High-temperature superconductors precursors

The intensive development of the chemistry of homo- and heterometallic alkoxides of copper started more than 10 years ago in connection with the prospects of their application in the preparation of materials and initially in high temperature superconductors. In the search for the appropriate precursors in sol-gel and MOCVD techniques, attention was focused on the alkoxides of copper (I) and the fluorinated alkoxides of copper (II) — oligomeric derivatives soluble in non-polar solvents and existing not only in condensed but also in the gas phase. The derivatives of copper (II) and aliphatic alcohols, even rather branched or functional ones (such as alkoxyalkoxides) turned out to be polymeric substances uninteresting for further application. 

Interest in the development of metal-organic precursors for the lanthanide elements is due to the many important apphcations of lanthanide-containing materials. These include erbium-doped semiconductors for use as optical fiber communications, lanthanide-doped GaN for fiiU color displays, high-temperature superconductors, and lanthanide-doped ferroelectric see Ferroelectricity) phases. Despite the importance of these materials, lanthanide film growth precursors... 

Narlikar, A. (2001). Essential Chemistry of High-Tc Cuprate Synthesis through the Solution Precursor Methods, In Studies of High Temperature Superconductors, Nova Science Publishers, New York, ISBN 1-59033-026-9... 

When the desired phase is not stable under conditions of solution synthesis such as those of high-temperature superconductors, even application of singlesource precursors does not help to facilitate their formation [141]. 

The nanorod represents an important building block for nanostructures. Nanorods would be useful as reinforcements in metal and ceramic matrix composites as well as ideal structures with which to pin vortices in high-temperature superconductors (119). Whiskers represent attractive reinforcing additives for metal and ceramic matrix compositions to impart more strength to the ceramic object. The superior performance of titanium carbide reinforcements is found in two different forms, discontinuous fiber and hollow microspheres, by controlled morphology carbide synthesis where titanium and carbon precursors combine in specially designed graphite... 

Bismuth is an important element in many of the new high-temperature, oxide superconductors and in a variety of heterogeneous mixed oxide catalysts. Some of the methods employed in the preparation of these materials, namely sol-gel and chemical vapor deposition processes, require bismuth alkoxides as precursors and a number of papers on these compounds have recently been published.1 One synthetic route to bismuth alkoxides, which avoids the more commonly used trihalide starting materials and the often troublesome separation of alkali metal halides, involves the reaction between a bismuth amide and an alcohol according to the following equation ... 

---