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Modern progress in photopharmocology calls for new generation of compounds joining bioactivity, photoswitchable properties and high selectivity of response to light wavelength. Introduced here, phosphonate-fullerene hybrids are the first representatives of such compounds. Phosphonate-fullerene hybrids were synthesized on a base of fullerene C

The specific luminescence behavior of crystalline oxide particles doped with rare earth ions strongly depends on the initial composition of the host material and synthesis conditions. This issue is especially significant for non-isovalent doping in the crystal lattice. In this case, the formation of the structure is accompanied by the formation of point defects serving as charge compensators. The work is devoted to the synthesis of CaWO4:Nd3+ particles in the salt melt (modified Pechini method) and the study of structural and luminescent properties under varying synthesis conditions. It was found that temperature and duration of heat treatment in the salt melt (KCl) affected the crystal structure, the size of coherent scattering regions, luminescence intensity, and lifetime. An increase of heat treatment temperature led to a reduction of luminescence intensity and lifetime due to the formation of point defects. The optimal synthesis conditions for obtaining the highest luminescence intensity of CaWO4:Nd3+ crystalline particles in salt melt were found to be the following Т1= 600 °C; t1=2 h (the stage of polymer gel thermal treatment), Т2= 800 °C; t2=1 h (the stage of thermal treatment in KCl salt melt). As-synthesized CaWO4:Nd3+ powders contain both coarse and fine fractions. However weak particle agglomeration allowed obtaining a water dispersion with individual nanoparticles (up to 200 nm) after ultrasonic treatment. According to the obtained results, the synthesized material is characterized by high luminescence intensity and high dispersion, and promising as fluorescent thermometers and biological labels.

The effect of laser activation on butyrylcholinesterase inhibition by a series of phosphorylated arylaminomalonates with different substituents in the phenyl ring is demonstrated.

An in situ microsynthesis of polyaniline films directly on a substrate was developed and considered from the viewpoint of conductivity as a key functional property. The microsynthesis was carried out in a reaction volume of 60 μL. The multi-analytical study of polyaniline samples obtained by in situ microsynthesis was performed. The effect of synthesis parameters (reaction time, temperature, and number of synthetic procedures on the same substrate) on the structure, morphology and conductivity was investigated. It was shown that the in situ microsynthesis allows for the formation of polyaniline films in the whole range of synthesis parameters chosen. The correlations between synthetic conditions, structural parameters and conductivity are discussed. The found correlations between FTIR parameters and conductivity can be considered as a promising tool for PANI characterization.

We developed a rapid and effective technique for fabrication of sensor-active copper-based materials on the surface of such flexible polymers as terephthalate, polyethylene naphthalate and polyimide using the method of laser surface modification. For this purpose, we optimized the polymer surface activation parameters using laser sources with a picosecond pulse duration for subsequent selective metallization within the activated region. Further, the fabricated copper structures were modified with gold nanostructures and by electrochemical passivation to produce copper-gold and oxide-containing copper species, respectively. As a result, in comparison with pure copper electrodes, these composite materials exhibit much better electrocatalytic performance concerning the non-enzymatic identification of biologically important disease markers as glucose, hydrogen peroxide and dopamine.

The development of new contactless thermal nanosensors based on a ratiometric approach is of significant interest. To overcome the intrinsic limitations of thermally coupled levels, a dual activation strategy was applied. Dual activation was performed using co-doped single nanoparticles and a binary mixture of single-doped nanoparticles. Co-doped and mixed YVO4:Nd3+/Eu3+ nanoparticles were successfully demonstrated as luminescent nanothermometers and their thermometric performance, in terms of thermal sensitivity, temperature resolution and repeatability, was studied and compared.

A novel single-step, laser-induced and solution-based process is presented for synthesizing complex hybrid metal/carbon nanostructures. The process relies on simply illuminating the interface between a substrate and a liquid solution of the supramolecular complex [Au13Ag12(C2Ph)20(PPh2(C6H4)3PPh2)3][PF6]5 (hereinafter abbreviated as SMC) with an unfocussed He–Cd laser having a wavelength of 325 nm and an intensity of I = 0.5 W/cm2. The process results in hybrid nanostructures of well-controlled morphology: nanoparticles (NP) and 2D flakes, which may also grow jointly to form 3D morphologically complex multipetal ‘flower-like’ structures. At the atomic scale, the obtained metamaterials are complex in composition and structure, i.e., they contain bimetallic Au–Ag nanoclusters of diameter 3–5 nm incorporated inside a carbonaceous matrix. This matrix can be amorphous or crystalline, and the details of the compositional outcome can be controlled and steered by the laser deposition parameters. Au–Ag nanoclusters show plasmonic behavior including the enhancement of electromagnetic fields of visible light. This leads to the enhancement of Raman scattering by the Au–Ag nanoparticle ensemble within the carbonaceous matrix. This enables a 3D architecture for stimulating surface-enhanced Raman scattering (SERS).

The preparation of a highly ordered nanostructured transparent electrode based on a combination of nanosphere lithography and anodization is presented. The size of perfectly ordered pore domains is improved by an order of magnitude with respect to the state of the art. The concomitantly reduced density of defect pores increases the fraction of pores that are in good electrical contact with the underlying transparent conductive substrate. This improvement in structural quality translates directly and linearly into an improved performance of energy conversion devices built from such electrodes in a linear manner.

The laser induced curing of acryloxy terminated ethyleneoxide dimethylsiloxane-ethyleneoxide ABA block copolymer (PDMS-AO) and (3-glycidoxypropyl)trimethoxysilane (GPTMS) was carried out with 2-hydroxy-2-methylpropiophenone as radical photoinitiator and p-(octyloxyphenyl)phenyliodonium hexafluoroantimonate as cationic photoinitiator, respectively. The cross-linking mechanisms for both mixtures were determined through monitoring of photocuring by SSNMR, FTIR and Raman spectroscopies. The obtained silicone rubbers were tested by swelling measurements and thermogravimetric analysis. In comparison with PDMS-AO, cross-linked GPTMS had slightly more cross-linking density (by approximately 20% more). The cross-linked GPTMS was more thermally stable in air than cured PDMS-AO (by c.a. 190° C) due to both mechanisms: epoxy polymerization and Si–O–Si formation. The possibility of laser printing with defined framework for PDMS-AO was successfully demonstrated that allows obtaining laser printed polymer objects.

In this chapter, the contactless thermal sensors based on luminescence properties of rare earth-doped nanocrystalline phosphors are discussed. The luminescence thermometry is considered nowadays as a remote and noninvasive approach providing excellent functional parameters—high thermal sensitivity and spatial resolution, wide working temperature range and short response times. The competitive advantage of the luminescence thermometry is its applicability in specific environmental conditions like external electromagnetic field, fast-moving objects, flows and fluids of different nature. The key functional characteristics of temperature sensors are described in the chapter together with different strategies of temperature readout including variants of ratiometric approach via thermally coupled levels, Stark sublevels, spectral line position, and bandwidth and lifetime thermometry. Further progress in this direction includes stimulated market demands and industrial development of micro- and nanoelectronics, photonics, nanomedicine, micro- and nanofluidics, as well as academic interest and scientific challenge in the improvement of current intrinsic limitations. The presented analysis of emerging new directions in the field of luminescence thermometry testifies an interest in widening the working spectral range, development of multi-sensing devices based on multiple emission centers, etc. All these open fascinating prospects of luminescence thermometry in the future and development of even newer fields such as multimodal imaging with temperature monitoring, 3D temperature mapping, and temperature-supervised processes.

Herein, the synthesis, design, and the physicochemical characterization of phosphorus functionalized thiazolotriazole (PFT) compound are presented. The PFT tests on the biological activity revealed butyrylcholinesterase inhibition that was confirmed and explained with molecular docking studies. The pronounced reduction of optical density and biological activity was found as a result of irradiation of the PFT water solution with laser beam at wavelength 266 nm. The observed phenomenon was explained on the base of molecular dynamics, docking, and density functional theory modeling by the formation of PFT conformers via laser-induced phosphonate group twisting. The reorganization of the PFT geometry was found to be a reason of butyrylcholinesterase inhibition mechanism change and the site-specificity loss. These results demonstrate that PFT combines photoswitching and bioactive properties in one molecule that makes it promising as a molecular basis for the further design of bioactive substances with photosensitive properties based on the mechanism of the phosphonate group phototwisting.

For the oxidation of water to dioxygen, oxide-covered ruthenium metal is known as the most efficient catalyst, however, with limited stability. Herein, we present a strategy for incorporating a Ru/C composite onto a novel nanoporous electrode surface with low noble metal loading and improved stability. The Ru/C is coated on the pore walls of anodic alumina templates in a one-step laser-induced deposition method from Ru3(CO)12 solutions. Scanning electron microscopy proves the presence of a continuous Ru/C layer along the inner pore walls. The amorphous material consists of metallic Ru incorporated in a carbonaceous C matrix as shown by X-ray diffraction combined with Raman and X-ray photoelectron spectroscopies. These porous electrodes reveal enhanced stability during water oxidation as compared to planar samples at pH 4. Finally, their electrocatalytic performance depends on the geometric parameters and is optimized with 13 μm pore length, which yields 2.6 mA cm−2, or 49 A g−1, at η = 0.20 V.

Raman spectra of the different ecotoxicants such as perfluorooctane sulfonate acid, organotin compounds of different families tributyl-, and triphenyl-, as well as chemically close compounds belonging to the same family – such as mono-, di-, and tributyl organotin compounds were analyzed. The comprehensive Raman spectra analysis allowed suggesting the identification scheme for clear recognition of the toxins family and the following intra-group specification. Possibility of unambiguous toxins detection and identification was demonstrated also for complex mixtures of various toxins on a base of control of characteristic peak groups, which can be considered as Raman fingerprints of the listed environmentally hazardous substances.

Associated luminescence/plasmonic nanoparticles were prepared in a single step process as a result of laser illumination (low intensity CW He-Cd laser) of colloidal solution of YVO4:Eu3+@SiO2 mixed with heterometallic supramolecular complex. The results of SEM-EDX analysis, absorption, steady-state luminescence and luminescence decay measurements revealed formation of associated nanohybrids with core/shell morphology. The obtained nanostructures demonstrated metal enhanced luminescence with enhancement factor of 1.6. The theoretical calculations revealed strong correlation of enhancement factor and plasmonic nanoparticles number.

Nanotubular iron(III) oxide electrodes are optimized for catalytic proficiency in the water oxidation reaction at neutral pH. Nanostructured electrodes are prepared from anodic alumina templates coated with Fe2O3 by atomic layer deposition. Scanning helium ion microscopy, X-ray diffraction and Raman spectroscopy characterize the morphology and phase of samples submitted to various treatments. These methods document the contrasting effects of thermal annealing, on the one hand, and of electrochemical treatment, on the other hand. The electrochemical performance of the corresponding electrodes in dark conditions is quantified by steady-state electrolyses and electrochemical impedance spectroscopy. A rough and amorphous Fe2O3 with phosphate incorporation proves to be optimal in the water oxidation reaction. In combination with the ideal pore length L = 17 μm, the maximized catalytic turnover is reached with an effective current density J = 140 μA cm(-2) at 0.49 V applied overpotential η.

The dependence of the optic properties of niobium-phosphate glasses containing alkali metal oxides on their composition and structural features is investigated. Along with the increase of the niobium oxide content, a shift of the optic absorption boundary to the long-wavelength range and a substantial increase of the refraction index (from 1.50 to 1.73) are observed. The increase of the alkali metal mass results in the decrease of the refraction index and a shift to the short-wavelength range. The correlation between the length of polyphosphate groups and the type of alkali oxide is registered: the chain length increases from lithium to potassium.

Modification of Pechini method for synthesis of weakly agglomerated yttrium aluminum garnet powder has been presented. Modified synthesis procedure is based on an additional calcination process in KCl melt at 1000 °C and allows obtaining weaker agglomeration of nanoparticles. Structure, morphology and particle size have been defined using scanning electron microscopy technique, X-ray diffraction, and static light scattering. Adsorption ability of powders has also been studied. Diffraction patterns of samples confirm existence of only one YAG phase; the average size of particles is about 200 nm. The size of coherent-scattering regions was determined to be 40–50 nm. Steady-state luminescence properties and lifetimes of nanocrystalline YAG:Eu 3+ powders synthesized by standard and modified Pechini techniques were compared.

We investigate the effects of fabrication parameters on the properties of a self-assembled crystalline carbon-metal hybrid. We show that attenuation and geometrical parameters can be tuned, while high birefringence is observed for all studied cases.

The combination of oxide and heavier chalcogenide layers in thin film photovoltaics suffers limitations associated with oxygen incorporation and sulfur deficiency in the chalcogenide layer or with a chemical incompatibility which results in dewetting issues and defect states at the interface. Here, we establish atomic layer deposition (ALD) as a tool to overcome these limitations. ALD allows one to obtain highly pure Sb2S3 light absorber layers, and we exploit this technique to generate an additional interfacial layer consisting of 1.5 nm ZnS. This ultrathin layer simultaneously resolves dewetting and passivates defect states at the interface. We demonstrate via transient absorption spectroscopy that interfacial electron recombination is one order of magnitude slower at the ZnS-engineered interface than hole recombination at the Sb2S3/P3HT interface. The comparison of solar cells with and without oxide incorporation in Sb2S3, with and without the ultrathin ZnS interlayer, and with systematically varied Sb2S3 thickness provides a complete picture of the physical processes at work in the devices.

The combination of oxide and heavier chalcogenide layers in thin film photovoltaics suffers limitations associated with oxygen incorporation and sulfur deficiency in the chalcogenide layer or with a chemical incompatibility which results in dewetting issues and defect states at the interface. Here, we establish atomic layer deposition (ALD) as a tool to overcome these limitations. ALD allows one to obtain highly pure Sb2S3 light absorber layers, and we exploit this technique to generate an additional interfacial layer consisting of 1.5 nm ZnS. This ultrathin layer simultaneously resolves dewetting and passivates defect states at the interface. We demonstrate via transient absorption spectroscopy that interfacial electron recombination is one order of magnitude slower at the ZnS-engineered interface than hole recombination at the Sb2S3/P3HT interface. The comparison of solar cells with and without oxide incorporation in Sb2S3, with and without the ultrathin ZnS interlayer, and with systematically varied Sb2S3 thickness provides a complete picture of the physical processes at work in the devices.

Metal–carbon materials exhibiting surface-enhanced Raman scattering have been synthesized by laser irradiation of colloidal systems consisting of carbon and noble metal nanoparticles. The dependence of the Raman scattering intensity on the material composition and laser irradiation conditions has been investigated. The possibility of recording the Raman spectrum of organic dye rhodamine 6G, deposited in amount of 10–6 M on the substrate obtained from a colloidal solution is demonstrated.

The triphenyltin chloride (TPhTCl) molecular structure was investigated by Raman spectroscopy, surface-enhanced Raman spectroscopy (SERS) and the density functional theory (DFT) modeling. Several conformers with different ordering of the benzene rings were determined in the gas phase and in the dimethyl sulfoxide (DMSO) medium. It was shown that the dihedral angles describing such ordering can change under room conditions. Charge distribution of conformers was analyzed with the use of electrostatic potential (ESP) maps. The formation of weak hydrogen bonds and the rearrangement of the benzene rings to form a complex with negatively charged parts of other molecules were proven by ESP maps. Basing on the results of ESP map analysis, it can be assumed that interaction of TPhTCl molecule with metal cluster results in orientation ordering of the benzene rings. This conclusion was confirmed by modeling the atomistic and electronic structure of TPhTCl molecule adsorbed by the Au8 cluster, as well as by observing the intense SERS peaks assigned to vibrations of the benzene rings of TPhTCl molecule adsorbed on the surface of the gold inverse opals.

We present a new approach for the preparation of electrocatalytically active carbonaceous coatings embedding bimetallic nanoparticles (NPs) - AgPt@C structures, on surfaces with 2D and 3D geometry such as glass covered with indium tin oxide (ITO) film and anodic aluminum oxide substrates, respectively. We provide extensive characterization of the deposited structures and demonstrate their performance towards the electrocatalytic glucose oxidation, one half-reaction of biofuel cells. We observe that a preliminary surface treatment of the porous alumina substrate is essential for a homogeneous laser-induced deposition of AgPt@C nanoparticles across the whole pore depth.

In this work we report on YVO4 nanocrystalline powders doped with individual ions Nd3+, Er3+ and Tm3+, and their combination. Modified Pechini method allowed obtaining weakly agglomerated single phase nanoparticles with average size of 50 nm. Luminescence properties of single and triply doped YVO4 nanoparticles were studied under selective excitation via individual ions and combined excitation via host material. The obtained results demonstrated intra-centers energy transfer processes for the selective excitation, and set of luminescence bands corresponding to all lanthanides under host excitation in the triply doped system.

Until recently, planar carbonaceous structures such as graphene did not show any birefringence under normal incidence. In contrast, a recently reported novel orthorhombic carbonaceous structure with metal nanoparticle inclusions does show intrinsic birefringence, outperforming other natural orthorhombic crystalline materials. These flake-like structures self-assemble during a laser-induced growth process. In this article, we explore the potential of this novel material and the design freedom during production. We study in particular the dependence of the optical and geometrical properties of these hybrid carbon-metal flakes on the fabrication parameters. The influence of the laser irradiation time, concentration of the supramolecular complex in the solution, and an external electric field applied during the growth process are investigated. In all cases, the self-assembled metamaterial exhibits a strong linear birefringence in the visible spectral range, while the wavelength-dependent attenuation was found to hinge on the concentration of the supramolecular complex in the solution. By varying the fabrication parameters one can steer the shape and size of the flakes. This study provides a route towards fabrication of novel hybrid carbon-metal flakes with tailored optical and geometrical properties.

Photo-triggered release of biopharmaceutical drugs inside the cells is a challenging direction of modern science, which requires obtaining new polymeric systems. The interpolyelectrolyte complexes (IPECs) of poly-l-lysine with heparin capable of encapsulation of genetic constructions&mdash, such as model oligonucleotide, siRNA, and pDNA&mdash, were obtained. Poly-l-lysine to heparin ratios were optimized to provide the appropriate release kinetics of genetic material from the polyplex. In order to impart the obtained IPEC with photosensitive properties, the linker was synthesized as based on 4-brommethyl-3-nitrobenzoic acid. The conditions and kinetics of photosensitive linker destruction were carefully studied. The colloid particles of IPEC were modified with Cy3 probe and their cellular internalization was investigated by flow cytometry method. The efficacy of photosensitive IPECs as siRNA and pDNA delivery system was evaluated.

We investigate the effects of fabrication parameters on the optical properties of hybrid carbon metal flakes. We use a microscopic Muller matrix measurement technique to experimentally investigate different samples of carbon flakes. In all cases studied, the self-assembled metamaterial exhibited strong linear birefringence in the visible spectral range, while attenuation was found to be dependent on supra molecular complex density.

This chapter considers the problem of laser-matter interaction in the sense of laser-initiated chemical processes and subsequent formation of solid nanostructured materials. The main attention is focused to the effects originated as a result of laser impact onto heterogenic systems such as ‘solid-liquid’ interfaces, and in particular for the case when the chemical activity of the heterogenic system as a whole is mainly determined by the laser-induced effects in liquid phase. That is why all the issues connected to the laser ablation phenomena are out of the chapter scope. Heterogenic systems (substrate-solution interfaces) are extremely curious targets for the laser irradiation because of a much wider diversity of chemical processes as compared with homogeneous systems (solutions or solids). Another peculiarity of the selected system is the possibility of the chemical activity tuning by selecting either photochemical or thermochemical mode of laser exposure. This laser-induced approach proved to be efficient for one-step formation of the metal and hybrid metal-carbon nanostructures on the surface of the various kinds of substrates. The peculiarities of the laser-induced processes for the case of different solutions (electrolyte solutions or solutions of organometallic complexes) and different regimes of laser irradiation (thermal or photo-induced) are considered; as well as the possibility of the directed control of the composition of the deposited nanostructures is presented. It is important to note that the essential advantage of the laser-induced processes under discussion is the spatial control of the deposited structures that are formed in the laser-affected area of the substrate. The last circumstance together with well controlled composition and morphology ensure diverse functional properties of the laser-deposited nanostructures.

The position of activator ions in the lattice has a fundamental effect on the luminescent properties of phosphors. In this paper, we describe the normal and defect sites of Eu3+ ions in a Y2O3 crystal lattice, their interaction and difference in physical properties. Analytically detectable amounts of defect sites reached in Y2O3:Eu3+ nanopowders with an average size of 40–50 nm were synthesized by a novel combined Pechini-foaming method. The luminescence properties of Eu3+ ions in defect sites are most pronounced in highly doped nanocrystalline powders (32 and 40 at%). To explain this phenomenon we suggest the mechanism of irreversible energy transfer from normal to defect sites of Eu3+ ions.

We demonstrate a new approach which can be used for targeted imparting of plasmonic properties for a wide range of different substrates (transparent and non-transparent) which may have any 2D or 3D topological structure created independently in a prior step with some other technology.

Spectral studies are carried out and crystallization processes of niobium-containing phosphate glass with a high content of lithium oxide are studied for further research of the structural transformations in them caused by exposure to femtosecond laser radiation.

Femtosecond (fs) laser writing of two-dimensional microstructures (waveguides) is demonstrated in bulk phosphate glasses doped with silver ions. Silver-content phosphate and silver-content niobium–phosphate glasses with high concentration of silver oxide 55 mol% were used as samples for fs laser writing. The chemical network structure of the synthesized samples is analyzed through Raman spectroscopy and was found to be strongly sensitive to Nb incorporation. It was found that the direct laser writing process enables not only reorganization of glass network, but also formation of color centers and silver nanoparticles that are revealed in appearance of luminescence signal and plasmon absorption. The process of NPs' formation is more efficient for Nb-phosphate glass, while color centers are preferably formed in phosphate glass.

Nd3+-doped YVO4 nanophophors were prepared using modified Pechini method. Synthesized samples consist of large particles about 1 micron and weakly agglomerated nanoparticles with size about 200 nm. The effect of the doping concentration on the structure and luminescence was investigated. It was found that increase of Nd3+ concentration leads to the growth of unit cell parameters and red shift of Raman lines. Concentration dependence on the luminescence intensity was studied under different excitation wavelengths. Decay curves of 4F3/2–4I11/2 transition were observed for different doping concentration. Lifetime of excited level 4F3/2 was obtained from fitting.

Here we present a novel approach to the synthesis of hybrid Au–Ag/C nanoparticles (NPs) which were found to be carbon nanospheres containing dispersed Au–Ag bimetallic nanoparticles (1–5 nm). The Au–Ag/C NPs were obtained by laser-induced liquid phase deposition from solutions of supramolecular complex. It was revealed that subsequent annealing procedure of Au–Ag/C NPs at various temperatures over the range 100–600 °C allows variation and directed control of NPs’ morphology and composition (relative contents of principal components). For nanoscale carbon material the critical evaporation temperature was found to be about 300 °C, while for Ag and Au components – 500 °C and 600 °C accordingly. The morphology and composition variation makes possible tuning of the surface plasmon resonance characteristics that opens an efficient way of the NPs’ functional properties control, like for example Surface-Enhanced Raman Scattering (SERS). It was found that the obtained hybrid Au–Ag/C NPs display pronounced SERS activity with the enhancement factor (EF) ca. 105.

Hybrid nanostructures representing combinations of different materials and possessing properties that are absent in separate components forming the hybrid are discussed. Particular attention is given to hybrid structures containing plasmonic and magnetic nanoparticles, methods of their synthesis and the relationship between the composition, structure and properties. The functional features of the hybrid nanomaterials of various morphology (with core?shell structures, with encapsulated metal nanoparticles and with metal nanoparticles on the surface) are considered. The unique properties of these hybrid materials are demonstrated, which are of interest for solving problems of catalysis and photocatalysis, detecting impurities in various media, in vivo visualization, bioanalysis, as well as for the design of optical labels and multifunctional diagnostic nanoplatforms. The bibliography includes 182 references.

Nanoporous iridium electrodes are prepared and electrochemically investigated towards the water oxidation (oxygen evolution) reaction. The preparation is based on ‘anodic’ aluminum oxide templates, which provide straight, cylindrical nanopores. Their walls are coated using atomic layer deposition (ALD) with a newly developed reaction which results in a metallic iridium layer. The ALD film growth is quantified by spectroscopic ellipsometry and X‐ray reflectometry. The morphology and composition of the electrodes are characterized by scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, and X‐ray diffraction. Their catalytic activity is quantified for various pore geometries by cyclic voltammetry, steady‐state electrolysis, and electrochemical impedance spectroscopy. With an optimal pore length of L≈17–20 μm, we achieve current densities of J=0.28 mA cm−2 at pH 5 and J=2.4 mA cm−2 at pH 1. This platform is particularly competitive for achieving moderate current densities at very low overpotentials, that is, for a high degree of reversibility in energy storage.

Eu 3+ -doped YVO 4 nanopowders were prepared by the modified Pechini method. The structural properties were studied with XRD, SEM and Raman spectroscopy. XRD pattern indicates that nanocrystalline YVO 4 :Eu 3+ powders form only pure tetragonal phase. SEM images show that synthesized samples are mixture of large, well-faceted particles and weakly agglomerated nanoparticles. The symmetry of luminescent centers local surrounding was discussed in terms of asymmetry coefficient. Dependence of luminescent intensity on Eu 3+ doping concentration was studied at different excitation wavelengths. Lifetimes of 5 D 0 level were measured for all the synthesized nanopowders. Also the probabilities of radiative, nonradiative processes, and the radiative lifetimes were calculated.

Micro-chips based on organic-inorganic hybrid nanoparticles (NPs) composed of nanoalloys of gold (Au) and silver (Ag) embedded in an amorphous carbonaceous matrix (C-Au-Ag NPs) were prepared directly on a substrate by the laser-induced deposition (for short: LID) method. The C-Au-Ag NPs show a unique plasmon resonance which enhances Raman scattering of analytes, making the μ-chips suitable to detect ultra-low-volumes (10(-12) liter) and concentrations (10(-9) M) of bio-agents and a hazardous compound. These micro-chips constitute a novel, flexible solid-state device that can be used for applications in point-of-care diagnostics, consumer electronics, homeland security and environmental monitoring.

Nanocrystalline Eu3+-doped YAG powders were prepared by modified Pechini method. The structural properties were investigated with XRD, SEM and Raman spectroscopy. XRD pattern indicated that the phase-pure YAG:Eu3+ crystallites were obtained without the formation of any other phases. Raman spectrum revealed good homogeneity and crystallinity of synthesized nanopowders. The luminescent properties were studied by measurement of excitation and emission spectra, quantum yields and decay curves. The effect of Eu3+ concentration on 5D0 level lifetime was studied. The processes resulting in the relaxation of excited state (5D0 level) were discussed and the probabilities of radiative and nonradiative processes were calculated using the model of f–f transition intensities. It was found that the observed shortening of 5D0 level lifetime with Eu concentration is caused by increase of nonradiative process probability.

When we discuss the concept of laser-induced phenomena, we refer to several different processes such as laser ablation, optical breakdown, laser pyrolysis, and laser-induced reduction reactions. In our recent study, we discovered a new phenomenon, which can be called “laser-inspired chemical transformations”.

We present an original type of model electrode system consisting of bimetallic Au?Ag nanoparticles embedded in an amorphous carbon matrix with an extremely well-defined geometry of parallel, straight, cylindrical macropores. The samples are prepared in one step by direct laser deposition of the metal/carbon composite onto the inner walls of a porous 'anodic' alumina matrix serving as a template. The coating is homogeneous from top to bottom of the pores, and the amount of material deposited can be tuned by the duration of the deposition procedure. As a test system, we demonstrate that a bimetallic Ag?Au@C system is catalytically active for the electrochemical oxidation of glucose in alkaline solution, the anodic reaction of a direct glucose fuel cell. Furthermore, the electrocatalytic current density increases with the amount of Ag?Au@C NPs deposited, up to a point at which the pores are clogged with it. This type of model system allows for the systematic study of geometric effects in fuel cell electrodes. It can be generalized to a number of different nanoparticle compositions, and thereby, to various electrocatalytic reactions.

The synthesis of nanostructured metal–carbon materials by laser irradiation is an actual branch of laser physics and nanotechnology. Laser sources with different pulse duration allow to change the heating rate with realization of different transition scenarios and synthesis materials with various physical properties. We study the process of the formation of nanostructured metal–carbon clusters and complexes using laser irradiation of colloidal systems which have been consisted of carbon micro- nanoparticle and nanoparticle of noble metals. For carbon nanoparticle synthesis we use the method of laser ablation in liquid. For the realization of different regimes of laser surface modification of the target (glassycarbon and shungite) and the formation of micro- nanoparticle in a liquid the YAG:Nd laser with a pulse duration 0.5 ms up to 20 ms (pulse energy up to 50 J) was applied. We have used the CW-laser with moderate intensity in liquid (water or ethanol) for nanoparticle of noble metals synthesis. Thus, colloidal systems were obtained by using CW-laser with λ = 1.06 μm, I ~ 105–6 W/cm2, and t = 10 min. The average size of resulting particles was approximately about 10–100 nm. The nanoparticle obtaining was provided in the colloidal solution with different laser parameters. In this work we investigated the mechanism of the metal–carbon cluster formation during the process of colloidal system irradiation which has been consisted of separate carbon, silver and gold nanoparticles. This system was irradiated by nanosecond laser (100 ns) with average power up to 50 W.

In this work a method for the laser formation of C-Au-Ag clusters and complexes on the surface of an optically transparent media is discussed.

Synthesis of nanotructured metal-carbon materials by laser irradiation is an actual branch of laser physics and nanotechnology. Laser sources with different pulse duration allow changing the heating rate with realization of different transition scenarios and synthesis materials with various physical properties. We study the process of the formation of nanostructured metal-clusters and complexes using laser irradiation of colloidal systems which were consisted of carbon micro- nanoparticles and nanoparticles of noble metals. For carbon nanoparticles synthesis we use the method of laser ablation in liquid. For the realization of different regimes of laser surface modification of the target (glassycarbon and shungite) and the formation of micro- nanoparticles in a liquid the YAG:Nd laser with a pulse duration from 0.5 ms up to 20 ms (pulse energy up to 50J) was applied. We have used the CW-laser with moderate intensity in liquid (water or ethanol) for nanoparticle of noble metals synthesis. Thus, colloidal systems were obtained by using CW-laser with λ = 1.06 μm, I ~ 10 5-6 W/cm 2 , and t = 10 min. The average size of resulting particles was approximately about 10 to 100 nm. The nanoparticle obtaining was provided in the colloidal solution with different laser parameters. In this work we have investigated the mechanism of the metal-carbon cluster formation during the process of irradiation of colloidal system which were consisted of separate carbon, silver and gold nanoparticles. This system was irradiated by nanosecond laser (100 ns) with average power up to 50W.

The methods of laser ablation of chemical compounds in a liquid medium and in vacuum used for the production of highly dispersed materials and films, respectively, are considered. Features and advantages of these methods are noted and the potential of their application for the design of novel materials is discussed. Examples of application of these methods in scientific research are given. The bibliography includes 177 references.