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Nowadays, modern technical solutions in various spheres of human activity from the opto-electronics up to nanobiotechnology are increasingly dependent on the level of technology. Applied research on nanomaterials plays a key role in the development of nanotechnologies. The nanostructured silicon is one of the materials attracting the special attention of researchers in various applied areas. A new and widely discussed application of nanostructured silicon is a possibility of their usage in the process of efficient hydrogen generation. The present paper is devoted to a brief review of recent advances in the study of the applicability of porous silicon nanostructures for hydrogen generation. The main possible mechanisms of the photocatalytic activity of silicon nanostructures, as well as the influence of such parameters as their shape, size and degree of surface development on the hydrogen generation efficiency of the material are discussed. In addition, based on literature overview, an analysis regarding the most likely paths for the development of this area of semiconductor materials science and an assessment of the feasibility of using silicon nanostructures for hydrogen generation has been made. [ABSTRACT FROM AUTHOR]

Photovoltaics (PV) is a key technology option for realizing a decarbonized power sector and sustainable energy supply and can be deployed in a modular way almost everywhere on this planet. Solar resources across the world are abundant and cannot be monopolised by one country. Regardless of how fast energy prices grow in the future, and the reasons behind these grow, PV and other renewable energies are the only ones offering the stabilization of, or even a reduction in future prices. Kazakhstan has significant renewable potential solar power. In spite of this, the country is currently dependent upon fossil fuels for power generation. Coal fired plants account for 75% of total power generation leading to concerns over greenhouse gas emissions and impacts on human health and the environment. This article reviews the current worldwide PV market situation and recent projects in Kazakhstan. As the government of country plans to bring the share of renewable energy in electricity generation to 3% by 2020 rising to 30% by 2030 and 50% by 2050 this implies that Kazakhstan will need to invest more on the development of renewable energy. [ABSTRACT FROM AUTHOR]

Gallium phosphide is a semiconductor material of great interest for new LED technologies. Porous AIIIBV are of great interest because of their interesting optical properties different of those for bulk material. The main goal of this research work is to obtain nanostructured porous gallium phosphide (por-GaP) layers by electrochemical etching of the monocrystalline (100) p-type GaP substrate surface. The structure and surface morphology of obtained samples were studied by scanning electron microscopy (SEM), atomic force microscopy (AFM) and Raman spectroscopy. The chemical composition of nanostructured GaP surfaces was studied by Energy Dispersive X-Ray (EDX) spectroscopy. It was found that shape and size of structures is strongly depending on electrochemical etching conditions. At constant applied voltage and varied current we observe that the pore size is increasing from 10 microns to 50 microns, and at fixed current, but varying the voltage the pore diameters can be achieved in the range between 100 to 200 nanometers. [ABSTRACT FROM AUTHOR]

Total (specular+diffusive) reflection of nanostructured Si layers prepared by metal assisted chemical etching (MACE) of crystalline silicon (c-Si) wafers is investigated. The thickness of nanostructured Si layers is varied from 0.3 to 100 µm by increasing the MACE time. The time dependence of silicon nanostructured layers thickness on the etching time was found to be logarithmic. Spectra of the total reflection were measured in optical range from 0.2 to 2 µm. Depending on the thickness of sample, it was observed a low level of the total reflection near 1% in the ultraviolet (UV)-visible spectral ranges and a strong increase up to 80% in the infrared (IR) optical range above 1 µm. The low reflection in UV-visible region is explained by partial localization of light in Si nanostructures accompanied with the strong light absorption. The enhanced IR reflection is probably related to the strong scattering of light by silicon nanocrystals in the transparency region. The maximal total reflection in the IR range was found for the layer thickness of about 30 µm. An effect of doping of Si nanostructures by donor and acceptor impurities on the total reflection in the IR region was observed. The obtained results can be useful to prepare new materials with desired properties for photonic applications. [ABSTRACT FROM AUTHOR]

Engineering novel material structures has continually been pursued to further advance modern technologies. These advancements often rely on novel processing technologies. Although many processing parameters have been thoroughly examined in the field of composition coatings, the formation processes are an exception. In this work, we examine the unique microstructures of composite electrolytic coatings, obtaining from electrolytes-suspension which contains nano-size particles of SiO2 and carbon. Metallographic researches were carried out for an establishing the reasons of essentially differences in corrosion resistance of nano- nano-composition electrolytic coatings received at various electroplating temperatures. The results of corrosion investigation show, that the best corrosion resistance has nano-composition electrolytic coatings received at 333 K temperature. This novel electro-deposition technology has the potential to open new areas of research such as obtaining materials with desired functional properties. [ABSTRACT FROM AUTHOR]