Reproducible Electrodeposition of Hydrogen Molybdenum Bronze Films and Electrochemical Reduction of Carbon Dioxide

Electrochemical synthesis of hydrogen bronze films including molybdenum, tungsten and vanadium are useful electrocatalytic films. This paper describes reproducible hydrogen molybdenum bronze film formation on indium tin oxide and carbon paper substrates by electrodeposition. Film formation is a kinetic process dependent on concentration, time and potential. Bulk electrolysis over time determined the dependence of film thickness on time of deposition. Once the films were prepared, the films were characterized by thickness, conductivity, XPS and X-Ray Diffraction. Cyclic voltammetry in dilute sulfuric acid confirmed that these films are not electrochromic. Hydrogen bronze films on conductive carbon paper were also prepared. Carbon dioxide bubbled into 0.5 M NaHCO3 using a hydrogen bronze film as the working electrode resulted in formate quantified by ion chromatography. Cyclic voltammetry and Tafel plots using the as deposited films in 0.5 M NaHCO3 saturated with CO2 showed catalytic activity toward reduction of carbon dioxide. A Farradaic efficiency of 8% was obtained with an applied potential of -0.4 V.

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Study of Structure and Electro-Optical Characteristics of Indium Tin Oxide Thin Films

Advances in Condensed Matter Physics ◽

10.1155/2013/408182 ◽

2013 ◽

Vol 2013 ◽

pp. 1-8 ◽

Cited By ~ 33

Author(s):

N. M. Khusayfan ◽

M. M. El-Nahass

Keyword(s):

Thin Films ◽

Indium Tin Oxide ◽

Annealing Temperature ◽

Electron Beam Evaporation ◽

X Ray Diffraction ◽

Air Atmosphere ◽

Light Region ◽

Ito Thin Films ◽

Predominant Orientation ◽

Deposited Films

ITO thin films were prepared by electron beam evaporation of ceramic ITO target. The films were subsequently annealed in air atmosphere at the temperatures 300°C and 600°C in order to improve their optical and electrical properties. The crystal structure and morphology of the films are investigated by X-ray diffraction and scanning electron microscope techniques, respectively. The films exhibited cubic structure with predominant orientation of growth along (222) direction, and the crystallite size increases by rising annealing temperature. Transparency of the films, over the visible light region, is increased by annealing temperature. The resulting increase in the carrier concentration and in the carrier mobility decreases the resistivity of the films due to annealing. The absorption coefficient of the films is calculated and analyzed. The direct allowed optical band gap for as-deposited films is determined as 3.81 eV; this value is increased to 3.88 and 4.0 eV as a result of annealing at 300°C and 600°C, respectively. The electrical sheet resistance is significantly decreased by increasing annealing temperature, whereas figure of merit is increased.

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Electrodeposition of Cu2O Particles by Using Electrolyte Solution Containing Glucopone as Surfactant

JURNAL ILMU FISIKA | UNIVERSITAS ANDALAS ◽

10.25077/jif.1.2.18-20.2009 ◽

2009 ◽

Vol 1 (2) ◽

pp. 18-20

Author(s):

Dahyunir Dahlan

Keyword(s):

Indium Tin Oxide ◽

Pulse Current ◽

Platinum Electrode ◽

Saturated Calomel Electrode ◽

X Ray Diffraction ◽

X Ray ◽

Glass Substrates ◽

Continuous Current ◽

Oxide Particles ◽

Cupric Sulphate

Copper oxide particles were electrodeposited onto indium tin oxide (ITO) coated glass substrates. Electrodeposition was carried out in the electrolyte containing cupric sulphate, boric acid and glucopone. Both continuous and pulse currents methods were used in the process with platinum electrode, saturated calomel electrode (SCE) and ITO electrode as the counter, reference and working electrode respectively. The deposited particles were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). It was found that, using continuous current deposition, the deposited particles were mixture of Cu2O and CuO particles. By adding glucopone in the electrolyte, particles with spherical shapes were produced. Electrodeposition by using pulse current, uniform cubical shaped Cu2O particles were produced

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Photochemical and Electrochemical Reduction of Carbon Dioxide Catalyzed by a Polyoxometalate-Organic Photosensitizer Complex

10.26434/chemrxiv.7177892 ◽

2018 ◽

Author(s):

Chandan Dey ◽

Ronny Neumann

Keyword(s):

Carbon Dioxide ◽

Cyclic Voltammetry ◽

Formic Acid ◽

Electrochemical Reduction ◽

Mass Spectroscopy ◽

Photochemical Reactions ◽

Reducing Agent ◽

Covalent Attachment ◽

Hybrid Complex ◽

Open Face

A manganese substituted Anderson type polyoxometalate, [MnMo6O24]9-, tethered with an anthracene photosensitizer was prepared and used as catalyst for CO2 reduction. The polyoxometalate-photosensitizer hybrid complex, obtained by covalent attachment of the sensitizer to only one face of the planar polyoxometalate, was characterized by NMR, IR and mass spectroscopy. Cyclic voltammetry measurements show a catalytic response for the reduction of carbon dioxide, thereby suggesting catalysis at the manganese site on the open face of the polyoxometalate. Controlled potentiometric electrolysis showed the reduction of CO2 to CO with a TOF of ~15 sec-1. Further photochemical reactions showed that the polyoxometalate-anthracene hybrid complex was active for the reduction of CO2 to yield formic acid and/or CO in varying amounts dependent on the reducing agent used. Control experiments showed that the attachment of the photosensitizer to [MnMo6O24]9- is necessary for photocatalysis.<div> </div>

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Nano-Folded Gold Electrocatalysts Enhance the Selectivity of Carbon Dioxide Reduction

10.26434/chemrxiv.8296193 ◽

2019 ◽

Author(s):

Kam Sang Kwok ◽

Yuxuan Wang ◽

Michael Cao ◽

Hao Shen ◽

Weinan Xu ◽

...

Keyword(s):

Carbon Dioxide ◽

Mass Transport ◽

Gold Film ◽

X Ray Diffraction ◽

Thin Gold Film ◽

Faradaic Efficiency ◽

X Ray ◽

Transmission Electron ◽

Carbon Monoxide Formation ◽

Catalytic Interfaces

The local structure and geometry of catalytic interfaces can influence the selectivity of chemical reactions. Here, using a pre-strained polymer, we uniaxially compress a thin gold film to form a nano-folded catalyst. We observe two kinds of folds and can tune the ratio of loose to tight folds by varying the extent of pre-strain in the polymer. We characterize the nano-folded catalysts using x-ray diffraction, scanning, and transmission electron microscopy. We observe grain reorientation and coarsening in the nano-folded gold catalysts. Electroreduction of carbon dioxide with these nano-folded catalysts reveals an enhancement of Faradaic efficiency for carbon monoxide formation by a factor of about four. This result suggests that electrolyte mass transport limitations and an increase of the local pH in the tight folds of the catalyst outweigh the effects of alterations in grain characteristics. Together, our studies demonstrate that nano-folded geometries can significantly alter grain characteristics, mass transport, and catalytic selectivity.

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Hydrophobic Ferrocene Derivatives as Potential Standards in Electrochemistry

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19970185 ◽

1997 ◽

Vol 62 (2) ◽

pp. 185-198 ◽

Cited By ~ 6

Author(s):

Jaroslav Podlaha ◽

Petr Štěpnička ◽

Róbert Gyepes ◽

Vladimír Mareček ◽

Alexander Lhotský ◽

...

Keyword(s):

Surface Tension ◽

Cyclic Voltammetry ◽

Redox Potential ◽

Diffusion Coefficients ◽

Carbon Electrodes ◽

X Ray Diffraction ◽

Ferrocene Derivatives ◽

X Ray ◽

Special Cases ◽

As Solubility

Ferrocene (FcH) derivatives monosubstituted by palmitoyl (1), hexadecyl (2), 1-adamantoyl (3) or 1-adamantylmethyl (4) groups were sythesized and characterized by NMR, mass and 57Fe Mossbauer spectroscopy. The structure of 1-adamantoylferrocene was determined by single-crystal X-ray diffraction. Cyclic voltammetry on gold and glass-like carbon electrodes demonstrated that the compounds can serve as electrochemical standards for special cases since their ferrocene/ferricinium redox potential remains stable and reversible, while the properties such as solubility, diffusion coefficients and surface tension are strongly solvent-dependent.

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Surface Stoichiometry and Depth Profile of Tix-CuyNz Thin Films Deposited by Magnetron Sputtering

Materials ◽

10.3390/ma14123191 ◽

2021 ◽

Vol 14 (12) ◽

pp. 3191

Author(s):

Arun Kumar Mukhopadhyay ◽

Avishek Roy ◽

Gourab Bhattacharjee ◽

Sadhan Chandra Das ◽

Abhijit Majumdar ◽

...

Keyword(s):

Magnetron Sputtering ◽

Photoelectron Spectroscopy ◽

Film Surface ◽

Grazing Incidence ◽

X Ray Diffraction ◽

X Ray ◽

Relative Composition ◽

Transmission Electron ◽

Deposited Film ◽

Deposited Films

We report the surface stoichiometry of Tix-CuyNz thin film as a function of film depth. Films are deposited by high power impulse (HiPIMS) and DC magnetron sputtering (DCMS). The composition of Ti, Cu, and N in the deposited film is investigated by X-ray photoelectron spectroscopy (XPS). At a larger depth, the relative composition of Cu and Ti in the film is increased compared to the surface. The amount of adventitious carbon which is present on the film surface strongly decreases with film depth. Deposited films also contain a significant amount of oxygen whose origin is not fully clear. Grazing incidence X-ray diffraction (GIXD) shows a Cu3N phase on the surface, while transmission electron microscopy (TEM) indicates a polycrystalline structure and the presence of a Ti3CuN phase.

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Studies on electrooxidation of lignin and lignin model compounds. Part 1: Direct electrooxidation of non-phenolic lignin model compounds

Holzforschung ◽

10.1515/hf.2011.069 ◽

2012 ◽

Vol 66 (3) ◽

Cited By ~ 1

Author(s):

Takumi Shiraishi ◽

Toshiyuki Takano ◽

Hiroshi Kamitakahara ◽

Fumiaki Nakatsubo

Keyword(s):

Electron Transfer ◽

Cyclic Voltammetry ◽

Carbonyl Compounds ◽

Model Compounds ◽

Lignin Model Compounds ◽

Bulk Electrolysis ◽

Lignin Model ◽

Dimeric Compound ◽

High Yields ◽

Short Time

Abstract The direct anodic oxidation of non-phenolic lignin model compounds was investigated to understand their basic behaviors. The results of cyclic voltammetry (CV) studies of monomeric model, such as 1-(4-ethoxy-3-methoxyphenyl)ethanol, are interpreted as the oxidation for Cα-carbonylation did not proceed in the reaction without a catalyst, but a base promotes this reaction. Indeed, the bulk electrolyses of the monomeric lignin model compounds with 2,6-lutidine afforded the corresponding Cα-carbonyl compounds in high yields (60–80%). It is suggested that deprotonation at Cα-H in the ECEC mechanism (E=electron transfer and C=chemical step) is important for Cα-carbonylation. In the uncatalyzed bulk electrolysis of a β-O-4 model dimeric compound, 4-ethoxy-3-methoxyphenylglycerol-β-guaiacyl ether, the corresponding Cα-carbonyl compound was not detected but as a result of Cα-Cβcleavage 4-O-ethylvanillin was found in 40% yield. In the electrolysis reaction in the presence of 2,6-lutidine (as a sterically hindered light base), the reaction stopped for a short time unexpectedly. These results indicate the different electrochemical behavior of simple monomeric model compounds and dimeric β-O-4 models. The conclusion is that direct electrooxidation is unsuitable for Cα-carbonylation of lignin.

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Single Crystal X-ray Diffraction Studies of Carbon Dioxide and Fuel-Related Gases Adsorbed on the Small Pore Scandium Terephthalate Metal Organic Framework, Sc2(O2CC6H4CO2)3

Langmuir ◽

10.1021/la803788u ◽

2009 ◽

Vol 25 (6) ◽

pp. 3618-3626 ◽

Cited By ~ 74

Author(s):

Stuart R. Miller ◽

Paul A. Wright ◽

Thomas Devic ◽

Christian Serre ◽

Gérard Férey ◽

...

Keyword(s):

Carbon Dioxide ◽

Single Crystal ◽

Metal Organic Framework ◽

X Ray Diffraction ◽

X Ray ◽

Small Pore ◽

Metal Organic ◽

Organic Framework

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Al1-x ScxN Thin Film Structures for Pyroelectric Sensing Applications

MRS Advances ◽

10.1557/adv.2016.510 ◽

2016 ◽

Vol 1 (39) ◽

pp. 2711-2716 ◽

Cited By ~ 2

Author(s):

V. Vasilyev ◽

J. Cetnar ◽

B. Claflin ◽

G. Grzybowski ◽

K. Leedy ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

Pyroelectric Coefficient ◽

X Ray Diffraction ◽

Ir Detectors ◽

Pyroelectric Properties ◽

X Ray ◽

Sensing Applications ◽

Pyroelectric Material ◽

Deposited Films

ABSTRACTAlN thin film structures have many useful and practical piezoelectric and pyroelectric properties. The potential enhancement of the AlN piezo- and pyroelectric constants allows it to compete with more commonly used materials. For example, combination of AlN with ScN leads to new structural, electronic, and mechanical characteristics, which have been reported to substantially enhance the piezoelectric coefficients in solid-solution AlN-ScN compounds, compared to a pure AlN-phase material.In our work, we demonstrate that an analogous alloying approach results in considerable enhancement of the pyroelectric properties of AlN - ScN composites. Thin films of ScN, AlN and Al1-x ScxN (x = 0 – 1.0) were deposited on silicon (004) substrates using dual reactive sputtering in Ar/N2 atmosphere from Sc and Al targets. The deposited films were studied and compared using x-ray diffraction, XPS, SEM, and pyroelectric characterization. An up to 25% enhancement was observed in the pyroelectric coefficient (Pc = 0.9 µC /m2K) for Sc1-xAlxN thin films structures in comparison to pure AlN thin films (Pc = 0.71 µC/m2K). The obtained results suggest that Al1-x ScxN films could be a promising novel pyroelectric material and might be suitable for use in uncooled IR detectors.

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Colossal Magnetoresistance in Thick La0.7Ca0.3MnO3 Films

MRS Proceedings ◽

10.1557/proc-384-427 ◽

1995 ◽

Vol 384 ◽

Cited By ~ 4

Author(s):

Randolph E. Treece ◽

P. Dorsey ◽

M. Rubinstein ◽

J. M. Byers ◽

J. S. Horwitz ◽

...

Keyword(s):

Colossal Magnetoresistance ◽

Single Phase ◽

Laser Deposition ◽

Orthorhombic Structure ◽

X Ray Diffraction ◽

Post Deposition Annealing ◽

X Ray ◽

Mr Effect ◽

Deposited Films ◽

Post Deposition

ABSTRACTThick films (0.6 and 2.0 μm) of the colossal magnetoresistance (CMR) material, La0.7Ca0.3MnO3 (LCMO), have been grown by pulsed laser deposition (PLD). The films were grown from single-phase LCMO targets in 100 mTorr 02 pressures and the material deposited on (100) LaAlO3 substrates at deposition temperatures of 800°C. The deposited films were characterized by X-ray diffraction (XRD), magnetic field-dependent resistivity, and Rutherford backscattering spectroscopy (RBS). The LCMO films were shown by XRD to adopt an orthorhombic structure. Brief post-deposition annealing led to ~50,000% and ~12,000% MR effect in the 0.6 μm and 2.0 μm films, respectively.

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