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Novel pincer-type, pyridine-bridged bis(benzimidazolylidene)-palladium complexes 5-7 were synthesised from cheap commercial precursors under microwave assistance. Although simple in structure, carbene complexes 5a,b are efficient low-molecular-mass metallogelators. They gelate not only a broad variety of protic and aprotic organic solvents, but also different types of customary ionic liquids (such as imidazolium, pyridinium, pyrazolidinium, piperidinium and ammonium salts) at concentrations as low as 0.5 mg mL(-1). The morphologies of the resulting 3D gel networks composed from long and thin fibres were studied by TEM and light microscopy for a selection of organic and ionic liquids. The achiral gelators are able to induce the formation of helical fibres. The thermal stability of the gel samples increases with the gelator concentration as demonstrated by thermoreversible DSC studies. Temperature-dependent NMR and X-ray diffraction studies, as well as comparisons with pincer complex analogues bearing shorter alkyl chains, suggest that the 3D networks responsible for gelation are based on non-covalent interactions, such as pi-stacking, van der Waals interactions, and hydrogen and metal-metal bonding. Ionic liquids and gels obtained from them and 5a,b display comparable high conductivities, which characterises pyridine-bridged bis(benzimidazolylidene)-palladium pincer complexes as air-stable metallo gelators that efficiently immobilise ionic liquids in low gelator concentration indicating--beyond catalysis--their potential applications in electrochemical devices.

Lieber etwas größer: Der Protonentransfer im elektronischen Grundzustand von (C6H5NH−)⋅(H2O)n wurde photoelektronenspektroskopisch untersucht. Bei n=3 wird ein Proton eines Wassermoleküls durch das deprotonierte Anilin unter Bildung von solvatisiertem OH− abgespalten (siehe Bild). Diese Beobachtungen werden durch Ab‐initio‐Rechnungen gestützt, die für n≥3 die größere Stabilität der solvatisierten OH−‐Ionen belegen.

Three-dimensional microbatteries have emerged as a new direction for powering microelectronic devices, where the threedimensional nanostructured electrode is the key component for microbatteries to achieve high power density and high energy density in a small footprint. In this work, we present a novel approach for fabrication of LiCoO 2 nanowire arrays as threedimensional cathode for microbatteries. Mesoporous low-temperature LiCoO 2 nanowire arrays can be directly prepared by a twostep hydrothermal method and they can be easily converted into chain-like high-temperature LiCoO 2 nanowire arrays through further calcination. The layered LiCoO 2 nanowire arrays exhibit both high gravimetric capacity and areal capacity, while maintaining good cycling stability and rate capability. The facile synthesis and superior electrochemical performance of the three-dimensional LiCoO 2 cathode make it promising for application in microbatteries.

The self-assembly of monolayers of thiols on gold(111) surfaces yields substrates that are able to template in a controlled manner, the nucleation and growth of crystals of calcium carbonate from solution. In the absence of additives, various factors such as the nature of the thiol, the temperature, and the pH are now established as influencing the nature and relative amounts of the different CaCO3 phases (calcite, vaterite, and aragonite). Recently, we have been able to extend the use of thiol/gold self-assembled monolayers as templates for the growth of inorganic crystals by utilizing protected gold colloids instead of flat gold surfaces. The thiol monolayers that protect the colloids provide heterogeneous interfaces for the initial nucleation of the inorganic crystal. The utility of such a designer seeding is demonstrated through the crystallization of CaCO3 in the calcite modification and SrCO3 in the strontianite modification.

The size-selective synthesis of hexagonal Sb2Te3 nanoplates by thermal decomposition of the single source precursor bis(diethylstibino)telluride (Et2Sb)2Te is described for the first time. The role of the thermolysis temperature and the concentration of the capping agent (PVP*) on the growth of the nanoplates was investigated. The thermal properties of (Et2Sb)2Te were investigated by differential scanning calorimetry (DSC) and the resulting Sb2Te3 nanoplates were characterized by XRD, SEM, TEM, EDX and SAED. Moreover, electrical conductivity and Seebeck coefficient and thermal conductivity of the nanoplates were determined, clearly proving the enhanced thermoelectric properties of nanosized antimony telluride.

Amorphous ceramics with the chemical composition Si 3 B 3 N 7 and SiBN 3 C were produced from single-source molecular precursors by polymerization and pyrolysis. The powder and fiber materials were investigated by means of energy filtering transmission electron microscopy. The intensity of elastically scattered electrons is recorded to calculate the pair distribution function of these ceramics. In the pair distribution function of Si 3 B 3 N 7 three significant maxima at 0.144, 0.172, and 0.291 nm are clearly resolved and are assigned to the pair distances B-N, Si-N, and Si-Si (N-N), respectively, by comparison to crystalline materials. The predominant structural units of the ceramic are trigonal planar BN 3 and tetrahedral SiN 4 groups, which are close to their regular symmetry. The overall pair distribution function of SiBN 3 C is very similar to that of Si 3 B 3 N 7 ; however, the maxima are broadened due to the incorporation of carbon into the network. High-resolution mapping of the elements Si, B, N, and C with electron spectroscopic imaging reveals a homogeneous distribution on a subnanometer scale without precipitation or separation of, for example, carbon-rich clusters. Similarly, elemental mapping of Si 3 B 3 N 7 reveals a random distribution of the elements Si, B, and N at the same scale. Both new ceramics consist of an amorphous network with bonds and coordinations as preformed in the precursor.