فهرس المقالات methanol oxidation

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  1 - Platinium-Ruthenium electrocatalyst as sensor electrode for methanol oxidation
  Mohammad Yari Sajjad Sedaghat
  Hybrid nanocomposites of binary Pt-Ru/Polyaniline were prepared by oxidative polymerization of aniline andformation Pt and Ru nanoparticles. The polymerization of aniline was carried out in the presence of Potassiumhexa cyano Platinate (IV) and Ruthenium (III) nitrosyl أکثر

  Hybrid nanocomposites of binary Pt-Ru/Polyaniline were prepared by oxidative polymerization of aniline andformation Pt and Ru nanoparticles. The polymerization of aniline was carried out in the presence of Potassiumhexa cyano Platinate (IV) and Ruthenium (III) nitrosyl nitrate as oxidizing agents. During the reaction anilinemonomers undergo oxidation and form polyaniline (PANi) whereas the reduction of cations, result thefomiation of Pt and Ru nanoparticles. Nano-sized Pt and Ru particles were prepared by controlled reduction ofprecursors in micro emulsion medium, stabilized with the Sodium Dodecyl Sulfate. Micro emulsion solutionacts as both emulsifier and dopant to obtain stable nanocomposite. Pt-Ru/PAn nanocomposites are characterizedby cyclic voltammetry (CV). FT-IR spectroscopy and scarmine microelectronic microscopy (SEM). تفاصيل المقالة
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  2 - Synthesis and characterization of Pt3Co bimetallic nanoparticles supported on MWCNT as an electrocatalyst for methanol oxidation
  Mohammad Hossein Nobahari Ahmad Nozad Golikand Mojtaba Bagherzadeh
  The impregnation method was used to synthesize Pt and Pt3Co supported on MWCNTs applying NaBH4 as the reducing agent. The structure, morphology, and chemical composition of the electrocatalysts were characterized through SEM, XRD, and EDX. X-ray diffraction showed a goo أکثر

  The impregnation method was used to synthesize Pt and Pt3Co supported on MWCNTs applying NaBH4 as the reducing agent. The structure, morphology, and chemical composition of the electrocatalysts were characterized through SEM, XRD, and EDX. X-ray diffraction showed a good crystallinity of the supported Pt nanoparticles on the composites and showed the formation of Pt3Co alloy. The SEM images revealed that the particles of Pt3Co were deposited uniformly on the surface of MWCNT with a diameter of 10 nm. EDX analysis confirmed the surface segregation of Co and Pt occurred (1:3 surface atomic ratio Pt-Co) for the Pt3Co/MWCNT nanocomposite. The Pt3Co/MWCNTs and Pt/MWCNTs electrocatalysts’ electrochemical performance was assessed against the methanol oxidation reaction (MOR) in 0.5 M H2SO4 solution using the chronoamperometry (CA) and the cyclic voltammetry (CV) methods. The minimum onset potential and the largest oxidation current density were obtained at Pt3Co/MWCNTs electrocatalyst. The Pt3Co/MWCNT catalyst with a good alloying degree has been shown to have better anti-poisoning ability, electrochemical activity, and long-term durability than Pt/MWCNT catalysts, approved by the bimetallic catalysts’ bi-functional mechanism. تفاصيل المقالة
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  3 - Propane Oxidative Dehydrogenation on BiP1-xVxO4 Supported Titania Catalysts
  Mbarka Ouchabi Loulidi Ilyasse Mahfoud Agunaou
  10.30495/ijc.2022.1971843.1970
  The molecularly dispersed BiP1-xVxO4/TiO2 supported materials, with x varying from 0 to 1, were prepared by impregnation of Bismuth, Phosphorus, and Vanadium on a Titanium Oxide TiO2 support. Their structures were characterized by different techniques including X-ray di أکثر

  The molecularly dispersed BiP1-xVxO4/TiO2 supported materials, with x varying from 0 to 1, were prepared by impregnation of Bismuth, Phosphorus, and Vanadium on a Titanium Oxide TiO2 support. Their structures were characterized by different techniques including X-ray diffraction, Spectroscopic Raman, temperature-programmed reduction of the catalysts in H2 (H2-TPR), and by the methanol oxidation reaction. This very sensitive technique provided us with relevant information on the nature of the catalytic active sites (acid-base and redox) of the phases dispersed on the support. The characterization results show the structural evolution of BiP1-xVxO4 species, from isolated BiPO4 crystallites for x =0, to BiVO4 crystallites x =1. The oxidation of methanol showed the acidic properties of the BiPO4/TiO2 catalyst, through the formation of dimethyl ether as the major product of the reaction. The substitution of phosphorus by vanadium promotes the formation of formaldehyde, confirming the presence of redox sites. These catalysts were examined in the oxidative dehydrogenation (ODH) of propane to propene. For x > 0.5, dispersed BiVO4 exhibited higher levels of propane ODH than BiPO4 crystallites, consistent with their greater reducibility probed by temperature-programmed reduction of H2 and the presence of redox sites confirmed by methanol oxidation, with good selectivity to propene. Catalysts with x = 0, were less selective to propene due to favorable propylene combustion during its formation. A thorough understanding of the intrinsic catalytic properties of the BiP1-xVxO4/TiO2 oxides and in particular the BiPO4 and BiVO4 crystallites provides relevant information on the structural requirements of the propane ODH reaction, of interest for the design of more efficient Bi-P-V-O based catalysts for propene production. The results show that all substituted catalysts exhibit significant propene selectivity. In addition, the BiP0.7V0.3O4/TiO2 catalyst exhibits high activity with good propene selectivity. This catalytic activity was correlated with high reducibility. تفاصيل المقالة