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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]

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]

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]

• 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]