| 초록 |
Nanostructures of P3HT series in spun-cast films were changed from rods, fibrils to less-ordered granules as Mw increased. Electrical properties of the cast films in organic field-effect transistors (OFETs) supported that the π-conjugated junction between the crystals plays an important role in yielding better charge transport, as well as the intra- and inter-molecular π-conjugation of the chains. In the spun-cast films, percolated nanorods of P3HTs (Mw ＜ 13 kDa) showed poor mobility (μFET) values less than 0.001 cm2V-1s-1 in OFETs, while long conjugated fibrils of the relatively high Mw P3HTs improved the μFET values up to 0.04 cm2V-1s-1. Interestingly, it was found that different types of P3HT crystallites could be directly developed on gate dielectrics via spin-casting of previously ultrasonicated 0.1-0.2 wt% P3HT solutions: two-dimensional nanosheet and one-dimensional nanofibril, depending on the Mw of P3HTs. |
