A new synthetic strategy toward novel linear two-dimensional graphene nanoribbons up to 12 nm has been established. The nanoribbons are characterized by MS, UV/vis, and scanning tunneling microscopy (STM). Various microscopic studies of these novel structures showed a high tendency to self-assemble.

Organic field-effect transistors (OFETs) are attracting attention because of their potential application in cheap, large-area, flexible electronic devices, such as bendable displays, complementary circuits, and radio-frequency identification tags (RFID). [1][2][3][4] To this end, polymer semiconductors are particularly well-suited, due to their mechanical flexibility and facile processing. However, OFETs have been hampered by very low charge-carrier mobilities, often less than 0.01 cm 2 V À1 s À1

A method of solvent-free sample preparation is shown to be of universal applicability for matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). Results obtained were compared with those of traditional solvent-based sample preparation for MALDI-MS in order to demonstrate their similarities with respect to accuracy, sensitivity and resolution for polymers such as polystyrene and poly(methyl methacrylate) in a mass range from 2 to 100 kDa. The results revealed that there is fundamentally no difference in the quality of the obtained mass spectra, and we conclude that the mechanism of desorption and ionization remains unchanged. However, the solvent-free sample preparation turned out to have some advantages over the traditional method in certain cases: quick and easy applicability is shown for polyetherimide avoiding time-consuming optimization procedures. In particular, industrial pigments that are insoluble in common solvents were characterized without interfering signals from fragments. The method even showed improvements with respect to reproducibility and mass discrimination effects in comparison to traditional sample preparation. Additionally, this contribution provides new insight regarding the analyte/matrix preorganization for the desorption step which now appears to be independent of crystallinity.

The processability of giant (macro)molecules into ultrapure and highly ordered structures at surfaces is of fundamental importance for studying chemical, physical and biological phenomena, as well as their exploitation as active units in the fabrication of hybrid devices. The possibility of handling larger and larger molecules provides access to increasingly complex functions. Unfortunately, larger molecules commonly imply lower processability due to either their low solubility in liquid media or the occurrence of thermal cracking during vacuum sublimation. The search for novel strategies to process and characterize giant building blocks is therefore a crucial goal in materials science. Here we describe a new general route to process, at surfaces, extraordinarily large molecules, that is, synthetic nanographenes, into ultrapure crystalline architectures. Our method relies on the soft-landing of ions generated by solvent-free matrix-assisted laser desorption/ionization (MALDI). The nanographenes are transferred to the gas phase, purified and adsorbed at surfaces. Scanning tunnelling microscopy reveals the formation of ordered nanoscale semiconducting supramolecular architectures. The unique flexibility of this approach allows the growth of ultrapure crystalline films of various systems, including organic, inorganic and biological molecules, and therefore it can be of interest for technological applications in the fields of electronics, (bio)catalysis and nanomedicine.

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