Phase stability, nanostructured materials

Recent scientific literature demonstrates a growing interest in new methods of nanoparticle synthesis, driven primarily by an ever-increasing awareness of the unique properties and technological importance of nanostructured materials. The fabrication of nanoparticles within reverse microemulsions [40, 146] has been shown to be a convenient route to monodisperse particles of controllable size. A recognised goal of these synthetic approaches is to achieve control over the composition, size, surface species, solubility, stability, isolability and other functional properties of the nanostructures. The combination of reverse microemulsion and microwave heating has the added advantage that the oil phase in the reverse microemulsion system is transparent to microwave so that the aqueous domains are heated directly, selectively and rapidly. 

Rose, M., Gorzawski, G., Miehe, G. et al. 1995. Phase stability of nanostructured materials under heavy ion irradiation. Nanostruct. Mater. 6 731-734. 

Abstract Screened electrostatic interactions are commonly employed in colloid and polymer science for stabilization in aqueous solutions to avoid macroscopic phase separation, but these are equally versatile as driving force for complexation (or microscopic phase separation) into micelles, vesicles, multilayers and other nanostructured materials. In this introductory chapter, we present an overview of the field of electrostatically driven assembly of polyelectrolytes into nanometresized association colloids focusing in particular on the fundamentals followed by a discussion of selected application areas. 

Effect of Nanostructured Materials Nature on Phase Stability.228... 

EFFECT OF NANOSTRUCTURED MATERIALS NATURE ON PHASE STABILITY... 

Related systems It should be noted that specific properties for applications could be enhanced by using solid solutions, doped materials, and composites, instead of pure ceria. For example, ceria-zirconia solid solution is a well known ceria based material for enhanced OSC and high ionic conductivity for solid state fuel cell components. It is also used in the three way catalysts for automobile waste gas cleaning, because of the improved thermal stability, surface area, and reducibility. The synthesis, structure, and properties of ceria-zirconia have been actively studied for a long time. Di Monte and Kaspar et al. presented feature articles on the nanostructured ceria—zirconia-mixed oxides. The studies on phase, structures, as well as the microstructures are discussed and reviewed (Di Monte et al., 2004). 

Thin films of nanostructured metals and semiconductors (e.g., Pt, Sn, CdTe) can be prepared by electrodeposition of the metal ions doped into the Hi LLC phase [40,47,48]. Similar to the precipitation of CdS, these films can retain the symmetry of the LLC template during the deposition. These materials allow one to combine well-defined porous nanostructures, high specific surface areas, electrical connectivity, fast electrolyte diffusion, and good mechanical and electrochemical stability. With this approach, hexago-nally structured semiconductor films of uniform thickness can be prepared. Nanostructured thin films of this type are proposed to have relevance in catalysis, batteries, fuel cells, capacitors, and sensors. 

Polymeric materials have advantages because of their stability and structureforming properties. Electron- and ion-active organic polymeric materials have attracted attention for new devices. In Chapter 5, Kato and co-workers focus on polymeric liquid crystalline materials that are used for the development of functional materials transporting ions and electrons. The nanostructures such as smectic and columnar phases exhibited by side-chain, main-chain, dendritic, and network polymers may exhibit one- and two-dimensional transportation properties. 

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