Large-Size Single-Crystal Oligothiophene-Based Monolayers for Field-Effect Transistorsстатья
Статья опубликована в высокорейтинговом журнале
Информация о цитировании статьи получена из
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Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 19 марта 2019 г.
Аннотация:High structural quality of crystalline organic semiconductors is the basis of their superior electrical performance. Recent progress in quasi two-dimensional (2D) ultrathin organic semiconductor films challenges bulk single crystals as both demonstrate competing charge carrier mobilities. As the thinnest molecular semiconductors, monolayers offer numerous advantages such as unmatched flexibility and light transparency as well is an excellent platform for sensing. Oligothiophene-based materials are among the most promising for light-emitting applications due to combination of efficient luminescence and decent charge carrier mobility. Here we demonstrate single-crystal monolayers of unprecedented structural order grown from four alkyl-substituted thiophene and thiophene-phenylene oligomers. The monolayer crystals with lateral dimensions up to 3 mm were grown from solution on substrates with various surface energies and roughness by drop or spin casting with subsequent slow solvent evaporation. Our data indicate that 2D crystallization resulting in single-crystal monolayers occur at the receding gas-solution-substrate contact line. The structural properties of the monolayers were studied by grazing-incidence X-ray diffraction/reflectivity, atomic force and differential interference contrast microscopies and imaging spectroscopic ellipsometry. These highly ordered monolayers demonstrated excellent performance in organic field-effect transistors approaching the best values reported for the thiophene or thiophene-phenylene oligomers. Our findings pave the way to efficient monolayer organic electronics highlighting the high potential of simple solution-processing techniques for growth of large-size single-crystal monolayers with excellent structural order and electrical performance competing against bulk single crystals.