The paper presents the results of experimental studies of a photoactive catalyst in the form of barium titanate fibers with deposited particles of nickel, platinum and gold. Barium titanate fibers ...were synthesized by the molten salt method. The obtained barium titanate fibers were studied by SEM, TEM, XRD, and Raman spectroscopy. Photocatalytic studies showed that barium titanate fibers with platinum nanoparticles are the most active of the three prepared Metal/BaTiO3 samples.
Carbon nanotube (CNT) arrays were fabricated on Ct-Me-N-(O) alloys with content of Ct in the range of 6–40 at.% by chemical vapour deposition. The Ct was a catalytic metal from the group of the ...following elements: Ni, Co, Fe, Pd, while Me was a transition metal from the group of IV–VII of the periodic table (where Me=Ti,V, Cr, Zr, Nb, Mo, Ta, W, Re). Carbon nanotubes were found to grow efficiently on the alloy surface with its composition containing Ti, V, Cr, Zr, Hf, Nb or Ta. The growth of CNTs was not observed when the alloy contained W or Re. Additions of oxygen and nitrogen in the alloy facilitated the formation of oxynitrides and catalyst extrusion on the alloy surface. Replacement of the metals in alloy composition affected the diameter of the resulting CNTs. The obtained results showed that the alloy films of varying thickness (10–500nm) may be used for the CNTs growth. The resulting CNT material was highly homogenous and its synthesis reproducible.
This study demonstrates the ability to control the properties of TiO
-CuO
composite layers for photocatalytic applications by using a simple electrophoretic deposition method from isopropanol-based ...suspension. To obtain uniform layers with a controlled composition, the surfactant sodium lauryl sulfate was used, which influenced the electrophoretic mobility of the particles and the morphology of the deposited layers. The TiO
-CuO
composite layers with different CuO
contents (1.5, 5.5, and 11 wt.%) were obtained. It is shown that the optical band gap measured by UV-VIS-NIR diffuse reflectance spectra. When CuO
is added to TiO
, two absorption edges corresponding to TiO
and CuO
are observed, indicating a broadening of the photosensitivity range of the material relative to pure TiO
. An open-circuit potential study shows that by changing the amount of CuOx in the composite material, one can control the ratio of free charge carriers (n and p) and, therefore, the catalytic properties of the material. As a result, the TiO
-CuO
composite layers have enhanced photocatalytic activity compared to the pure TiO
layer: methanol yield grows with increasing CuO
content during CO
photoreduction.
This study demonstrates the ability to control the properties of TiOsub.2–CuOsub.x composite layers for photocatalytic applications by using a simple electrophoretic deposition method from ...isopropanol-based suspension. To obtain uniform layers with a controlled composition, the surfactant sodium lauryl sulfate was used, which influenced the electrophoretic mobility of the particles and the morphology of the deposited layers. The TiOsub.2–CuOsub.x composite layers with different CuOsub.x contents (1.5, 5.5, and 11 wt.%) were obtained. It is shown that the optical band gap measured by UV–VIS–NIR diffuse reflectance spectra. When CuOsub.x is added to TiOsub.2, two absorption edges corresponding to TiOsub.2 and CuOsub.x are observed, indicating a broadening of the photosensitivity range of the material relative to pure TiOsub.2. An open-circuit potential study shows that by changing the amount of CuOx in the composite material, one can control the ratio of free charge carriers (n and p) and, therefore, the catalytic properties of the material. As a result, the TiOsub.2–CuOsub.x composite layers have enhanced photocatalytic activity compared to the pure TiOsub.2 layer: methanol yield grows with increasing CuOsub.x content during COsub.2 photoreduction.
Monometallic iron supported catalysts were prepared by the impregnation method and tested in Fischer–Tropsch (F–T) synthesis. The activity tests performed in the studied reaction showed that the ...composition of the catalyst strongly influences the reactivity of the catalytic systems in the F–T reaction. It was also found that the system which showed the highest content of iron species on the catalyst surface exhibited the highest yield in F–T reaction. In addition, the most active catalyst also showed high specific surface area, high total acidity value and the highest amount of iron species on the catalyst surface. The analysis of the liquid product of F–T synthesis confirmed the occurrence of aliphatic, branched and unsaturated linear hydrocarbons.
In current paper formation method of anodic titania on a Ni-Ti alloy thin-film followed by multi-walled carbon nanotubes growth on the anodic oxide surface by CVD method using acetylene gas at 550°C ...for 2 minutes were demonstrated. The results of SEM, TEM, and Auger spectroscopy studies on obtained TiO2-CNT based composite material are shown. The possibility of vertical CNT growth on the anodic titania without introducing any additional catalyst layers which promote CNT growth are demonstrated. This work was supported by the Russian Science Foundation (Project № 16-19-10625).
Monometallic Ni and bimetallic Pd–Ni catalysts supported on mono‐SnO2 and SnO2–Al2O3 binary oxide are prepared using a wet impregnation and subsequent impregnation method. The catalysts are tested in ...oxy‐steam reforming of methanol (OSRM) and characterized. The activity measurements show that palladium‐promoted nickel catalysts supported on SnO2–Al2O3 exhibit high activity, selectivity towards hydrogen formation, and stability. The effect of Pd on reducibility, surface acidity, and morphology of the Ni supported catalyst, as well as its catalytic properties in OSRM, are discussed in detail.
Highly stable and active catalytic systems for hydrogen production in oxy‐steam reforming of methanol are reported. Control of the physicochemical properties of the catalysts is shown to be vital to achieve high activity and hydrogen yield. Furthermore, promotion of nickel catalysts supported on binary oxides is shown to improve their reactivity.
The paper proposes a method for forming thin films of polyvinylidene fluoride using a 3D printer. The extrusion parameters of a filament based on PVDF with a diameter of 1.75 were established and the ...optimal characteristics for printing by 3D printer were selected (nozzle temperature, table temperature, feed rate). Studies have shown that the local polarization of a thin PVDF film is stable for 20 hours.
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