scholarly journals Characterization and Electrocatalytic Properties of Titanium-Based Ru0.3Co0.7−xCexMixed Oxide Electrodes for Oxygen Evolution in Alkaline Solution

2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
Hongjun Wu ◽  
Qin Ruan ◽  
Li Li ◽  
Baohui Wang
Keyword(s):  
Oxygen Evolution ◽  
Electrocatalytic Activity ◽  
Strong Dependence ◽  
Sol Gel ◽  
Active Surface ◽  
Catalytic Performance ◽  
Open Circuit ◽  
Active Surface Area ◽  
Oxide Electrodes ◽  
Sol Gel Process

Ti-supported RuO2-Co3O4-CeO2(Ru0.3Co0.7−xCexoxide,0≤x≤0.7) electrodes were prepared by sol-gel process. The phase structure, surface morphology, and microstructure of the oxide layer were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Electrocatalytic activity and oxygen evolution reaction (OER) kinetics on these electrodes in 1.0 mol⋅dm−3KOH solution were studied by recording open-circuit potential, cyclic voltammetry, and polarisation curves. The results showed that the appropriate content of CeO2could reduce the grain size and increase active surface area. The electrocatalytic activity shows a strong dependence on the CeO2content in the film. Catalytic performance of mixed oxide electrodes with 40 mol % CeO2was the best, with the greatest voltammetric charge, 86.23 mC⋅cm−2, and the smallest apparent activation energy for OER at 0.60 V was 22.76 kJ⋅mol−1.

scholarly journals The effect of the composition of the dispersing medium of oxide sols on the electrocatalytic activity of sol-gel obtained RuO2-TiO2/Ti anodes

2001 ◽  
Vol 66 (11-12) ◽  
pp. 847-857 ◽  
Author(s):  
Dejan Mitrovic ◽  
Vladimir Panic ◽  
Aleksandar Dekanski ◽  
Slobodan Milonjic ◽  
Radoslav Atanasoski ◽  
...  
Keyword(s):  
Surface Area ◽  
Electrocatalytic Activity ◽  
Sol Gel ◽  
Active Surface ◽  
Proton Exchange ◽  
Alcohol Molecule ◽  
Active Surface Area ◽  
Electrochemically Active ◽  
Dispersing Medium ◽  
Electrochemically Active Surface

The influence of the addition of methanol, ethanol, 1-propanol and 2-propanol to the dispersing medium of amixture of RuO2 and TiO2 sols on the electrochemically active surface area for proton exchange, as well as on the electrocatalytic activity for the chlorine evolution reaction (CER) of RuO2-TiO2/Ti electrode obtained by sol-gel procedure was investigated. The electrochemically active surface area was examined by cyclic voltammetry, while the analysis of the activity for the CER was performed by polarization measurements. The stability of the obtained anode coatings was also checked by an accelerated stability test. The anode properties depend on the number of C atoms in the alcohol molecule, as well as on the elapsed time between the preparation of the sols/alcohol mixture and its application onto the titanium support. The addition of alcohol increased the activity of the anodes for the CER, compared to those prepared without the addition, but their stability was smaller.

scholarly journals Preparation and Electrocatalytic Characteristics Research of Pd/C Catalyst for Direct Ethanol Fuel Cell

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Qiao Xia Li ◽  
Ming Shuang Liu ◽  
Qun Jie Xu ◽  
Hong Min Mao
Keyword(s):  
Fuel Cell ◽  
Average Particle Size ◽  
Active Surface ◽  
Carbon Support ◽  
Catalytic Performance ◽  
Active Surface Area ◽  
Average Particle ◽  
Ethanol Fuel ◽  
Direct Ethanol Fuel Cell ◽  
Electrochemical Active Surface Area

Two kinds of carbon-support 20% Pd/C catalysts for use in direct ethanol fuel cell (DEFC) have been prepared by an impregnation reduction method using NaBH4and NaH2PO2as reductants, respectively, in this study. The catalysts were characterized by XRD and TEM. The results show that the catalysts had been completely reduced, and the catalysts are spherical and homogeneously dispersed on carbon. The electrocatalytic activity of the catalysts was investigated by electrochemical measurements. The results indicate that the catalysts had an average particle size of 3.3 nm and showed the better catalytic performance, when NaBH4was used as the reducing agent. The electrochemical active surface area of Pd/C (NaBH4) was 56.4 m2·g−1. The electrochemical activity of the Pd/C (NaBH4) was much higher than that of Pd/C (NaH2PO2).

scholarly journals Study of the Oxygen Evolution Reaction at Strontium Palladium Perovskite Electrocatalyst in Acidic Medium

2020 ◽  
Vol 21 (11) ◽  
pp. 3785 ◽  
Author(s):  
Areej A. Eskandrani ◽  
Shimaa M. Ali ◽  
Hibah M. Al-Otaibi
Keyword(s):  
Oxygen Evolution ◽  
Oxygen Evolution Reaction ◽  
Electrocatalytic Activity ◽  
Electrochemical Impedance ◽  
Sol Gel ◽  
Combustion Method ◽  
Catalyst Stability ◽  
Hydroxyl Groups ◽  
Calculated Activation Energy ◽  
Calculated Activation

The catalytic activity of Sr2PdO3, prepared through the sol-gel citrate-combustion method for the oxygen evolution reaction (OER) in a 0.1 M HClO4 solution, was investigated. The electrocatalytic activity of Sr2PdO3 toward OER was assessed via the anodic potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The glassy carbon modified Sr2PdO3 (GC/Sr2PdO3) electrode exhibited a higher electrocatalytic activity, by about 50 times, in comparison to the unmodified electrode. The order of the reaction was close to unity, which indicates that the adsorption of the hydroxyl groups is a fast step. The calculated activation energy was 21.6 kJ.mol−1, which can be considered a low value in evaluation with those of the reported OER electrocatalysts. The Sr2PdO3 perovskite portrayed a high catalyst stability without any probability of catalyst poisoning. These results encourage the use of Sr2PdO3 as a candidate electrocatalyst for water splitting reactions.

Flowerlike submicrometer gold particles: Size- and surface roughness-controlled synthesis and electrochemical characterization

2010 ◽  
Vol 25 (9) ◽  
pp. 1755-1760 ◽  
Author(s):  
Changsheng Shan ◽  
Dongxue Han ◽  
Jiangfeng Song ◽  
Ari Ivaska ◽  
Li Niu
Keyword(s):  
Surface Area ◽  
Photoelectron Spectroscopy ◽  
Electrocatalytic Activity ◽  
Active Surface ◽  
Molar Ratio ◽  
Active Surface Area ◽  
Step Method ◽  
Gold Particles ◽  
X Ray ◽  
One Step

Flowerlike submicrometer gold particles were synthesized through a simple one-step method using p-diaminobenzene as a reductant in the presence of poly(sodium 4-styrenesulfonate) in aqueous solution. The particle size with diameters ranging from 267 to 725 nm could be tuned by varying the molar ratio of poly(sodium 4-styrenesulfonate) to HAuCl4, which also resulted in tunable roughness. The gold particles were confirmed by scanning electron microscopy, energy dispersive x-ray spectroscopy, x-ray diffraction, and x-ray photoelectron spectroscopy. Cyclic voltammetry showed that the specific surface area of the flowerlike particles was larger than that of sphere particles. The obtained flowerlike particles with higher surface area also exhibited higher electrocatalytic activity toward H2O2 and O2. The increase of electrocatalytic activity could be attributed to the increase of the active surface area.

scholarly journals Lanthanum-Based Perovskite-Type Oxides La1−xCexBO3(B = Mn and Co) as Catalysts: Synthesis and Characterization

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Nyamdavaa Erdenee ◽  
Uyanga Enkhnaran ◽  
Sevjidsuren Galsan ◽  
Altantsog Pagvajav
Keyword(s):  
Catalytic Activity ◽  
Sol Gel ◽  
Catalytic Performance ◽  
Reduction Behavior ◽  
Process Characterization ◽  
Lattice Geometry ◽  
Sol Gel Process ◽  
Ce Substitution ◽  
Crystallite Sizes ◽  
Perovskite Type

La1−xCexCoO3(x= 0, 0.2, 0.4) and La1−xCexMnO3(x= 0, 0.2) perovskite-type oxides were prepared by sol-gel process. Characterization techniques EDS, FTIR, XRD, BET, and XPS experiments were performed to survey the composition, bulk structure, and the surface properties of perovskites. The reduction behavior, thermal stability, and catalytic activity were studied by H2-TPR and catalytic performance. All synthesized samples showed well crystalline perovskite structure, 8–22 nm crystallite sizes, and SSA with 2–27 m2 g−1. The XRD results showed that the Ce substitution promoted the structural transformation for LaCoO3from rhombohedral into cubic and for LaMnO3no change in lattice geometry. Substitution with cerium (x= 0.2) showed smaller crystallite size, higher SSA, and the highest reducibility and catalytic activity for LaCoO3.

Synthesis of Cu–Ir nanocages with enhanced electrocatalytic activity for the oxygen evolution reaction

2015 ◽  
Vol 3 (39) ◽  
pp. 19669-19673 ◽  
Author(s):  
Chao Wang ◽  
Yongming Sui ◽  
Guanjun Xiao ◽  
Xinyi Yang ◽  
Yingjin Wei ◽  
...  
Keyword(s):  
Oxygen Evolution ◽  
Oxygen Evolution Reaction ◽  
Electrocatalytic Activity ◽  
Catalytic Performance ◽  
Single Crystalline

Single-crystalline Cu1.11Ir nanocages were synthesized, which exhibited high catalytic performance toward the oxygen evolution reaction in 0.05 M H2SO4.

scholarly journals Influence of Annealing Time of Aluminum AA1050 on the Quality of Cu and Co Nanocones

2020 ◽  
Vol 29 (12) ◽  
pp. 8025-8035
Author(s):  
Katarzyna Skibinska ◽  
Grzegorz Smola ◽  
Lukasz Bialo ◽  
Dawid Kutyla ◽  
Karolina Kolczyk-Siedlecka ◽  
...  
Keyword(s):  
Annealing Time ◽  
Bulk Material ◽  
Active Surface ◽  
Treatment Method ◽  
Open Circuit ◽  
Active Surface Area ◽  
Free Standing ◽  
Electrocatalytic Properties ◽  
1D Nanostructures

AbstractAnodization is a widespread surface treatment method for aluminum and its alloys; it also allows the formation of 1D nanostructures by a two-step process. Microstructure of the Al substrate and crystallographic texture after rolling and annealing have influence on the properties of AAO templates with conical nanopores. Synthesized free-standing 1D nanostructures ensure better electrocatalytic properties than bulk materials due to larger active surface area. In this work, the influence of annealing time at 500 °C on Vickers hardness and microstructure of aluminum AA1050 used in a two-step anodization process was investigated. The geometrical features of the templates such as interpore distance and number of pores per 1 μm2 were determined and compared. There is dependence between the time of the annealing process and surface quality of synthesized 1D Cu nanocone layers. The template, after 1 h of annealing, due to the largest active area and satisfactory quality of the nanocone surface, was chosen for synthesis of Co nanocones. The electrocatalytic properties of samples were measured in 1 M NaOH solution and compared with bulk material electrodeposited in the same conditions. The open circuit potential, connected with starting of hydrogen evolution reaction, was determined from the LSV curves. Active surface areas were determined for all samples using SEM photographs and taken into consideration during electrocatalytic tests. Possible behavior of hydrogen bubbles for the formation of nanostructures was considered.

Pd Nanoparticles Fabricated on Organic-Group Modified Silica and its Catalytic Performance for Acetylene Hydrogenation

2011 ◽  
Vol 233-235 ◽  
pp. 1884-1888
Author(s):  
Kang Jun Wang ◽  
Jing Wu ◽  
Ping Yu
Keyword(s):  
Sol Gel ◽  
Co Adsorption ◽  
Pd Nanoparticles ◽  
Catalytic Performance ◽  
Pd Catalyst ◽  
Modified Silica ◽  
In Situ Drifts ◽  
Organic Group ◽  
Sol Gel Process

Aminopropyl-functionalized silica (NH2-SiO2) was obtained via a sol-gel process using tetraethoxylsilicate (TEOS) and aminopropyltriethoxysilane (APTES). Aminopropyl group contained silica was further modified with formaldehyde to achieve a novel organic group modified silica, denoted as CH2O-SiO2. Using CH2O-SiO2 as support to prepare surported Pd catalyst (denoted as Pd/M-SiO2), small Pd nanoparticles (1-2 nm) were fabricated on CH2O-SiO2 surport. Hydrogenation of acetylene is used as probe reaction to evaluate the catalytic performance of Pd/M-SiO2. The results indicate that Pd/M-SiO2 exhibits unique catalytic property, which the selectivity of ethylene increases with the increase of acetylene conversion. In-situ DRIFTS spectra of CO adsorption show that the organic groups presented on the silica affect the electronic property of the very small Pd nanoparticles, which causes the change of reaction paths of hydrogenation of acetylene over Pd/M-SiO2 compared with traditional supported Pd catalyst.

Electrooxidation of Hydrogen on Nanostructured Pt/C Catalysts for Polymer Electrolyte Fuel Cells

2006 ◽  
Vol 518 ◽  
pp. 283-288
Author(s):  
B. Babić ◽  
Velimir Radmilović ◽  
N. Krstajić ◽  
B. Kaludjerović
Keyword(s):  
Surface Area ◽  
Hydrogen Oxidation ◽  
Sol Gel ◽  
Catalyst Support ◽  
Active Surface ◽  
Exchange Current ◽  
Active Surface Area ◽  
High Catalytic Activity ◽  
Hydrogen Oxidation Reaction ◽  
Order Of Magnitude

Mesoporous carbon cryogel synthesized by sol-gel polycondensation and freeze-drying with specific surface area (BET) of 517 m2 g-1 was used as a catalyst support. Pt/C catalysts were prepared by a modified ethylene glycol method (EG). Transmission electron microscopy (TEM) images show that the dispersion of the catalyst is very uniform with a mean particle size of about 2.65 nm. Hydrogen oxidation reaction (HOR) was studied on Pt/C catalyst in 0.5 mol dm-3 HClO4 acid solution. It has been found that HOR appears as a reversible two-electron direct discharged reaction (Tafel slope for this reaction is ≈30mV dec-1) and that Pt/C catalyst exhibits a very high catalytic activity. However, the corresponding value of the exchange current density obtained by dividing the exchange current by the active surface area of Pt particles has the same order of magnitude as those for the HOR in acidic solution at single crystal and polycrystalline Pt.

Sign in / Sign up

Export Citation Format

Share Document