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This article described the photocatalysts for wastewater treatment based on copper oxide (II). Research results of CuO nanowhiskers photocatalytic properties are showedand a series of nanowhiskers tests on organic pollutant (methylene blue)are given. It is shown that the copper oxide nanowhiskers able to purify water from organic pollution.

This article presents the results of experimental obtaining together with tests of modifications of the granulated sorption aluminosilicate-based material. The chemical composition, structure and morphology of a surface of the obtained modifications of sorbents from clay have been explored. Through a complex of modern physical methods it is established that porosity and a specific surface of clay-based sorbents increased as a result of modification. Pilot studies have shown higher efficiency of new aluminosilicate-based sorbents in comparison with absorbent carbon during sorption of such model pollutants as methylene blue, phenol and ions of heavy metals. Modifications of sorbent which can be effectively used for post treatment of wastewater are revealed.

The influence of temperature fields and different reactive media on the structure and morphology of small icosahedral particles (ISPs) are investigated. It is shown experimentally that ISPs of micron size can be transformed into advanced functional materials with a developed surface. The leading role of disclination defects for the transformations occurring in ISPs is established. Potential fields of application of the new functional materials based on transformed ISPs are discussed.

We present experimental facts on the role of electrolyte pH in shape control of electrodeposited small silver microcrystals. Increasing electrolyte pH value, i.e. the transition from acidic to alkali solutions, causes the change of microcrystal habitus from strongly distorted (pH ß 4) through faceted (pH ß 7) to smooth hemispheric (pH ß 10) ones. At neutral pH ß 7 the observed silver microcrystals demonstrated shapes with pentagonal symmetry including icosahedral microcrystals with incoming pentagonal facets at the icosahedron vertices that is unique for single-component small metallic particles. Such faceting has previously been reported only for bicompounent B 6 O icosahedral small particles [H. Hubert et al., Nature 391, 376 (1998)].It is well known, that the size of a physical object is an important parameter substantially determining its properties [1]. At the range of nano-and microscale small particles and microcrystals often demonstrate nontrivial features. In particular, decahedral or icosahedral morphology is documented for small particles for materials with FCC crystal structure [2-6]. Such particles are referred to as pentagonal small particles (PSPs). Decahedral small particles (DSPs) and icosahedral small particles (ISPs) can be composed of, respectively, five and twenty weakly distorted tetrahedral single-crystal regions. An individual tetrahedron possesses FCC closepacked crystal structure. Neighbor tetrahedra are joined on {111}-type crystallographic planes, which become twin boundaries inside PSPs. It is due to this fact such objects are also designated as multiple-twinned particles [2][3][4][5][6].Small metal particles including multiple-twinned ones can be fabricated by various techniques, in particular, by nucleation from a gas phase with the use of physical or chemical vapor deposition onto a substrate [1]. Electrodeposition from an electrolyte solution plays an important role among the methods of fabrication of metal microparticles. This simple technique demonstrates a big variety of the control parameters such as electrolyte chemical composition, electric current density, cathode overvoltage, deposition time, process temperature, and the type of substrate. For example, variation in the chemical composition of the electrolyte, but for the same deposited metal, leads to considerable changes in the structure of the fabricated objects [7].In the present work, we investigate the effect of electrolyte pH on the morphology of the electrodeposited small silver particles and microcrystals and describe atypical shapes of silver PSPs.To fabricate silver small particles and microcrystals, we used a solution prepared with a distilled water and containing 35 g/l of silver nitrate AgNO 3 and 150 g/l of ammonium sulfate (NH 4 ) 2 SO 4 . The control parameter was electrolyte рН varied from 4.0 to 10.0 by adding a 25-percent aqueous solution of ammonia NH 4 OH. For reproducibility of experimental results, deposition of silver was carried out in a potentiostatic regime with cathode overvoltage of 100 . . . 1...