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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.

Surfaces functionalized with metal nanoparticles (NPs) are of great interest due to their wide potential applications in sensing, biomedicine, nanophotonics, etc. However, the precisely controllable decoration with plasmonic nanoparticles requires sophisticated techniques that are often multistep and complex. Here, we present a laser-induced deposition (LID) approach allowing for single-step surface decoration with NPs of controllable composition, morphology, and spatial distribution. The formation of Ag, Pt, and mixed Ag-Pt nanoparticles on a substrate surface was successfully demonstrated as a result of the LID process from commercially available precursors. The deposited nanoparticles were characterized with SEM, TEM, EDX, X-ray diffraction, and UV-VIS absorption spectroscopy, which confirmed the formation of crystalline nanoparticles of Pt (3&ndash, 5 nm) and Ag (ca. 100 nm) with plasmonic properties. The advantageous features of the LID process allow us to demonstrate the spatially selective deposition of plasmonic NPs in a laser interference pattern, and thereby, the formation of periodic arrays of Ag NPs forming diffraction grating

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.

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.

Carbon-based and carbon–metal hybrid materials hold great potential for applications in optics and electronics. Here, a novel material made of carbon and gold–silver nanoparticles is discussed, fabricated using a laser-induced self-assembly process. This self-assembled metamaterial manifests itself in the form of cuboids with lateral dimensions on the order of several micrometers and a height of tens to hundreds of nanometers. The carbon atoms are arranged following an orthorhombic unit cell, with alloy nanoparticles intercalated in the crystalline carbon matrix. The optical properties of this metamaterial are analyzed experimentally using a microscopic Müller matrix measurement approach and reveal a high linear birefringence across the visible spectral range. Theoretical modeling based on local-field theory applied to the carbon matrix links the birefringence to the orthorhombic unit cell, while finite-difference time-domain simulations of the metamaterial relates the observed optical response to the distribution of the alloy nanoparticles and the optical density of the carbon matrix.

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.

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.

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.

Nanocrystalline Eu3+-doped Mg2SiO4 powders were prepared with combined Pechini-solid phase synthesis. The structural properties were investigated with XRD, SEM and Raman spectroscopy. XRD pattern indicated that Mg2SiO4:Eu3+ were obtained with formation of other phase: MgO. Raman spectrum revealed good homogeneity and crystallinity of synthesized nanopowders. The luminescence properties were studied with measurement of excitation and emission spectra and decay curves. The effect of Eu3+ concentration on 5D0 level lifetime was studied. Most probably, the observed shortening of 5D0 level lifetime with Eu3+ concentration is caused by increase of nonradiative process probability.

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.

We discuss the laser-induced fabrication and detailed structural and optical characterization of a novel carbon allotrope intercalated with bimetallic nanoclusters.