Facile solvothermal synthesis of Pt-Cu nanocatalyst with improved electrocatalytic activity toward methanol oxidation

A binary metal nanocatalyst of platinum and copper was synthesized using a facile solvothermal process (polyol method). The synthesized catalyst was characterized using energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The electrochemical performance of the synthesized carbon supported binary metal catalyst, Pt?Cu/?, toward methanol oxidation reaction was checked and then compared with the commercial Pt/C (ETEK) catalyst, using cyclic voltammetry and chronoamperometric techniques. The Pt?Cu/C catalyst was found to be cubic in shape with indentations on the particle surface, having platinum to copper atomic composition of 4:1, i.e., (Pt4Cu). The peak current density for Pt?Cu/C catalyst recorded as 2.3 mA cm-2 at 0.7 V (vs Ag/AgCl) and 50 mV s-1, was two times higher than the current density of the commercially available Pt/C catalyst (1.16 mA cm-2 at 0.76 V). Moreover, the Pt?Cu/C catalyst was found to be more durable than the commercial Pt/C catalyst, as the Pt?Cu/C retained 89 % of its initial current density, while the commercial Pt/C catalyst retained 65 % of its initial current density after 300 potential cycles.

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Carbon Supported Pt+Os Catalysts for Methanol Oxidation

Zeitschrift für Naturforschung B ◽

10.1515/znb-2002-0211 ◽

2002 ◽

Vol 57 (2) ◽

pp. 193-201 ◽

Cited By ~ 8

Author(s):

Gülsün Gökağaç ◽

Brendan J. Kennedy

Keyword(s):

Methanol Oxidation ◽

Photoelectron Spectroscopy ◽

Surface Composition ◽

Carbon Support ◽

Methanol Oxidation Reaction ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Metal Metal ◽

Metal Support

11% Pt/C, 10% Pt + 1%Os/C, 9% Pt + 2%Os/C, 8% Pt + 3%Os/C, 7% Pt + 4%Os/C, 6% Pt + 5%Os/C and 5%Pt + 6% Os/C catalysts have been prepared for methanol oxidation reaction. Transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction and cyclic voltammetry have been used to understand the nature of the species present in these catalysts. 7% Pt + 4% Os/C was the most active catalyst, while 8% Pt + 3% Os/C was the least active one. It is found that the metal particle size and distribution on the carbon support, the surface composition and the oxidation states of the metal particles, the metal-metal and metal support interactions are important parameters to define the activity of the catalyst.

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Effect of a Thermal Treatment on the Activity of Carbon-Supported Pt, Pt+W and Pt+Mo Electrocatalysts for Methanol Oxidation Reactions

Zeitschrift für Naturforschung B ◽

10.1515/znb-2001-1209 ◽

2001 ◽

Vol 56 (12) ◽

pp. 1306-1314 ◽

Cited By ~ 1

Author(s):

Gülsün Gökağaç ◽

Jean-Michel Leger

Keyword(s):

Methanol Oxidation ◽

Carbon Support ◽

Hydrogen Gas ◽

Methanol Oxidation Reaction ◽

Oxidation Reactions ◽

X Ray ◽

In Situ Ftir Spectroscopy ◽

Transmission Electron ◽

Heat Treated ◽

Thermally Treated

Abstract Previous studies on carbon supported Pt, Pt+W and Pt+Mo indicated that Pt+Mo was the most active electrocatalyst at low potentials and that Pt+W has similar properties as pure Pt in methanol oxidation. Those samples were thermally treated at 900 °C in a hydrogen gas atmosphere for 6 hours to observe the effect on metal particle sizes and on their distribution on carbon support. It was found that thermally treated Pt+Mo/XC-72 remains the most active catalyst at all potentials compared to the other heated samples. The heat treatment caused the sintering of small particles leading to a decrease in activity of the catalysts except Pt+Mo/XC-72. The heat treated samples were characterised by voltammetry, X-ray diffraction, transmission electron microscopy and energy dispersive X-ray analysis techniques. The methanol oxidation reaction was followed by in-situ FTIR spectroscopy to identify products and adsorbed species on the surface of electrode.

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A Comparative Study on Ternary Low-Platinum Catalysts with Various Constructions for Oxygen Reduction and Methanol Oxidation Reactions

NANO ◽

10.1142/s1793292016500818 ◽

2016 ◽

Vol 11 (07) ◽

pp. 1650081 ◽

Cited By ~ 2

Author(s):

Yan Ni Wu ◽

Hai Fu Guo ◽

Peng Hu ◽

Xiao Peng Xiao ◽

Zhao Wang Xiao ◽

...

Keyword(s):

Oxygen Reduction ◽

Methanol Oxidation ◽

Reduction Reaction ◽

Methanol Oxidation Reaction ◽

Core Shell ◽

Oxidation Reactions ◽

X Ray Diffraction ◽

Structured Catalyst ◽

Transmission Electron ◽

One Step

Three types of ternary low-platinum nanocatalysts, alloy PdPtIr/C, core–shell PdPt@PtIr/C and Pd@PtIr/C, have been prepared, and their catalytic behaviors toward methanol oxidation reaction (MOR)/oxygen reduction reaction (ORR) are comparatively investigated via cyclic voltammetry and chronoamperometry analysis in an acidic medium. Through a two-step colloidal technique, the synthesized core–shell structured catalyst PtPd@PtIr/C with alloy core and alloy shell show the best catalytic activity toward MOR and the best poisoning tolerance. The alloy PdPtIr/C catalyst prepared via a one-step colloidal technique exhibits the best performance toward ORR among the three catalysts. All the three catalysts are characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD) and other characterization techniques.

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The Electrolyte-Fuel Concentrations Effects on Direct Methanol Alkaline Fuel Cell (DMAFC) Through Non-Noble Metal Catalysts

Journal of Science and Application Technology ◽

10.35472/jsat.v5i1.388 ◽

2021 ◽

Vol 5 (1) ◽

pp. 25

Author(s):

Wika Atro Auriyani ◽

Djoni Bustan ◽

Sri Haryati

Keyword(s):

Fuel Cell ◽

Methanol Oxidation ◽

Current Density ◽

Potassium Hydroxide ◽

Oxidation Reaction ◽

Nickel Foam ◽

Methanol Oxidation Reaction ◽

Alkaline Fuel Cell ◽

Noble Metal Catalysts ◽

Direct Methanol

Most of the R&D on Direct Methanol Alkaline Fuel Cell (DMAFC) concentrates on electrode catalyst and appropriate electrolyte to improve the efficiency. Mostly, a Pt-based electrocatalyst was used. In this research, Nickel foam and membrane silver as non-noble metal catalysts were used in a square-shaped fuel cell stack of 15 x 15 cm in size. The ionic current in the Direct Methanol Alkaline Fuel Cell (DMAFC) was due to the conduction of hydroxide ions. Potassium hydroxide which plays an essential role in delivering hydroxide ions was used in this study. The electrolyte effect of potassium hydroxide was studied in different concentrations for the methanol oxidation reaction. Nickel foam and membrane silver were used for methanol oxidation reaction (MOR) and oxygen reduction reaction (ORR). 1 M, 3 M, 5 M concentration of potassium hydroxide and 0.5 M, 1 M, 2 M, 3 M, 4 M, 5 M of methanol as a fuel have been conducted. The highest maximum power density of 543.35 mW/cm2 was obtained at 2,331 mA/cm2 of current density using the 5 M KOH and 0,5 M fuel. At equimolar concentration between fuel-electrolyte mixture give the higher current density.

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PtRu, PtRuFe and PtRuNi alloy electrocatalysts decorated on composite support C-MWCNTs for direct methanol fuel cells

Vietnam Journal of Catalysis and Adsorption ◽

10.51316/jca.2022.014 ◽

2021 ◽

Vol 11 (1) ◽

pp. 94-98

Author(s):

Quan Dang Long ◽

An Nguyen Minh ◽

Vinh Thach Phuc ◽

Ngan Nguyen Thi Thanh ◽

Lil Owin Khưu ◽

...

Keyword(s):

Direct Methanol Fuel Cells ◽

Methanol Oxidation Reaction ◽

X Ray Diffraction ◽

X Ray ◽

Composite Support ◽

Transmission Electron ◽

Direct Methanol ◽

Co Reduction ◽

Alloy Catalysts ◽

Better Than

In this work, carbon Vulcan XC-72 (C) and carbon nanotubes (CNTs) supported ternary platinum-ruthenium-iron (PtRuFe) and platinum-ruthenium-nickel (PtRuNi) alloy nanoparticles have been synthesized by a co-reduction method. The catalyst samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and cyclic voltammetry (CV). The results show that ternary alloy catalysts are always better than binary alloy catalysts. In particular, PtRuNi is the best catalyst for methanol oxidation reaction.

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Synthesis of NiO/TiO2 sub-microrods as catalyst for methanol oxidation reaction

International Journal of Modern Physics B ◽

10.1142/s0217979220400020 ◽

2019 ◽

Vol 34 (01n03) ◽

pp. 2040002

Author(s):

Xiaoyu Yue ◽

Yixuan Wang ◽

Ting Zhang ◽

Wei Gao

Keyword(s):

Electron Microscopy ◽

Methanol Oxidation ◽

Oxidation Reaction ◽

Direct Methanol Fuel Cells ◽

Methanol Oxidation Reaction ◽

X Ray Diffraction ◽

Transmission Electron ◽

Potential Applications ◽

Direct Methanol ◽

Limited Oxygen

[Formula: see text] sub-microrods have been synthesized via a simple two-step route. First, the precursors were prepared by a facile ethylene glycol-mediated method; then, [Formula: see text] sub-microrods were obtained by a limited-oxygen atmosphere deriving from the decomposition of urea at [Formula: see text]C for 3 h in air. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS) and transmission electron microscopy (TEM). The obtained [Formula: see text] sub-microrods exhibit cubic NiO structure with high crystallinity and anatase [Formula: see text]. Both SEM and TEM show the typical sub-microrods with lengths of [Formula: see text] nm and diameters of [Formula: see text] nm. The uniform sub-microrods have great electrocatalytic performance for methanol oxidation reaction in alkaline solution. This material may have potential applications in direct methanol fuel cells.

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Preparation of Flower-Like Silica Microstructures

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.123-125.1295 ◽

2010 ◽

Vol 123-125 ◽

pp. 1295-1298

Author(s):

Wen Qi Wang ◽

Zhen Sheng Peng

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Transmission Electron Microscopy ◽

Silicon Oxide ◽

Silicon Monoxide ◽

Metal Catalyst ◽

X Ray ◽

Transmission Electron ◽

Silicon Silicon ◽

Scanning Electron

Novel flower-like silica microstructures have been synthesized through heating silicon, silicon monoxide and active carbon mixed powders under an H2/Ar (3%) atmosphere at 1050°C without assistance of any metal catalyst. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM) and energy dispersive x-ray spectrometer (EDS) analyses reveal that the wires are amorphous and consist only of silicon oxide, generated from the reaction of CO with SiC. A possible growth model based on both of vapor-solid (VS) and the Oxide-assisted growth (OAG) mechanism has been supposed here to explain this phenomenon.

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Electrochemical oxidation of methanol on Pt/(RuxSn1-x)O2 nanocatalyst

Journal of the Serbian Chemical Society ◽

10.2298/jsc130718091k ◽

2013 ◽

Vol 78 (11) ◽

pp. 1703-1716 ◽

Cited By ~ 1

Author(s):

Mila Krstajic ◽

Maja Obradovic ◽

Biljana Babic ◽

Velimir Radmilovic ◽

Uros Lacnjevac ◽

...

Keyword(s):

Electrochemical Oxidation ◽

Methanol Oxidation ◽

Pt Nanoparticles ◽

Atomic Ratio ◽

X Ray Diffraction ◽

Two Phase ◽

X Ray ◽

Oxidation Of Methanol ◽

Potentiodynamic Polarization Curves ◽

Transmission Electron

The Ru-doped SnO2 powder, (RuxSn1-x)O2, with the Sn:Ru atomic ratio of 9:1 was synthesized and used as a support for Pt nanoparticles (30 mass% loading). The (RuxSn1-x)O2 support and Pt/(RuxSn1-x)O2 catalyst were characterized by X-ray diffraction, energy dispersive X-ray spectroscopy and transmission electron microscopy (TEM). (RuxSn1-x)O2 was found to be two-phase material consisting of probably solid solution of RuO2 in SnO2 and pure RuO2. The average Pt particle size determined by TEM was 5.3 nm. Cyclic voltammetry of Pt/(RuxSn1-x)O2 indicated good conductivity of the sup-port and displayed usual features of Pt. The results of the electrochemical oxidation of COads and methanol on Pt/(RuxSn1-x)O2 were compared with those on commercial Pt/C and PtRu/C catalysts. Oxidation of COads on Pt/(RuxSn1-x)O2 starts at less positive potentials than on PtRu/C and Pt/C. Potentiodynamic polarization curves and chronoamperometric curves of methanol oxidation indicated higher initial activity of Pt/(RuxSn1-x)O2 catalyst compared to PtRu/C, but also a greater loss in the current density over time. Potentiodynamic stability test of the catalysts revealed that deactivation of the Pt/(RuxSn1-x)O2 and Pt/C was primarily caused by the poisoning of Pt surface by the methanol oxidation residues, which mostly occurred during the first potential cycle. In the case of PtRu/C the poisoning of the surface was minor and deactivation was caused by the PtRu surface area loss.

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Simulation Design and Device Characteristics of AlAs/GaAs/AlAs Resonant Tunneling Structures with a GalnAs Emitter Spacer Layer

MRS Proceedings ◽

10.1557/proc-240-627 ◽

1991 ◽

Vol 240 ◽

Author(s):

Y. W. Choi ◽

H. M. Kim ◽

C. R. Wie

Keyword(s):

Current Density ◽

Resonant Tunneling ◽

Conduction Band Edge ◽

Peak Current Density ◽

Peak Voltage ◽

Peak Current ◽

X Ray ◽

3 Dimensional ◽

Indium Composition ◽

Spacer Layer

ABSTRACTElectrical and structural investigation of AlAs/GaAs/AlAs resonant tunneling structures with pseudomorphic strained Ga1−xInxAs (x=0, 0.05, 0.1, 0.15, and 0.2) emitter spacer layer are presented. As indium composition increased, the peak current density, peak voltage, and peak to valley ratio increased. For a theoretical understanding of these increases, a self-consistent simulation was employed. In the simulation, we treated the 2-dimensional electrons confined in the low energy bandgap GalnAs emitter spacer well as pseudo-3-dimensional electrons, distributed continuously down to the emitter launching energy. In the simulation, we used the bottom energy of the pseudo-3-dimensional electrons to be ⅔δEc below the emitter conduction band edge. Using the above values, an excellent agreement of peak current density and peak voltage between the experiment and the simulation was achieved. Also, for structural identification, standard double crystal x-ray rocking curve technique has been used. From the interference analysis of the x-ray results, we could obtain the indium composition times thickness product.

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Partially Graphitized Iron-Carbon Hybrid Composite as Electrochemical Supercapacitor Material

10.26434/chemrxiv.11369673 ◽

2020 ◽

Author(s):

Sai Rashmi M. ◽

Ashish Singh ◽

Chandra sekhar Rout ◽

Akshaya Samal ◽

Manav Saxena

Keyword(s):

Iron Oxide ◽

Current Density ◽

Electrode Material ◽

High Performance ◽

Electrode Materials ◽

Carbon Composite ◽

X Ray ◽

Transmission Electron ◽

Excellent Property ◽

A Current

The conversion of biomass into valuable carbon composites as an efficient non-precious energy storage electrode material have elicited extensive research interest. As synthesized partially graphitized iron oxide-carbon composite material (Fe3O4/Fe3C@C) shows an excellent property as an electrode material for supercapacitor. X-ray diffraction, High resolution transmission electron microscopy, X-ray photo-electron spectroscopy and Brunauer-Emmett-Teller analysis is used to study the structural, compositional and surface areal properties. The electrode material shows a specific surface area of 827.4 m2/g. Due to the synergistic effect of graphitic layers with iron oxide/carbide, Fe3O4/Fe3C@C hybrid electrode materials display high-performance for supercapacitor with excellent capacity of 878 F/g at a current density of 5A/g (3-electrode) and 211.6 F/g at a current density of 0.4A/g (2-electrode) in 6M KOH electrolyte with good cyclic stability.

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