Final Report Summary - ORGELNANOCARBMATER (A Universal Supramolecular Approach toward Organic Electronic Materials and Nanostructured Carbonaceous Materials from Molecular Precursors)
The project aimed at developing novel materials for organic electronic applications and nanostructured carbon materials, by combining organic synthesis, polymer science, supramolecular chemistry, materials science, and device fabrication in an integrated and multidisciplinary research approach. Specific targets included the development of a chemical-synthetic approach for functional conjugated molecules, the use of the obtained molecules in the manufacturing of crystalline thin films for organic field-effect transistors, the preparation of semiconducting organic nanowires from related molecules, a chemical-synthetic approach toward novel types of molecular carbon precursors, the investigation of their self-assembly in aqueous dispersion or at the air-water interface, as well as the subsequent carbonization of the aggregates as a pathway toward novel nanostructured carbon materials and carbon-inorganic nano composites.
We have successfully addressed all of these project parts. The major concepts defined in the original project proposal have all proven to be valid and have been applied to the research goals already accomplished. Highlights of technological achievements and examples of novel or unusual methodologies include the following aspects of our research:
(1) We have developed a novel approach for the large-scale synthesis of functional conjugated molecules that solves major technological problems (low solubility, poor processability of organic semiconductors).
(2) The conjugated molecules were processed into thin films with enhanced crystallinity by vapor deposition. The structure of these films was investigated in great detail. Hence, we found that, in the films, the molecular packing was ideally suited for 2D charge transport and, accordingly, organic field-effect transistors (OFETs) exhibited an apparent charge carrier mobility that surpassed the best values ever reported for single-crystalline quaterthiophenes.
(3) We have developed a reliable method to promote the “self-organization” of conjugated molecules into well-defined organic nanowires, that is, semiconducting “cables” formed from a single stack of the moelcules, with defined lateral dimensions on the order of just a few nanometers. These nanowires have, for the first time, allowed us to investigate and describe charge carrier generation and transport in organic semiconductors under nanoscopic confinement. From a detailed structural analysis of such nanowires and microfibers thereof we could prove the importance of including conformational flexibility into the molecular design in order to promote synergistically enhanced hydrogen bonding and π–π stacking between adjacent molecules.
(4) We have developed the first low-temperature synthesis of carbon nanostructures based on unusual, reactive and carbon-rich molecular precursors. The preparation method works at room-temperature or even below in an aqueous environment and produces nanostructured carbon materials with a carbon microstructure otherwise only obtained by processing at temperatures above 800 °C. This allowed us to produce novel carbon nanomaterials and carbon-inorganic composites that may be relevant for several fields of emerging technologies, such as photovoltaics or lithium storage.
In the process, our laboratory has further extended its expertise in synthetic materials chemistry and, in addition, shifted its focus to the characterization of nanostructured organic materials, the preparation of crystalline organic thin films by physical vapor deposition, and the fabrication and characterization of organic electronic devices.
We have successfully addressed all of these project parts. The major concepts defined in the original project proposal have all proven to be valid and have been applied to the research goals already accomplished. Highlights of technological achievements and examples of novel or unusual methodologies include the following aspects of our research:
(1) We have developed a novel approach for the large-scale synthesis of functional conjugated molecules that solves major technological problems (low solubility, poor processability of organic semiconductors).
(2) The conjugated molecules were processed into thin films with enhanced crystallinity by vapor deposition. The structure of these films was investigated in great detail. Hence, we found that, in the films, the molecular packing was ideally suited for 2D charge transport and, accordingly, organic field-effect transistors (OFETs) exhibited an apparent charge carrier mobility that surpassed the best values ever reported for single-crystalline quaterthiophenes.
(3) We have developed a reliable method to promote the “self-organization” of conjugated molecules into well-defined organic nanowires, that is, semiconducting “cables” formed from a single stack of the moelcules, with defined lateral dimensions on the order of just a few nanometers. These nanowires have, for the first time, allowed us to investigate and describe charge carrier generation and transport in organic semiconductors under nanoscopic confinement. From a detailed structural analysis of such nanowires and microfibers thereof we could prove the importance of including conformational flexibility into the molecular design in order to promote synergistically enhanced hydrogen bonding and π–π stacking between adjacent molecules.
(4) We have developed the first low-temperature synthesis of carbon nanostructures based on unusual, reactive and carbon-rich molecular precursors. The preparation method works at room-temperature or even below in an aqueous environment and produces nanostructured carbon materials with a carbon microstructure otherwise only obtained by processing at temperatures above 800 °C. This allowed us to produce novel carbon nanomaterials and carbon-inorganic composites that may be relevant for several fields of emerging technologies, such as photovoltaics or lithium storage.
In the process, our laboratory has further extended its expertise in synthetic materials chemistry and, in addition, shifted its focus to the characterization of nanostructured organic materials, the preparation of crystalline organic thin films by physical vapor deposition, and the fabrication and characterization of organic electronic devices.