Template-Assisted Assembly of DPP-TTT over a Hydrophilic Liquid Subphase toward Enhanced Charge Transport in Organic Field-Effect Transistors

The progress in flexible electronics significantly benefits from improvements in charge transport within organic field-effect transistors (OFETs). The techniques used to incorporate organic conjugated polymers (CPs) into devices greatly influence their performance. In this study, we introduce an innovative method that utilizes the flexibility and solution-processing capabilities of donor–acceptor (D–A) type CPs, combined with the electrical conductivity and durability of two-dimensional (2D) organic materials in a composite mixture. Furthermore, during the production of thin films via the “unidirectional floating film transfer method (UFTM)”, it was observed that 2D organic C3N5 nanosheets enhance the organization of the D–A polymer, poly[2,5-(2-octyl-dodecyl)-3,6-diketopyrrolopyrrole-alt-5,5-(2,5-di(thien-2-yl) thieno[3,2-b] thiophene)] (DPP-TTT), on a hydrophilic liquid base, acting as a structural scaffold. This approach promotes the development of well-ordered DPP-TTT arrays, improving π–π stacking and intermolecular forces, which are essential for efficient charge transport. The OFETs crafted using this technique show a remarkable increase in charge carrier mobility, up to 0.41 cm2/(V s), with on/off ratios of 104 and superior operational durability. Our findings highlight the effectiveness of scaffold-assisted assembly on a liquid phase and the combined benefits of D–A polymers with 2D organic materials, offering a powerful approach for creating organic semiconductors with enhanced electrical characteristics. This opens promising pathways for advancing high-performance flexible electronic devices.