Recent work has shown the potential of ionic liquids (ILs) as a precursor for porous networks and nitrogen doped carbon materials. The combination of liquid state and negligible vapour pressure represents almost ideal precursor properties and simplifies the processing drastically. Here, we extend this work to get a deeper insight into the solid formation mechanism and to synthesize a mixed boron carbon nitride species by the thermolysis of N,N 0-ethylmethylimidazolium tetracyanoborate (EMIMTCB), a well-known boron- and nitrogen-containing IL. In contrast to other molecule pyrolysis routes boron carbon nitride shows the average composition ‘‘BC3N’’ and like other IL-derived materials turns out to be distorted graphitic, but thermally and chemically very stable, and possesses favourable electrical properties. The detailed mechanistic investigation using TG-IR, FT-IR, solid-state NMR, Raman, WAXS, EELS, XPS and HRTEM also contributes to the general understanding of IL-based material formation mechanisms

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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.

ZnO is a promising n-type oxide thermoelectric material, which is stable in air at elevated temperatures. In the present study we report the bottom-up approach to create Al-doped ZnO nanocomposites from nanopowders, which are prepared by chemical vapour synthesis. With our synthesis route we are able to create highly doped Al-containing ZnO nanocomposites that exhibit bulk like electrical conductivity. Concurrently, the impact of microstructure of nanocomposites on their thermal conductivity is enormous with a value of 1.0 W/mK for 1%Al-ZnO at room temperature, which is one of the lowest values reported so far on ZnO nanocomposites. The optimization of the Al-doping and microstructure with respect to the transport properties of bulk Al-ZnO nanocomposites leads to a zT value of about 0.24 at 950 K, underlining the potential of our technique.

It is shown that current-activated pressure-assisted densification (CAPAD) is sensitive to the Peltier effect. Under CAPAD, the Peltier effect leads to a significant redistribution of heat within the sample during the densification. The densification of highly p-doped silicon nanoparticles during CAPAD and the properties of the obtained samples are investigated experimentally and by computer simulation. Both, simulation and experiments, indicate clearly a higher temperature on the cathode side and a decreasing temperature from the center to the outer shell. Furthermore, computer simulations provide additional insights into the temperature profile which explain the anisotropic properties of the measured sample.