SrTiO 4, preparation

Nano BaTiOs, like nano-SrTiOs prepared by coprecipitation, can effectively remove Cu from solutions by adsorption and can be used for environmental remediation applications [61]. 

Xuewen W, Zhiyong Z, Shuixian Z (2001) Preparation of nano-crystalline SrTiOs powder in sol-gel process. Mater Sci Engg B 86 29-33... 

Ohno T, Akiyoshi M, Umebayashi T, Asai K, Mitsui T, Matsumura M (2002) Preparation of S-doped Ti02 photocatalysts and their photocatalytic activites under visible light. Appl Catal A Gen 265 115-121 Miyauchi M, Takashio M, Tobimatsu H (2004) Photocatalytic activity of SrTiOs codoped with nitrogen and lanthanum under visible light illumination. Langmuir 20 232-236... 

The best superconducting films are obtained on substrates such as SrTiOs, MgO or ZrOz. Some authors have succeeded in the preparation of films on Si, but using a MgO buffer that was first sputtered onto the substrate (38). 

There have been some reports of superconducting thin films of Nd2 xCexCu04 prepared by laser ablation (38)(39). The films are prepared from sintered Nd1 5Ce015Cu04 targets on heated (100)-SrTiOs substrates. Typical conditions are 500°C at an ambient oxygen pressure of 10"4 atm, followed by annealing at 900°C. 

Fig. 4.16. (a) An optical image of the diamond distribution on the thin-film surface (b) a low-magnification image of a YBCO thin film grown on a SrTiOs substrate, prepared by this method (c) an HREM image from one of these thin areas and (d) a H M image where one can clearly see the atomic structure. 

These bicrystals are the substrates that have been typically used for the preparation of individual grain boundaries in YBCO thin films [11.1-11.3]. The reason that SrTiOs is chosen as the substrate for YBCO is primarily due to the closeness of the lattice parameters (3.905 A for SrTiOs compared with a = 3.81 A and b = 3.88 A in YBCO). In view of the fact that YBCO, and for that matter all of the high superconductors, have structures that are essentially perovskite, it is reasonable to assume that the structure of the YBCO grain boundary would follow that of the SrTiOs bicrystal. Indeed, in terms of the dislocation core models, the only difference between SrTiOs and YBCO are that the Sr columns are replaced by Y/Ba columns and the Ti—O columns are replaced by Cu—O columns. The structure in the [001] projection is the... 

Herrig and Hempelmann have prepared BaTiOa, BaZrOs, SrTiOs and SrZrOs perovskites by hydrolysis of the corresponding metal alkoxides in a microemulsion system . A strong relationship between the hydrolysis rate and water content of the microemulsion was reported. 

S. M. Zanetti, E. R. Leite, E. Longo, and J. A. Varela. Cracks developed during SrTiOs thin-film preparation from polymeric precursors. Appl. Organomet. Chem., 13 373-382, 1999 V. Bouquet, M. 1. B. Bernard , S. M. Zanetti, E. R. Leite, E. Longo, J. A. Varela, M. G. Viry, and A. Perrin. Epitaxially grown LiNb03 thin films by polymeric precursor method. J. Mater. Res., 15 2446-2453, 2000... 

E M, Pontes, E, R, Leite, E, J, H, Lee, E, Longo, and J, A, Varela, Dielectric properties and micro structure of SrTiOs/BaTiOs multilayer thin films prepared by a chemical route. Thin Solid Films, 385 260-265, 2001... 

This paper tries to link different properties of a Sr(Ti,Fe)03 perovkite with PtRu metal catalyst for high and low temperature applications. The ceramic/metal (SrTio.85Feo.i503.d)o.5(PtRu)o.5 cermet is prepared by combustion synthesis, as well as the material achieved are studied and characterised as electrocatalyst. 

FIGURE 20.7 Flow chart for preparing SrTiOs powders by the Pechini method. 

Fig. 14 Electron microscopy images of heterodimer hybrid nanoparticles prepared using a pulsed later ablation in liquid method (a-d, h, i) Au-CoFe204 and (e-g) Au-SrTiOs. The scale bar is 5 nm. Reproduced with permission from ref. 51. Copyright 2013 Wiley-VCH. ...

A recent and even more exceptional example of enhanced ionic conductivity due to the introduction of heterointerfaces was reported by Garcia-Barriocanal et al., who prepared YSZ/SrTiOs multilayers by using MBE, and recorded a conductivity increase by up to eight orders of magnitude that was ascribed to increases in the oxygen ion conductivity of the YSZ layers [56], Confirmation of these results await either electron-blocking experiments [23] or open-circuit Nernst potential studies [57]. 

The Pechini method refers to an original process developed by Pechini (95) for the preparation of titanates and niobates for the capacitor industry. The method has since been applied to many complex oxide compositions (96,97). Metal ions from starting materials such as carbonates, nitrates, and alkoxides are complexed in an aqueous solution with a-carboxylic acids such as citric acid. When heated with a polyhydroxy alcohol, such as ethylene glycol, polyesterification occurs, and on removal of the excess liquid, a transparent resin is formed. The resin is then heated to decompose the organic constituents, ground, and calcined to produce the powder. The typical steps in the method are illustrated in Figure 2.34 for the preparation of SrTiOs powders (98). 

Microemulsions have been used to prepare SrTiOs, SrZrOs, Ce02, and Sn02 as well as magnetic particles and YBaCuO superconductors. 

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