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Palladium nanoparticles were obtained by the photochemical reduction of the palladium(II) complex compounds K2[Pd(C2O4)2], [Pd(Gly)2], and [Pd(β-Ala)2] in a photolyte volume. The highest rate of formation of palladium nanoparticles in the photolyte volume is observed during the photolysis of the K2[Pd(C2O4)2] complex and the lowest—in the case of the [Pd(β-Ala)2] complex. Palladium particles obtained by the photolysis of aqueous solutions of the [Pd(β-Ala)2] and [Pd(Gly)2] complexes have the highest storage stability even in the absence of a stabilizer. When calcined in air in the presence of palladium nanocomposite particles on a CeO2 carrier, the temperature of the oxidation beginning decreases, and the weight loss of the sample (soot) increases.

Cu2O nanoparticles were synthesized by photoreduction of copper(II) complex compounds with ethylene glycol and glycerin in the photolite volume. Their optical properties, morphology, phase composition, and photocatalytic activity in methyl orange decomposition were studied. The electrochemical substitution reaction afforded Cu2O/Ag composite nanoparticles. Their increased activity in photodegradation reactions of methyl orange in comparison with unmodified Cu2O particles was found.

A number of anatase derivatives doped with iron, yttrium, and vanadium oxides were synthesized in a pressure reactor at 250°C by the solvothermal method in a solution of anhydrous capronic acid. It was shown that at certain iron and yttrium concentrations the photocatalytic activity of obtained samples exceeds the activity of the titanium dioxide nanopowder Aeroxide® P25 used as a standard.

Island copper-containing films consisting mainly of copper(I) oxide particles were obtained on a quartz surface by photochemical decomposition of copper(II) complex compounds with amino acids. The size and morphology of Cu2O particles and their dependence on the photolysis duration and the amino acid nature contained in the complex were established. The films obtained by the complex [Cu(β-Ala)2] photolysis have the highest photocatalytic activity in reactions of methyl orange photodecomposition.

Phase composition and structure of mesostructured materials, titanium dioxide and titanium dioxide modified with silver nanoparticles, have been studied by X-ray diffraction analysis. Introduction of Ag(I) ions into the initial composition and variation of the annealing temperature over the 500–950°C range allows controlling the anatase to rutile crystal phase ratio in the samples. The photocatalytic activity of TiO2 and TiO2/Ag samples has been demonstrated using the methyl orange degradation reaction. The catalytic properties of the materials have been found to depend on the anatase to rutile phase ratio and on the presence of silver nanoparticles.

Recently considerable attention is given to the preparation of nanosize semiconductor particles (TiO2, CeO2, Cu2O, etc.), as in the nanodispersed state they have special optical, photocatalytic, magnetic, and antibacterial properties, which are not typical for bulk materials. Copper(I) oxide is a p-type semiconductor with a forbidden gap of 2.0–2.2 eV, therefore it shows photocatalytic properties under the influence of visible light and can serve as the basis for manufacturing materials converting solar energy to electric energy [1–4]. Nanosize Cu2O particles possess antibacterial activity with respect to both gram-positive and gramnegative microbial strains [5, 6].

A procedure was developed for the synthesis of gold and silver nanoparticles in the presence of polyols like ethylene glycol, diethylene glycol, triethylene glycol, and 1,2-propylene glycol. Spectral characteristics of the obtained nanocomposites were mesured and kinetics of the formation of the colloidal phase was studied. The influence of the polyol nature and concentration on the photoinitiated formation of silver and gold nanoparticles was studied. The 1,2-propylene glycol is shown to exhibit maximal stabilizing effect.

Results of studying kinetics of formation of hollow bimetal nanoparticles (nanocages) based on silver and gold that are obtained by the three-stage synthesis are presented. The factors defining sizes, structure, composition, and optical properties of nanocages were revealed by means of high-resolution transmission electron microscopy and energy-dispersive X-ray spectroscopy.

A pioneering procedure is presented for the photochemical synthesis of aqueous solutions of hollow bimetal silver-gold nanoparticles in the presence of poly-N-vinylpyrrolidone. The structure and properties of synthesized nanocages were studied by the methods of high-resolution transmission electron microscopy, UV visible spectroscopy, and energy-dispersive X-ray structural analysis. The mechanism of the formation of AgAu nanocages was suggested on the basis of the experimental data.

The results were reported for the survey undertaken in Moscow and Krasnodar krai with the aim to elucidate the users’ attitudes toward collection of spent household batteries. Their utilization is one of the most important problems of municipal solid waste management, whose solution involves organization of spent battery collection as the task of the worst complication. Based on the specially designed questionnaire, the users’ willingness to participate in collection of spent batteries, as well as the preferred conditions for discarding spent and purchasing new batteries were determined.

An effective procedure for the synthesis of bimetal nanoparticles Ag nucleus-Cu shell was developed. The use of a composition based on Na2[CuEDTA] and AgNO3 with N-polyvinylpyrrolidone as a stabilizer of nanoparticles is optimal for the synthesis of bimetal particles. Spectral characteristics of the bimetal nanoparticles were investigated, and the kinetics of the metal phase formation in aqueous solutions was studied.

Results of photochemical precipitation of copper nanoparticles on the surface of polybutoxytitanium film applied to the surface of quartz sublayer and modified by the UV irradiation with the excitation wavelength 254 nm are presented. Photocatalytic activity of polybutoxytitanium film modified by the UV light was confirmed. It was established that photoprecipitated copper nanoparticles form a uniform stable coating consisting of tightly packed particles of 50 nm diameter and 8 nm height.

Photochemical deposition of copper nanoparticles onto polystyrene surface under monochromatic (λ 254 nm) and unfiltered irradiation was studied. The kinetic parameters of this process depending on the concentration of copper(II) coordination compound and the size of polystyrene microspheres were determined. A procedure was tested for the preparation of monodisperse copper nanoparticles from colloidal copper chemically synthesized in ethylene glycol matrix in the presence of polystyrene with a microsphere size of 100 nm.

The results of studying optical properties of silver films deposited photochemically on a quartz surface are presented. The films consist of isolated silver particles of 5–50 nm in size and of agglomerates of several micrometers in size and contain up to 7 wt % of Ag2O. Treatment of the films with dimethylformamide solution of [Pden2](BPh4)2 results in a decrease in the average particle size due to dissolution of small particles (5–15 nm) and destruction of greater agglomerates.

The results of silver photochemical deposition on a surface of titanium-containing coatings are presented. The formation of the particles occurs in a near-surface layer with a direct involvement of the coating which gains an anatase structure under the action of UV light. The deposition of silver begins with the formation of low-atomic clusters which reach particle sizes of 300 nm in diameter and 35–40 nm in thickness under long irradiation. The quantum yield of the reduction of Ag(I) ions is 0.001.

Gold particles are formed by photochemical reduction of HAuCl4 in the bulk of poly(butyl acrylate) elastomer films under the action of monochromatic light with the wavelengths of 254 and 365 nm with direct participation of the ester chromophore group of the polymer having intrinsic photosensitivity in the near-UV range (254 nm). On irradiation at the wavelength of 365 nm, the reduction of HAuCl4 is ineffective and stops at the stage of Au(I) formation. The physicomechanical properties of elastomer films modified with gold particles (tensile strength and relative elongation) were studied.

Photochemical synthesis of gold nanoparticles in aqueous dispersions of carboxylated polystyrene with microsphere sizes of 100, 300, 500, and 1410 nm under the action of monochromatic light with an excitation wavelength of 254 nm was studied. Preliminary irradiation of the polymer dispersion induces formation of gold particles under dark conditions. Dependences of gold nanoparticles formation on the duration of preliminary polymer irradiation and concentration of introduced HAuCl4 aqueous solution were determined. A mechanism of the polystyrene-assisted formation of gold nanoparticles was proposed. The size and structure of gold nanoparticles were determined.

Photochemical deposition of silver nanoparticles in poly(butyl acrylate) and poly(butadiene-styrene) under the action of monochromatic UV light (254 nm) was studied. Changes in the polymer structure in the course of photolysis were revealed and analyzed. A mechanism of formation of silver nanoparticles was suggested. Electron microscopic examination showed that the efficiency of the particle formation is determined by the residual moisture content of the polymer films. Physicomechanical properties (tensile strength and relative elongation) of the elastomer films containing silver nanoparticles were studied.

Silver nanoparticles were deposited photochemically under the action of monochromatic (254 nm) and unfiltered light on the surface of 100- to 1410-nm polystyrene globules. The kinetic relationships of the photodeposition, as influenced by the concentration of silver ions in the photolyte and the size of polystyrene globules, were determined. An electron microscopic examination showed that the photoreduction mainly occurs on the surface of the polymer globules, and the size of the forming nanoparticles does not exceed 60 nm. The silver nanoparticles are characterized by a narrow size distribution.

Original methods of photochemical preparation of stable mono- (Cu, Ag, Au, Ni, Pd, Pt) and bimetallic nanoparticles in the form of optically transparent compact films on quartz surface and of volume dispersions in porous inorganic (silica glasses) and organic (MF-4SK fluorocarbon) materials, solid polymers (polyvinyl alcohol, polyethylene glycol, gelatin, latexes), and in liquid media (glycerol) are reviewed. The results of studies of spectral and structural characteristics of nanophase films under various experimental conditions are presented. Experimental mechanistic models and ways of controlling disperse composition of metal colloids, which can be used for photochemical synthesis of nanophase systems, are proposed.