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Abstract: IR laser ablation of hexagonal titanium in vacuum leads to amorphization of ablated Ti particles and when carried out in gaseous carbon monoxide it proceeds as reactive ablation involving particles amorphization, oxidation and carbidation. The films deposited in vacuum and in the presence of CO were examined by Fourier transform infrared, Raman and X-ray photoelectron spectroscopy, X-ray and electron diffraction and electron microscopy. The Ti films become oxidized upon contact with air and the Ti/C/O films are composed of Ti–O, Ti–C and C–O bonds-containing structures with Ti in Ti2+–Ti4+ state and incorporating crystalline rutile and elemental carbon. The ablation in vacuum represents a new approach to amorphous titanium and it is judged that hot ablated Ti particles are modified by reactions with CO decomposition products into amorphous Ti oxycarbides which undergo rapid post-pulse amorphization. [Copyright &y& Elsevier]

Abstract: IR laser- and UV laser-induced ablation of titanium monoxide (TM) in hydrogen (50Torr) is compared to the same process induced in vacuum and shown to result in deposition of hydrated surface modified nanostructured titanium suboxide films. Complementary analyses of the films deposited in vacuum and in hydrogen by Fourier transform infrared, Raman and X-ray photoelectron spectroscopy, X-ray diffraction and electron microscopy allowed to determine different features of both films and propose a mechanism of surface modification of ejected particles, which involves hydrothermal reduction of TM and subsequent reactions of evolved water. The films exert good adhesion to metal and quartz surfaces and are hydrophobic in spite of having their surface coated with adsorbed water. [Copyright &y& Elsevier]

Abstract: Pulsed infrared laser-irradiation of titanium monoxide leads to ablation and when carried out in gaseous benzene (1–5Torr) to simultaneous dielectric breakdown of benzene into low molecular carbonaceous species which allow carbothermal reduction of ablated TiO x particles and their protection by carbonaceous shell. The deposited particles are characterized by Fourier transform infrared Raman and X-ray photoelectron spectroscopy and by electron microscopy and shown to be stable towards oxidation in air. The reported process can find use in protection of gas-phase produced reactive nanoparticles by carbon phase. [Copyright &y& Elsevier]

This paper is a continuation of a study focused on thermodynamic properties of isomeric and quasi -isomeric ionic liquids. In this work 5 novel ionic liquids were synthesized, namely 1-(2-(2-ethoxyethoxy)ethyl)-3-alkylimidazolium bis(trifluoromethylsulfonyl)imides, where alkyl stands for different C 5 substituents. These species were characterized as to their isobaric molar heat capacity and thermal stability. The results are discussed with respect to different substituent isomerism and compared with data from our previous work (Rotrekl, Fluid Phase Equilib. 2017) that reported on a similar group of isomeric ionic liquids, namely 1-butyl-3-alkylimidazolium bis(trifluoromethylsulfonyl)imides. Data analysis of the experimental heat capacites was carried out using a non-statistical approach of the mathematical gnostics. The conclusions drawn from the present work bring an insight into the fine structure-property relationship which is useful in the development of predictive tools as well as it direct applications such as in energy storage or thermal fluids development. [ABSTRACT FROM AUTHOR]

A flow supercritical fluid crystallization with and without modifier/s was applied to prepare nanocrystalline TiO 2 monoliths without subsequent thermal treatment. The effect of processing conditions (temperature, pressure, water concentration, type of modifier: water or ethanol and water) on the crystallization, texture and purity of TiO 2 was investigated. Gel blocks for processing were prepared by nitric acid-catalysed sol-gel synthesis. It was revealed that one- or multi-step processing by scCO 2 with modifier leads to direct crystallization of TiO 2 monoliths of anatase-brookite crystal structure even at mild processing temperature of 40 °C and 30 MPa. 15 wt.% of water was determined to be the optimal concentration of water in scCO 2 as a crystallization agent. Processing temperature affected the anatase and brookite crystallite-size. Processing pressure affected the crystallization and purity of monolithic TiO 2 . The pre-drying as well as the post-drying by scCO 2 at 40 °C visibly improved the solidity of TiO 2 monolith and stabilized brookite crystallites. [ABSTRACT FROM AUTHOR]

Nanostructured TiO 2 anatase thin films were directly prepared using supercritical carbon dioxide (scCO 2 ) modified by organic solvent and water in two step processing. Organic solvent used as scCO 2 modifier at 30 MPa and 40 °C in the first step of processing was in the second step changed to water with simultaneous temperature increase to 150 °C which caused anatase thin films crystallization. The effect of the type of modifier (water, methanol, ethanol and acetone), concentration of modifier (5–40 wt.%) in scCO 2 and the amount of scCO 2 (50–200 g) passed through the high pressure column as well as the type of substrate (soda-lime glass and monocrystalline Si) on microstructure and purity of TiO 2 thin films were examined in both steps of processing. The prepared thin films were characterized with respect to their (micro)structural properties by Raman spectroscopy as well as X-ray diffraction, to their wettability by contact angle measurements and to their morphology by high resolution transmission electron microscopy. [ABSTRACT FROM AUTHOR]

In spite of advanced research on functional colloidal inorganic nanoparticles and their reactivity, room temperature reactive interactions between two different colloids have remained challenging so far. Laser ablation of titanium monoxide and silicon monoxide in ethanol and water allows the generation of TiO-derived and SiO-derived colloidal nanoparticles which were characterized for their stability, size distribution and zeta potentials with dynamic light scattering and after evaporation of solvent examined for their morphology, chemical and phase composition by scanning electron microscopy, Raman spectroscopy, high resolution transmission electron microscopy and electron diffraction and small angle X-ray scattering. Aqueous and ethanolic TiO-derived colloids consist of anatase and monoclinic TiO, while ethanolic SiO-derived colloids are composed of crystalline and amorphous Si, nanocrystalline Si and SiO2 and aqueous SiO-derived colloids contain, in addition to these phases, a high pressure form of cristobalite. Simple room temperature mixing of ethanolic TiO- and SiO-derived colloids allows the formation of TiSi2, which is a case of so far unreported room temperature reactive interactions between two colloidal species. All colloids absorb solar light and act as photocatalysts for methylene blue degradation. These findings present a challenge for further search for feasible room-temperature reactions between distinct colloidal particles and open the potential for green synthesis of other desirable and hardly achievable phases. [ABSTRACT FROM AUTHOR]

Despite of several decades lasting extensive research of bioactive and bioresorbable glasses the systematic parametrization and determination of the key factors affecting porosity and thermomechanical characteristics still remains challenging. Here, we present silica-phosphate glasses, with the composition 70SiO 2 –20P 2 O 5 –(10- x)CaO– x TiO 2 (mol%; x = 0, 2.5, 5, and 7.5), prepared by sol-gel method and reinforced by titanium dioxide via titanium isopropoxide (TTIP) incorporation which demonstrated tunable variation of porosity from micro-to macro-region and superb mechanical integrity during the calcination process. The presence of 7.5 mol% TiO 2 promotes dimensional stability up to 1000 °C as investigated by thermomechanical analysis. The XRD showed the dominant presence of silicon phosphate [Si(P 2 O 7)], titanium phosphate [Ti(P 2 O 7)] and calcium phosphates [β-Ca(P 2 O 6) and γ- Ca 2 (P 2 O 7)]. The effect of TiO 2 doping on the multiscale morphology and porosity was investigated by means of SEM, MIP, μCT, N 2 adsorption and USAXS/SAXS. Increasing TiO 2 content leads to the formation of open porosity up to 70 vol% and drives the formation of a refined interconnected macroporosity of 2–30 μm. In contrast, mesoporosity with a dominance of 3–6 nm pores decreases in all samples with increasing TiO 2 content. USAXS/SAXS revealed an increase in primary particle size with increasing TiO 2 content which is in good agreement with the nitrogen physisorption analysis showing that microporosity decreases with increasing TiO2 content. [Display omitted] • The reinforcement of silica-phosphate glass with titanium dioxide via titanium isopropoxide. • The increasing TiO 2 content led to the formation of open porosity 70 vol%. • The presence of TiO 2 drives a formation of a fully interconnected framework at a macroscale. • Micro-/mesoporosity decreases with increasing TiO 2 content. • USAXS/SAXS profiles indicated the hierarchical morphology of sol-gel glasses. [ABSTRACT FROM AUTHOR]

The cleaning of particles from smooth and rough paper surfaces using a high-speed CO2 snow jet was investigated. The measurements included characterization of the jet properties, determination of the cleaning efficiency, and evaluation of any possible adverse effects. The method was compared with nitrogen jet cleaning and dry cleaning by commercial materials. The results showed that the CO2 snow jet is able to effectively remove particles from the paper surface and did not cause any observable degradation. The CO2 snow jet cleaning compared with the mechanical dry cleaning showed similar effectiveness without any adverse effects on the paper surface. It was proved that the CO2 snow technique is a suitable method for cleaning common types of paper materials. [ABSTRACT FROM AUTHOR]

A pulsed Nd : YAG laser ablation of FeS in water and ethanol produces FeS-derived colloidal nanoparticles that absorb onto immersed porous ceramic substrates and create solar-light photocatalytic surfaces. The stability, size distribution and zeta potential of the nanoparticles were assessed by dynamic light scattering. Raman, UV-Vis and XP spectroscopy and electron microscopy reveal that the sol nanoparticles have their outmost layer composed of ferrous and ferric sulphates and those produced in water are made of high-pressure orthorhombic FeS, cubic magnetite Fe3O4 and tetragonal maghemite γ-Fe2O3, while those formed in ethanol contain hexagonal FeS and cubic magnetite Fe3O4. Both colloids absorb solar light and their adsorption to porous ceramic surfaces creates functionalized ceramic surfaces that induce methylene blue degradation by daylight. The laser induced process thus offers an easy and efficient way for the functionalization of porous surfaces by photocatalytic nanoparticles that avoids aggregation in the liquid phase. The formation of an orthorhombic high-pressure FeS phase stable under ambient conditions is the first example of high-pressure structures produced by laser ablation in liquid without the assistance of an electric field. [ABSTRACT FROM AUTHOR]

Over the past few decades, detonation nanodiamonds (NDs) have gained increased attention due to their unique physicochemical properties. Various methods for preparation of ND suspensions have been introduced. This paper presents thermally annealed nanodiamonds dispersed via sonication and separated by centrifugation in deionized water and dimethylformamide in five weight concentrations ranging from 0.05 to 1 wt%. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) were applied to study the thermal behavior of NDs. Crystallographic properties of air-annealed and dispersed NDs were examined by means of X-ray diffraction (XRD). Nanodiamond dispersions were analyzed by static light scattering (SLS), dynamic light scattering (DLS), ultra-small- and small-angle X-ray scattering (USAXS/SAXS), and high-resolution transmission electron microscopy (HRTEM). SLS and DLS give similar results of ND− aggregates mean size between ~ 61 and 73 nm, regardless of solvent type and nanoparticle concentration. For dispersions with increasing concentrations of NDs, neither increased aggregate size nor different kinetics of separation during sonication and centrifugation were observed. USAXS/SAXS provided the aggregates size (2Rg) in the range from 57 to 65 nm and size of primary particles from 5.4 to 5.8 nm. HRTEM also showed presence of larger aggregates with tens of nanometers in size in both water and DMF dispersions, and size of primary particles ranging from 5.5 to 6 nm in very good agreement with SAXS. [ABSTRACT FROM AUTHOR]

• TFC membrane ages after exposure of hexane vapors and storage at dry conditions. • Membrane flux decreases while selectivity is improved for aged membrane. • Polarity of membrane surface is changed by a solvent wetting with various polarity. • Conventional solvent exchange drying causes regeneration of aged membrane. • Regenerated membrane shows the same permeation properties as the pristine membrane. Thin-film polyamide composite membrane (TFC) is a good representative model of highly permeable membrane. SEM analysis showed that TFC membrane structure is swelled by hexane vapors. Contrary, its porous structure collapsed when the used membrane is stored at dry conditions. The aging of membrane causes significant decrease of both hexane vapors and nitrogen permeances while the selectivity increases tenfold. The study is based on time influence and on wetting by various solvents. Methanol treatment opens and swells the pores of aged membrane. Furthermore, the transport and separation properties were studied after gradual wetting by mutually miscible solvents with decreasing polarity (methanol, isopropanol and hexane) that are commonly used for membrane drying. Surprisingly, this solvent exchange drying procedure leads to a regeneration of the TFC membrane. The regenerated membrane shows the same transport and separation properties as the pristine TFC membrane. [ABSTRACT FROM AUTHOR]

Highly polymorphic cobalt sulfide represents attractive material because of its unique electronic, optical, magnetic, mechanical and catalytic properties. Pulsed laser irradiation of a solid CoS2 target results in ablation and deposition of thin films on Ta and Cu substrate, which were analyzed using scanning electron microscopy, Raman and FTIR spectroscopy, X‐ray photoelectron spectroscopy, high resolution electron microscopy and electron diffraction. These complementary analyses revealed that the film on Ta consists of the parent cubic CoS2 whereas the film on Cu exhibits a multiphase structure containing the cubic CoS2 and cubic Co2CuS4. The ternary species is known as an active electrode material with relatively high energy density for electrochemical capacitors and proves interdiffusion events at the interface of copper and colliding CoS2 particles. Such facile and one‐step process represents the first example of the Co2CuS4 formation through ablative reactive deposition on unheated substrate and adds to very rare examples of reactive laser deposition of ablated metal sulfides on unheated surfaces. The CoS2‐based films deposited on Ta and the Co2CuS4‐based films deposited on Cu were examined for their catalytic effect in Fenton degradation of methylene blue (MB). Their efficiency to degrade MB is compared and discussed. Laser irradiation of CoS2 allows deposition of nanocrystalline CoS2 on Ta and reactive deposition of Co2CuS4 on Cu substrate. Bimetallic sulfide is formatted via interdiffusion events of hot Co/S particles colliding with Cu atoms which are incorporated into cubic lattice of original CoS2. CoS2 and Co2CuS4 films exhibit catalytic effect in terms of Fenton‐like degradation. [ABSTRACT FROM AUTHOR]

Abstract: All input experimental errors for membrane flux determination were analyzed. The overall error in pressure did not largely influence the determination of membrane flux. The main contribution to errors was ascribed to flow meters and membrane thickness. The choice of an optimal operational range for input parameters led to elimination of at least 2/3 of the theoretical relative error for subsequent evaluation of the permeability of individual species. This is especially valuable for low‐permeable membranes, whereas a very low relative theoretical error can be obtained in the case of highly permeable materials. [ABSTRACT FROM AUTHOR]

Silica-titania mixed oxides and composites have been broadly examined for their physical and catalytic properties, but titanium monoxide-silicon monoxide counterparts have yet drawn very little attention. Here we report that laser-induced processing of mixed silicon and titanium monoxides results in reactions yielding a nanostructured Ti/Si/O composite absorbing visible light. Changes in the composition of intimately mixed μm-sized particles of silicon monoxide (SiO) and titanium monoxide (TiO) induced by scanning of a cw CO laser beam along the TiO-SiO pellet surface were examined by FTIR and Raman spectroscopy, X-ray diffraction and electron microscopy. They are shown to consist in the evolution of TiO (rutile and anatase), titanium suboxides (TiO, TiO), silica and amorphous binary SiO, TiO and ternary SiTiO nano-phases which contain less or more O than SiO and TiO monoxides. These products are ascribed to concurrent silicothermal reduction of TiO and O-transfer between SiO and TiO due to interdiffusion of Si- and Ti-based species. These reactions taking place under transient localized heating are not inhibited by passivation shells around SiO and TiO particles. The laser-produced Ti/Si/O composite shows absorption band at 425 nm tailing up to 1100 nm. Its solar-light photocatalytic activity in decolorization of Methylene Blue is compared to that of the unheated SiO and TiO powders absorbing only in UV region. [ABSTRACT FROM AUTHOR]

Four activated carbons based on red mombin seeds, cocoa pod husk, the external part of mango pits, and coffee husk were prepared by chemical activation using zinc chloride. Adsorption isotherms of hydrogen measured by a volumetric method under supercritical conditions corresponding to the three temperature levels and the pressure up to ten bars were determined. The dependence of the adsorbed amount of hydrogen on equilibrium pressure was linear for all adsorption isotherms measured at ambient temperatures. The corresponding excess adsorption experimental data were fitted by Henry's adsorption isotherm with an excellent accordance. The Dubinin-Radushkevich adsorption isotherm was demonstrated to match the excess adsorption data at cryogenic temperatures with high accuracy. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A laser with an oven was used for a synthesis of nanocrystals, -wires and -rods. • Two unknown Yb-Si phases (monoclinical, fcc) were found both at 800 and 1000 °C. • Amorphous nanowires possess a resistivity close to a heavily doped silicon. Abstract Ytterbium silicide nanoobjects were synthetized using pulsed laser ablation in an oven at temperatures of 800 and 1000 °C. Ablation of divided target Si/Yb in a flow of Ar resulted in deposits which contained mostly ytterbium silicide nanowires, nanorods and nanoparticles. Single nanoparticles (800 °C) are identical with Yb 3 Si 5 alloy; nanorods possess both a monoclinic phase not corresponding to any known structure in the phase diagram Yb-Si and a face-centered cubic structure close to the pure Yb but with a high Si content. At the temperature of 1000 °C, the studied nanorods and nanowires decorated by nanocrystals are practically amorphous, whereas the structure of those nanocrystals is close to that of the nanorods with the face-centered cubic structure prepared at 800 °C. Nanowire (1000 °C) is a semiconductor with ρ = 132.9 Ω.cm at room temperature, which is comparable to a heavily doped silicon. [ABSTRACT FROM AUTHOR]

This study characterized laser-deposited CaTiO 3 coats on several substrates by electron microscopy, X-ray diffraction, and Raman spectra. The hydrolytic stability of such coats exposed to ambient air and immersed into culture and osteogenic media has been respectively assessed by X-ray photoelectron spectra and energy dispersive X-ray analysis. It is shown these coats on titanium and micro/nanostructured oxidic titanium are not stable in air and culture or osteogenic media where they undergo hydrolysis and Ca leakage. The role of this hydrolysis is assessed and discussed in terms of not yet acknowledged complexation of the developing TiO 2 surface with constituents of Dulbecco's Modified Eagle's medium. The effect of the deposited and additionally heated CT coatings on human mesenchymal stem cells is assessed regarding survival, proliferation and differentiation towards the osteogenic lineage in osteogenic medium. It is also stressed that the identified CaTiO 3 hydrolysis in air and aquatic media seriously impacts the interpretation of bioactivity and physicochemical, catalytic and photocatalytic properties of CaTiO 3 surfaces, which has not been yet admitted and led to erroneous conclusions in many previous studies. [Display omitted] • CaTiO 3 coats on titanium undergo hydrolysis in air and culture and osteogenic media. • DMEM culture medium is judged to effect bioactivity of CaTiO 3 /TiO 2 phases. • Annealing of CaTiO 3 coats enhances osteogenic differentiation of human MSCs. • Aqueous CaTiO 3 surfaces are not stable bio-carriers, catalysts, and photocatalysts. • Self-organized precipitation of DMEM on TiO 2 reflects complex solutes interactions. [ABSTRACT FROM AUTHOR]

This study characterized laser-deposited CaTiO 3 coats on several substrates by electron microscopy, X-ray diffraction, and Raman spectra. The hydrolytic stability of such coats exposed to ambient air and immersed into culture and osteogenic media has been respectively assessed by X-ray photoelectron spectra and energy dispersive X-ray analysis. It is shown these coats on titanium and micro/nanostructured oxidic titanium are not stable in air and culture or osteogenic media where they undergo hydrolysis and Ca leakage. The role of this hydrolysis is assessed and discussed in terms of not yet acknowledged complexation of the developing TiO 2 surface with constituents of Dulbecco's Modified Eagle's medium. The effect of the deposited and additionally heated CT coatings on human mesenchymal stem cells is assessed regarding survival, proliferation and differentiation towards the osteogenic lineage in osteogenic medium. It is also stressed that the identified CaTiO 3 hydrolysis in air and aquatic media seriously impacts the interpretation of bioactivity and physicochemical, catalytic and photocatalytic properties of CaTiO 3 surfaces, which has not been yet admitted and led to erroneous conclusions in many previous studies. [Display omitted] • CaTiO 3 coats on titanium undergo hydrolysis in air and culture and osteogenic media. • DMEM culture medium is judged to effect bioactivity of CaTiO 3 /TiO 2 phases. • Annealing of CaTiO 3 coats enhances osteogenic differentiation of human MSCs. • Aqueous CaTiO 3 surfaces are not stable bio-carriers, catalysts, and photocatalysts. • Self-organized precipitation of DMEM on TiO 2 reflects complex solutes interactions. [ABSTRACT FROM AUTHOR]

Highlights: [•] Agro-biogas upgrading. [•] Water–swollen membrane. [•] Carbon dioxide and hydrogen sulphide removal. [•] Membrane choice based on its basic characteristics. [Copyright &y& Elsevier]

Porous geopolymers have drawn widespread attention owing to the flexibility of the production processes and the diversity of their structural properties. This paper first investigates and describes the key parameters for the fabrication of ceramic foam based on a geopolymer mixture by impregnation using the replica technique. The influence of geopolymer mixture viscosity on total porosity, pore size and mechanical strength of leucite ceramic foams is evaluated. The accelerated solidification step at 70 °C was investigated using time-dependent viscoelastic parameters such as tan δ, G' and G". For the fabrication of highly porous ceramics based on the geopolymer mixture, the optimum viscosity ranges between 9 and 15 Pa.s at 100 s−1. Differential thermal analysis (DTA) and X-ray diffraction (XRD) indicated the crystallization of the main leucite phase at 1073.5 °C, during the thermal exposure up to 1300 °C. It has been revealed that ceramic foam with an open porosity of 76 to 79 vol% can be fabricated using a replica technique. Scanning electron microscopy (SEM) and X-ray micro-computed tomography (micro-CT) have confirmed interconnected macroporosity with an open pore size up to 2 mm. This study introduces a novel group of materials combining geopolymer chemistry and traditional production of ceramic foams. Unlabelled Image • Cellular ceramic foam derived from potassium-based geopolymer was fabricated by replica impregnation technique. • The shear-thinning rheological behavior is beneficial for the impregnation regardless of whether the viscosity increases. • The incorporation of chamotte has resulted in the increase of viscosity and improvement of mechanical integrity. • Predominantly leucite ceramic foam reached an open porosity of 79 vol% with an interconnected pore size up to 2 mm. [ABSTRACT FROM AUTHOR]

• Mo/O/S nanostructures were synthetized by MoO 3 evaporation in H 2 S. • Mo/O/S structure is close to MoS 2 , luminescence is almost identical with MoO 3 one. • Reaction proceeds consecutively as MoO 3 → MoO 3-x → Mo(S, O) intermediates → Mo/O/S. Nanostructured molybdenum oxysulfide layers were prepared via MoO 3 evaporation in H 2 S at 800 °C. Transmission and scanning electron microscopy (SEM, TEM) and UV/Vis spectroscopy revealed a nano- and microstructure nature of the layers. Despite the significant oxygen content (up to 30 at. %), the qualitative estimation of some analytical measurements (UV/Vis, Raman and X-ray photoelectron spectroscopy) showed a close link to MoS 2 structure. As the elemental ratio Mo:(O + S) was ≈2, most of the oxygen atoms substituted sulphur in MoS 2 structure. On the other hand, luminescence spectra addressed defects and a band gap structure similar to MoO 3. [ABSTRACT FROM AUTHOR]

To support the trend of a new green energy introduction in economics it has become urgent nowadays that more available and cheaper materials would substitute noble and/or expensive materials (Au, Ag, Pt, Pd, Ga ...). Therefore, we studied molybdenum oxynitride films due to their catalytic properties. Molybdenum oxynitride films were fabricated by sub-atmospheric chemical vapor deposition (SACVD). According to Raman spectroscopy, grown platelets possessed MoO 3 structure up to 12 at. % NH 3 in NH 3 /air mixture. With the increasing amount of NH 3 in the reaction atmosphere (16–25 at. % NH 3), the films became heterogeneous containing Mo 4 O 11 and MoO 2 suboxides. Nanostructures – nanorods, nanoribbons - developed gradually at those samples with highest concentrations of NH 3 in the atmosphere (25–33 at. % NH 3) whose structure was built by blocks of corner-sharing Mo-octaedra separated by double layers of edge-sharing Mo-octaedra, which was revealed by Electron Diffraction Tomography (EDT). X-ray Photoelectron Spectroscopy (XPS), similarly to Raman spectroscopy, showed a gradual rise of molybdenum suboxides with NH 3 increase in the atmosphere, which was indicated by the successive appearance of Mo6+ → Mo5+ → Mo4+ species. As N 1s XPS signal was fully overlapped by the Mo 3d 5/2 one, a new procedure of a standard selected was used for the estimation of the nitrogen content in the films. This material was capable of reducing water under illumination as found by Cycling Votammetry (CV). Image 1 • MoO x N y nanostructures (nanowires, -rods ...) were synthetized via SACVD. • A new, not reported crystallographic structure was found for some nanostructures. • XPS N content in Mo based material was quantified using a novel procedure. [ABSTRACT FROM AUTHOR]

As thermal energy storage becomes an increasingly important topic, good knowledge of properties of phase-change materials (PCM) is essential. Among other properties, a good PCM should show a large enthalpy of melting, reproducible melting/solidification cycles, and long-term thermal stability. Temperatures and enthalpies of fusion should be determined at a possibly large range of conditions to allow for a critical evaluation of the experimental data and assessment of the material application potential. In this work, imidazolium-based ionic liquids (ILs) with long alkyl chain substituents 1-hexadecyl-3-methylimidazolium chloride and 1-hexadecyl-3-methyl-imidazolium saccharinate were studied in view of their possible use as phase-change materials. Differential scanning calorimetry (DSC) and the heat-leak modulus (HLM) methods were used to determine the temperatures and the enthalpies of phase transitions in the studied ILs, enabling us to study the influence of the heating and cooling rates on the measured properties. Enthalpies of fusion near to or larger than 100 J·g−1 were found in the studied ionic liquids, making them promising candidates for thermal energy storage. Peaks corresponding to possible liquid crystalline phases in the DSC traces of 1-hexadecyl-3-methylimidazolium saccharinate were observed, pointing to more complex phase behaviour of the studied ionic liquids. Finally, to critically evaluate the experimental data measured in this work, methods based on mathematical gnostics were used. Repeatability of measurements and the degree of mutual agreement between the methods used in this work could thus be determined. • Two imidazolium-based ionic liquids, [C 16 C 1 im]Cl and [C 16 C 1 im][Sac] were studied. • Temperatures and enthalpies of phase transitions were measured by DSC and HLM methods. • The influence of the heating/cooling rate on the ionic liquid phase behaviour was studied. • Mathematical gnostics was used to critically assess the measured data. [ABSTRACT FROM AUTHOR]

Direct decomposition of nitric oxide (NO) proceeds over Co–Mn–Al mixed oxides promoted by potassium. In this study, answers to the following questions have been searched: Do the properties of the K-promoted Co–Mn–Al catalysts prepared by different methods differ from each other? The K-precipitated Co–Mn–Al oxide catalysts were prepared by the precipitation of metal nitrates with a solution of K2CO3/KOH, followed by the washing of the precipitate to different degrees of residual K amounts, and by cthe alcination of the precursors at 500 °C. The properties of the prepared catalysts were compared with those of the best catalyst prepared by the K-impregnation of a wet cake of Co–Mn–Al oxide precursors. The solids were characterized by chemical analysis, DTG, XRD, N2 physisorption, FTIR, temperature programmed reduction (H2-TPR), temperature programmed CO2 desorption (CO2-TPD), X-ray photoelectron spectrometry (XPS), and the species-resolved thermal alkali desorption method (SR-TAD). The washing of the K-precipitated cake resulted in decreasing the K amount in the solid, which affected the basicity, reducibility, and non-linearly catalytic activity in NO decomposition. The highest activity was found at ca 8 wt.% of K, while that of the best K-impregnated wet cake catalyst was at about 2 wt.% of K. The optimization of the cake washing conditions led to a higher catalytic activity. [ABSTRACT FROM AUTHOR]