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

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.

Silicon based thermoelectrics are promising candidates for high temperature energy scavenging applications. We present the properties of thermoelectrics made from highly boron doped silicon nanoparticles. The particles were produced by a continuous gas phase process in a scaled‐up synthesis plant enabling production rates in the kg h−1 regime. The silicon nanoparticles were compacted by direct current assisted sintering to yield nanocrystalline bulk silicon with average crystallite size between 40 and 80 nm and relative densities above 97% of the density of single crystalline silicon. The influence of the sintering temperature on the thermoelectric properties is investigated. It was found that high sintering temperatures are beneficial for an enhancement of the power factor, while the thermal conductivity was only moderately affected. The optimization of the compaction procedure with respect to the transport properties leads to zT values of the p‐type nanosilicon of 0.32 at 700 °C, demonstrating the potential of our method.

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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.