A Combined Rotating Disk Electrode/X-ray Diffraction Study of Co Dissolution from Pt1-xCox Alloys

Pt/C and Pt/SnOx/C catalysts were synthesized using the polyol method. Their structure, morphology and chemical composition were studied using a scanning electron microscope equipped with an energy dispersive X-ray spectrometer, transition electron microscope and X-ray photoelectron spectroscope. Electrochemical measurements were based on the results of rotating disk electrode (RDE) experiments applied to ethanol electrooxidation. The quick evaluation of catalyst activity, electrochemical behavior, and an average number of transferred electrons were made using the RDE technique. The usage of SnOx (through the carbon support modification) in a binary system together with Pt causes a significant increase of the catalyst activity in ethanol oxidation reaction and the utilization of ethanol.

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Oxygen Reduction Reaction on Carbon Supported Ruthenium-Based Electrocatalysts in PEMFC

Materials Science Forum ◽

10.4028/www.scientific.net/msf.675-677.97 ◽

2011 ◽

Vol 675-677 ◽

pp. 97-100

Author(s):

He Xiang Zhong ◽

Hua Min Zhang ◽

Mei Ri Wang

Keyword(s):

Metal Carbonyl ◽

Rotating Disk ◽

Reduction Reaction ◽

Rotating Disk Electrode ◽

X Ray Diffraction ◽

Promising Alternative ◽

X Ray ◽

Transmission Electron ◽

High Resolution Tem ◽

Pt Electrocatalysts

The ruthenium-based electrocatalysts supported on carbon black were prepared by the decarbonylation of the transition metal carbonyl with the 1,6-hexanediol as the solvent. The catalysts were characterized via X-ray diffraction (XRD), transmission electron microscopy (TEM) and high resolution TEM (HRTEM). The electrochemical behaviours of the catalysts were investigated by cyclic voltammetry (CV) and rotating disk electrode (RDE) measurements in 0.5 M H2SO4 solution. The catalysts demonstrate attractive catalytic activity towards the ORR. The catalyst is expected to be promising alternative non-Pt electrocatalysts for PEMFC.

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Oxygen Reduction Studies on Carbon-supported Pt-M Catalysts (M: Ru, W, Mo)

Journal of New Materials for Electrochemical Systems ◽

10.14447/jnmes.v15i3.57 ◽

2012 ◽

Vol 15 (3) ◽

pp. 137-143 ◽

Cited By ~ 1

Author(s):

R. Hernández Maya ◽

A.J. Armenta González ◽

O. Ugalde ◽

M.T. Oropeza Guzmán ◽

P. Roquero

Keyword(s):

Oxygen Reduction ◽

Bimetallic Catalysts ◽

Rotating Disk ◽

Reduction Reaction ◽

Rotating Disk Electrode ◽

Molybdenum Oxides ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Catalytic Performances

The activities of a series of carbon-supported bimetallic catalysts, with different active phases loadings, were tested towards the oxygen reduction reaction (ORR). Pt was used in all materials and its loading was kept constant. Mo, W and Ru were used as promoting phases. Rotating Disk electrode experiments revealed that Pt-Ru displayed the best performance in oxygen reduction among the studied materials. The materials with the highest loadings of the second metal revealed the highest activities. X-Ray Diffraction studies (XRD) and Transmission Electron Microscopy (TEM) revealed the presence of homogeneously dispersed metallic ruthenium and different tungsten or molybdenum oxides in the corresponding catalysts. No evidence of alloying was found, and thus the catalytic performances appear to be related to the distribution and interaction of the active phases.

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Structure Characterization of Ni/Al2O3 Composite Coatings Prepared by Electrodeposition

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.163.64 ◽

2010 ◽

Vol 163 ◽

pp. 64-67 ◽

Cited By ~ 10

Author(s):

Anna Góral ◽

E. Bełtowska-Lehman ◽

P. Indyka

Keyword(s):

Composite Coatings ◽

Diffraction Method ◽

Rotating Disk ◽

Rotating Disk Electrode ◽

Structure Characterization ◽

X Ray Diffraction ◽

X Ray ◽

Pole Figures ◽

Steel Substrates

In the present study, the electrodeposition of composites consisted of metal matrix (nickel) and inert particles (hard nano-sized Al2O3 oxide) has been carried out in a Watt’s type bath of pH 4, at room temperature in a system with the steel rotating disk electrode. The influence of dispersed Al2O3 powder on structure characteristics (morphology, phase composition, texture, residual stresses) of Ni/Al2O3 coatings has been investigated. The crystallographic texture of Ni and Ni/Al2O3 coatings deposited on the steel substrates was analyzed by XRD technique based on the back-reflection pole figures. The “sin2ψ” X-ray diffraction method was used to determine the residual stress as a function of X-ray penetration depth. The influence of Al2O3 particles on the value of the Ni coating microhardness was also analyzed.

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Solid-Solutions as Supports and Robust Photocatalysts and Electrocatalysts: A Review

Catalysis for Sustainable Energy ◽

10.1515/cse-2020-0002 ◽

2020 ◽

Vol 7 (1) ◽

pp. 8-28 ◽

Cited By ~ 1

Author(s):

Victor Charles ◽

Ikegwuonu P. Ebuka ◽

Ndepana A. Gaya

Keyword(s):

Solid Solutions ◽

Photoelectron Spectroscopy ◽

Rotating Disk ◽

Reduction Reaction ◽

Rotating Disk Electrode ◽

Cyclic Voltammograms ◽

X Ray Diffraction ◽

X Ray ◽

Support Materials ◽

Clear Explanation

AbstractSome solid solutions have been strongly utilized over the years as good materials for the synthesis of electrocatalysts and photoctalysts. Sometimes, they are used as supports in order to improve electrocatalytic and photocatalytic properties. We show various achievements of solid solutions as good electrocatalysts, and also, good electrocatalysts support materials in oxygen reduction reaction (ORR), hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Also, we demonstrate various works utilizing solid solutions as good photocatalysts, and good photocatalysts support materials in overall water splitting and carbon dioxide reduction. In all these reports, solid solutions proved to posses the necessary properties needed of any material as electrocatalysts and photocatalysts. In many cases, their use as catalysts supports recorded great improvements. X-ray photoelectron spectroscopy (XPS) was largely used to confirm the chemical environment of the results obtained, together with X-ray diffraction (XRD). In the electrochemical methods, cyclic voltammograms (CVA), chronoamperometry and rotating disk electrode (RDE), were also carried out. Linear sweep voltametry (LSV) curve was carried out in some cases to measure the current at a working electrode, and tables were shown for clear explanation. In addition, a photoluminescence spectrum (PL) was used to probe the electronic structure of the various solid solutions.

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