Field-assisted sintering technology/Spark plasma sintering is a low voltage, direct current (DC) pulsed current activated, pressure-assisted sintering, and synthesis technique, which has been widely applied for materials processing in the recent years. After a description of its working principles and historical background, mechanical, thermal, electrical effects in FAST/SPS are presented along with the role of atmosphere. A selection of successful materials development including refractory materials, nanocrystalline functional ceramics, graded, and non-equilibrium materials is then discussed. Finally, technological aspects (advanced tool concepts, temperature measurement, finite element simulations) are covered.

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Crystallite size effects can influence the performance of battery materials by making the structural chemistry deviate from what is predicted by the equilibrium phase diagram. The implications of this are profound: the properties of many battery materials should be reassessed. Sodium ion battery anodes made from nanocrystalline bismuth form different phases during electrochemical cycling compared to anodes with larger crystallites. This is due to the formation of a metastable cubic polymorph of Na 3 Bi on the crystallite surfaces. The structural differences (weaker Na−Bi bonds, different coordination of Na to Bi) between the metastable cubic Na 3 Bi phase found in the nanocrystals and the hexagonal equilibrium polymorph which dominates the larger crystallites offer an explanation for the improvements in cycling behavior observed for the nanostructured anode.

A new synthesis scheme for the formation of porous CeO2/Pt-polycarbosilane composites using inverse microemulsions is presented. Aqueous hexachloroplatinic acid was used as a hydrosilylation catalyst causing crosslinking of allyl groups in a liquid polycarbosilane (PCS). The resulting polymers are temperature stable and highly porous. The Pt catalyst content and post-treatment of the polymer can be used to adjust the porosity. For the first time hydrophobic polymers with specific surface areas up to 896 m(2)/g were obtained by catalytic crosslinking of polycarbosilanes. Ceria nanoparticles 2-3 nm in diameter are well dispersed in the PCS matrix as proven using high resolution electron microscopy. Porosity of the hydrophobic materials could be increased up to 992 m(2)/g by adding divinylbenzene in the oil phase. Pyrolyses at 1200-1500 degrees C and post-oxidative treatment at various temperatures produce porous ceramic structures with surface areas up to 423 m(2)/g. X-Ray diffration investigations show that the crystallinity of the SiC matrix can be controlled by the pyrolysis temperature. Post-oxidative treatments cause silicon oxycarbide formation. Structure and morphology of the polymeric and ceramic composites were investigated using Si-29 MAS NMR, FESEM, FT-IR and EDX techniques. The temperature programmed oxidation (TPO) of methane shows a high catalytic activity of CeO2/Pt-SiC(O) composites lowering the onset in the TPO to 400-500 degrees C

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