I. A. Pronin

Relationship between the photocatalytic and photoluminescence properties of zinc oxide doped with copper and manganese

Comparison of the photocatalytic and photoluminescence properties of zinc oxide lightly doped with copper and manganese shows that the relationship between these two processes is due to several reasons, the most important of which are the crystalline state of the material and the type and concentration of the modifier. Raising the concentration of dopants makes the photoluminescence intensity higher and reduces the photocatalytic activity. It is shown that the mechanism by which a dopant is incorporated also affects the relationship under consideration and leads in some cases to deviation from the tendency mentioned above.

Sensitive elements of vacuum sensors based on porous nanostructured SiO2-SnO2 sol-gel films

The objects of investigation are porous nanostructured SiO2-SnO2 sol-gel films used as sensitive elements on vacuum sensors. The properties of the films with spherical, labyrinth, and percolation mesh structures are analyzed. It is shown that the resistance of sensitive elements based on these films sharply drops at a pressure below the atmospheric value. Processes taking place in the films at subatmospheric pressures are studied. It is found that the desorption of water vapor increases the resistance of the sensitive elements of vacuum sensors, whereas the desorption of carbon dioxide and oxygen decreases the resistance. This agrees with experimental data.

Correlations in infrared spectra of nanostructures based on mixed oxides

This paper has presented experimental data on the infrared spectroscopic investigation of nanostructures based on mixed oxides. Nanostructures in the form of porous thin films deposited on oxidized single- crystal silicon substrates have been synthesized by the sol–gel method. The qualitative composition of film-forming sols and the related nanostructures has been examined. Correlations relating the coefficient of transmission of infrared radiation through the materials under investigation and their quantitative composition have been established. The processes occurring during the annealing of the nanostructures in the temperature range from 100 to 600°C have been analyzed.

Nanolithographic self-assembly of colloidal nanoparticles

Methods of nanolithographic self-assembly of colloidal nanoparticles have been created, which are promising for the development of fractal nanolithography.

A new type of gas sensor based on the thermovoltaic effect in zinc oxide inhomogeneously doped with mixed-valence impurities

We propose a new type of potentiometric gas sensor operating on the basis of the thermovoltaic effect in uniformly heated (without temperature gradients) ZnO/ZnO–Fe sandwich structures obtained by the sol–gel method. It is established that a significant contribution to the gas responsivity of sensors is related to the thickness of the upper doped layer of the structure.

Study of the photodegradation of brilliant green on mechanically activated powders of zinc oxide

A study of the photocatalytic activity of commercial and mechanically activated zinc oxide powders has been carried out based on the example of the decomposition of Brilliant Green. The goal of this work was to study the effect of the grinding time (0, 1, 3, 5, and 7 min) on the structure of zinc oxide and its photocatalytic activity under visible and ultraviolet (UV) radiation. It has been found that, when UV radiation is used, the constant of the dye oxidation rate for samples activated for 1 min increases compared with unactivated powders, whereas further mechanical activation leads to a decrease in the photocatalytic activity. When using visible radiation, samples activated for 1 min showed the minimum photocatalytic activity and further mechanical activation led to an increase in the efficiency of photocatalysis.

Creating Lithographic Pictures Using Faceted Zinc Oxide Microparticles on a Silicon Substrate

Lithography techniques compatible with silicon technology have been developed within the hydrothermal method. Topological layouts were formed by faceted microcrystals with the developed surface. The prospects for implementing new hierarchical structures are of special interest.

Simulation of the sensor response of vacuummeters with sensitive elements based on multicomponent oxide nanomaterials with the fractal structure

We have proposed a mathematical model of the sensor response of vacuummeters with sensitive elements based on broadband semiconductor oxide with electrical conductivity of the n- and p-type, as well as the multicomponent oxide systems. The correctness of the model description of the dependence of the resistivity of nanomaterials synthesized by the sol–gel method and has the structure of spherical aggregates of fractal origin on the ambient pressure has been demonstrated. It has been shown that, taking into account the corrections, the developed model can be used to qualitatively describe the sensor response of nanomaterials based on two-component SiO2—SnO2 oxide systems with a labyrinth structure.

Synthesis and characterization of CuInSe2 core–shell quantum dots

A synthesis of 1-dodecanetiol stabilized colloidal quantum dots of CuInSe2 exhibiting photoluminescence in the range of 700–900 nm has been described. The effect of the shell on the energy levels of electrons in CuInSe2–ZnS and CuInSe2–ZnSe core–shell quantum dots has been investigated by quantum mechanical calculations.

The volt-ampere characteristics of resistive gas sensors in multisensor implementation: Distinctive features

This paper considers the major factors affecting the nonlinearity in the volt-ampere characteristics of resistive gas sensors. The authors establish that, under small gaps between sensor electrodes (particularly, in multisensor systems), the dominating contribution to the nonlinearity is made by three factors, namely, the drift of chemisorbed ions to an anode, the drift of protons on the surface to a cathode and the drift of intrinsic defects through the sublattice.