydrogen bond sites and the difficulty in controlling molecular orientations and packing structures. Herein, we report a reasonable strategy for the formation of hydrogen-bonded semiconductor thin films of a tetrabenzoporphyrin derivative with amide groups using the thermal precursor approach. The thin films are successfully fabricated by thermal conversion of the corresponding precursor in the film state. Assembly structure with a hydrogen-bond network is revealed by the combination of X-ray diffraction and infrared p-polarized multiple-angle incidence resolution spectrometry. The OTFT devices exhibit high hole mobility of 0.25 cm² V^-1 s^-1 among hydrogen-bonded OTFTs reported previously. Notably, we unveiled the high thermal stability of semiconductor films without decreasing device performance in air up to 250 °C. This strategy can become a key methodology to form hydrogen-bond-directed organic electronic devices, namely supramolecular devices.