Prospects for Electrical Performance Tuning in CaCoO Materials by Metallic Fe and Ni Particles Additions.

This work further explores the possibilities for designing the high-temperature electrical performance of the thermoelectric CaCoO phase, by a composite approach involving separate metallic iron and nickel particles additions, and by employing two different sintering schemes, capable to promote the controlled interactions between the components, encouraged by our recent promising results obtained for similar cobalt additions. Iron and nickel were chosen because of their similarities with cobalt. The maximum power factor value of around 200 μWmK at 925 K was achieved for the composite with the nominal nickel content of 3% vol.

Redox-Promoted Tailoring of the High-Temperature Electrical Performance in CaCoO Thermoelectric Materials by Metallic Cobalt Addition.

This paper reports a novel composite-based processing route for improving the electrical performance of CaCoO thermoelectric (TE) ceramics. The approach involves the addition of metallic Co, acting as a pore filler on oxidation, and considers two simple sintering schemes. The (1-x)CaCoO/xCo composites (x = 0%, 3%, 6% and 9% vol.

Design of Multifunctional Titania-Based Photocatalysts by Controlled Redox Reactions.

This work aims at the preparation of multifunctional titania-based photocatalysts with inherent capabilities for thermal co-activation and stabilisation of anatase polymorph, by designing the phase composition and microstructure of rutile-silicon carbide mixture. The processing involved a conventional solid state route, including partial pre-reduction of rutile by SiC in inert Ar atmosphere, followed by post-oxidation in air. The impacts of processing conditions on the phase composition and photocatalytic activity were evaluated using Taguchi planning.

Exploring Tantalum as a Potential Dopant to Promote the Thermoelectric Performance of Zinc Oxide.

Zinc oxide (ZnO) has being recognised as a potentially interesting thermoelectric material, allowing flexible tuning of the electrical properties by donor doping. This work focuses on the assessment of tantalum doping effects on the relevant structural, microstructural, optical and thermoelectric properties of ZnO. Processing of the samples with a nominal composition ZnTaO by conventional solid-state route results in limited solubility of Ta in the wurtzite structure.