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1.
A. A. Solov’ev N. S. Sochugov A. V. Shipilova K. B. Efimova A. E. Tumashevskaya 《Russian Journal of Electrochemistry》2011,47(4):494-502
Data on the mid-temperature solid-oxide fuel cells (SOFC) with thin-film ZrO2-Y2O3 (YSZ) electrolyte are shown. Such a fuel cell comprises a carrying Ni-YSZ anode, a YSZ electrolyte 3–5 μm thick formed by
vacuum ion-plasma methods, and a LaSrMnO3 cathode. It is shown that the use of a combined method of YSZ electrolyte deposition, which involves the magnetron deposition
of a 0.5–1.5-μm thick sublayer and its pulse electron-beam processing allows a dense nanostructured electrolyte film to be
formed and the SOFC working temperature to be lowered down as the result of a decrease in both the solid electrolyte Ohmic
resistance and the Faradaic resistance to charge transfer. SOFC are studied by the methods of voltammentry and impedance spectroscopy.
The maximum power density of the SOFC under study is 250 and 600 mW/cm−2 at temperatures of 650 and 800°C, respectively. 相似文献
2.
Xiong Yin Catherine Choong Liang Hong Zhaolin Liu 《Journal of Solid State Electrochemistry》2006,10(8):643-650
This work reports a new design of asymmetric tubular oxygen-permeable ceramic membrane (OPCM) consisting of a porous Y2O3 stabilized ZrO2 (YSZ) tube (with ∼1 μm of pore diameters and 31% porosity) as the support and a gas-tight mixed conductive membrane. The
membrane has an interlocking structure composed of a host matrix, Ag(Pd) alloy (9:1 by wt) doped perovskite-type (LSM80, 90wt%), and the embedded constituent, pristine LSM80. The Ag(Pd) alloy component promotes not only electronic conductivity
and mechanical strength but also reduction of both porosity and pore sizes in the layer (∼10-μm-thick) where it dopes. The
porous structure in this layer could then be closed through a solution coating procedure by which ingress of an aqueous solution
containing stoichiometric nitrate salts of La3+, Mn3+, and Sr2+ to the pore channels takes place first and the mixture of nitrate salts left after drying is subjected to pyrolysis to generate
tri-metal oxides in situ. This is followed by calcinations at l,300 °C to consolidate the embedded trioxide and to cohere
them with the Ag(Pd)-LSM80 host matrix. The structure formed is dubbed LSM80(S)-Ag(Pd)-LSM80, which was confirmed gas-tight
by electron micrograph and N2 permeation test. Finally, we assess the chemical compatibility between LSM80 and YSZ at the sintering temperature by X-ray
diffraction and electrochemical impedance analysis. The oxygen permeation of the fabricated LSM80(S)-Ag(Pd)-LSM80-YSZ membrane
is within the temperature range of 600 to 900 °C. The tests reveal good compatibility between the LSM80 and YSZ and a reasonably
high oxygen permeation flux in association with this OPCM assembly. 相似文献
3.
A. L. Stroyuk A. E. Raevskaya S. Ya. Kuchmii V. M. Dzhagan D. R. T. Zahn S. Schulze 《Theoretical and Experimental Chemistry》2007,43(1):28-34
A method was proposed for the production of colloidal nanoparticles of selenium stabilized by polymers and surfactants, and
their structural and optical characteristics were studied. It was shown that during the deposition of CdS and Cd0.5Zn0.5S on the surface of the Se nanoparticles followed by dissolution of the selenium with sodium sulfite it is possible to obtain
network “nanoframeworks” with size 30–50 nm, formed by CdS or Cd0.5Zn0.5S particles measuring 3–5 nm.
__________
Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 43, No. 1, pp. 24–29, January–February, 2007. 相似文献
4.
A. A. Kurteeva N. M. Bogdanovich D. I. Bronin N. M. Porotnikova G. K. Vdovin A. A. Pankratov S. M. Beresnev L. A. Kuz’mina 《Russian Journal of Electrochemistry》2010,46(7):811-819
The electrodes of solid-oxide fuel cells (SOFCs) must be characterized by high conductivity to decrease ohmic losses and sufficient
porosity to provide high gas diffusion rate. In the cases, when the SOFC electrodes are substrates, they must be synthesized
at the temperature above the temperature of formation of their solid-electrolyte coating. Herewith, manufacturing of supporting
electrodes with the required micro-structure is rather complicated. The present paper studies the effect of the method of
manufacturing of the initial La0.6Sr0.4MnO3 (LSM) powders, their degree of dispersion, introduction of sintering additives and pore agents on their microstructure, conductivity,
and possibility of adjusting the temperature of SOFC cathodic substrate formation at which the required characteristics are
reached. It is shown that sintering of cathodic substrates to the relative density of 65–70% can be carried out at the temperatures
from 1050 to 1350–1400°C, which would allow obtaining electrolyte films of powders with different sintering ability on such
substrates. The average pore size in cathodic substrates can be varied in the range of 0.4 to 2.5 μm by using the initial
LSM powder with different dispersion degree and by employing graphite as a pore agent. At 900°C, conductivity of cathodic
substrates of LSM grows at an increase in their relative density from 50% to 70% approximately from 50 to 100 S/cm and weakly
depends on the dispersion degree of the initial powders. 相似文献
5.
Large-scale Li1+x
V3O8 nanobelts were successfully fabricated using filter paper as deposition substrate through a simple surface sol–gel method.
The nanobelts were as long as tens of micrometers with widths of 0.4–1.0 μm and thickness of 50–100 nm. The nanobelts were
characterized by X-ray diffration (XRD), Fourier infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), transmission
electron microscopy (TEM). The formation mechanism of the nanobelts was investigated, showing that the morphology of the nanobelts
is mainly determined by the calcination temperature. Electrochemical properties of the Li1+x
V3O8 nanobelts were characterized by charge–discharge experiments, and the results demonstrate that the Li1+x
V3O8 nanobelts exhibit a high discharge capacity (278 mAh g−1) and excellent cycling stability. 相似文献
6.
Yeon-Tae Yu Jae-Chang Song Jeong-Hyun Kim Yoon-Su Kim Hong-Gi Lee 《Journal of Solid State Electrochemistry》2012,16(4):1377-1381
A Pt-loaded carbon black electrode was prepared by pulsed electrophoresis deposition in a Pt colloid solution as a plating
bath to overcome the growth problem of a Pt catalyst during deposition in an electrochemical process. This method is a promising
technique for preparing Pt catalyst layers at the polymer electrolyte/electrode interface. The particle size of the Pt catalyst
loaded by electrophoresis deposition was the same as that of Pt nanoparticles (3–4 nm) in a colloid and the particle size
was maintained even during deposition. The loading of the Pt catalyst was controlled by the pH of the Pt colloid and deposition
time. The Pt nanoparticles were deposited on a carbon black electrode to a depth of 2.5 μm. 相似文献
7.
K. P. Lopes L. S. Cavalcante A. Z. Simões R. F. Gonçalves M. T. Escote J. A. Varela E. Longo E. R. Leite 《Journal of Sol-Gel Science and Technology》2008,45(2):151-155
NiTiO3 (NTO) nanoparticles encapsulated with SiO2 were prepared by the sol–gel method resulting on core-shell structure. Changes on isoelectric point as a function of silica
were evaluated by means of zeta potential. The NTO nanoparticles heat treated at 600°C were characterized by X-ray diffraction,
transmission electron microscopy (TEM) and energy dispersive X-ray analysis. TEM observations showed that the mean size of
NTO is in the range of 2.5–42.5 nm while the thickness of SiO2 shell attained 1.5–3.5 nm approximately. 相似文献
8.
A. V. Spirin A. V. Nikonov A. S. Lipilin S. N. Paranin V. V. Ivanov V. R. Khrustov A. V. Valentsev V. I. Krutikov 《Russian Journal of Electrochemistry》2011,47(5):569-578
The paper presents the scientific basis and technical implementation of a method for obtaining oxygen by extraction from air
using an electrochemical cell based on a solid oxide cell (SOC) with anion-conducting solid electrolyte. A nanopowder of a
weak aggregate of the YSZ solid electrolyte and LSM fine powder was used to manufacture SOC. The electrolyte-electrode SOC
structure was formed as a tube by joint pressing of functional layers and the further co-sintering at the temperature of 1200°C.
The characteristics of an electrochemical cell of the oxygen pump based on a thin-wall tube of the YSZ supporting electrolyte
(150 μm) with symmetrical electrodes based on LSM (∼20 μm) are studied. A prototype of a compact oxygen generator (oxygen
pump) is developed and manufactured with an electrochemical part based on three serially connected SOCs. The connection is
implemented in the form of metallic couplings of the Crofer 22 APU steel. The method of reaction magnetron sputtering was
used to protect current leads from corrosion by applying a coating based on a Mn
x
Co3 − x
O4 spinel. The efficiency of a demonstration prototype at 800°C was 9 l/h at the power consumption of 50 W. The current density
through SOC was 1.1 A/cm2. The prototype was designed to contain no noble metal components. It is shown that the engineering approach applied allows
manufacturing effective nanostructural SOCs and devices on their basis. 相似文献
9.
Paper like free-standing hybrid single-walled carbon nanotubes air electrodes for zinc–air batteries
Nutan Gupta Tingji Toh Mak Wai Fatt Subodh Mhaisalkar Madhavi Srinivasan 《Journal of Solid State Electrochemistry》2012,16(4):1585-1593
Flexible electrode architectures based on non-functionalized (P2) and functionalized (P3) single-walled carbon nanotubes (SWNTs)
were fabricated via a simple vacuum filtration process. A hybrid layer of various compositions of P2- and P3-SWNTs forms free-standing
membranes (~80 μm in thickness), and their electrochemical performance was evaluated as an air electrode AEP2/P3 in zinc–air batteries. Such bifunctionalized air electrodes showed uniform surface morphology with interconnected micron-sized
porous structure with high porosity (~70%). The N2 adsorption isotherms at 77 K are of type IV with BET-specific surface areas of AE(60/40) and AE(80/20) to be 130.54 and 158.76 m2 g−1, respectively, thus facilitates high active surface area for active oxygen reduction/evolution reactions. BJH pore size distribution
of AE(60/40) and AE(80/20) shows maximum pores with diameter <15 nm. The zigzag interlaying of the SWNTs imparts mechanical stability and flexibility
in zinc–air batteries. Zinc–air batteries with optimized compositions of P2- and P3-SWNTs in air electrode AE(60/40) had ionic conductivity ~1 × 10−2 S cm−1 and delivered higher discharge capacity ~300 mAh g−1 as compared to AE(80/20) composition. The unique properties of AE(P2/P3) studied in this work would enable flexible air electrode architectures in future metal–air batteries. 相似文献
10.
Shilin Liu Dingning Ke Jian Zeng Jinping Zhou Tianyou Peng Lina Zhang 《Cellulose (London, England)》2011,18(4):945-956
In our previous work, the CdS nanoparticles/cellulose films exhibited significantly high photocatalytic H2 production efficiency under visible light irradiation than the ordinary CdS photocatalyst. In present paper, the CdS nanoparticles
were synthesized in situ in pores of the regenerated cellulose substrate and the porous structure of cellulose, formation
of the CdS nanoparticles and interactions between CdS and cellulose matrix in the composite films were investigated deeply.
The experimental results indicated that the micro-nano-porous structure of the cellulose matrix could be used easily to create
inorganic nanoparticles, which supplied not only cavities for the formation of nanoparticles, but also a shell (semi-stiff
cellulose molecules support the pore wall) to protect their nano-structure. When the cellulose films with porous structure
at wet state were immersed into inorganic ions solution, the ions interacted immediately with the –OH groups of cellulose,
and then transformed into inorganic composite via another treatment, finally inorganic nanoparticles formed during the dry.
The pore size of the cellulose matrix decreased from 180 nm (at wet state) to about 18 nm (at dry state), leading to the formation
of nanoparticles. The results revealed that the CdS nanoparticles with a mean particle diameter about 6 nm were dispersed
well, and were immobilized tightly in the cellulose matrix, resulting in a portable photocatalyst with high efficiency for
photocatalytic for H2 evolution. This is simple and “green” pathway to prepare the organic–inorganic hybrid materials. 相似文献
11.
Farook Adam Thiam-Seng Chew Jeyashelly Andas 《Journal of Sol-Gel Science and Technology》2011,59(3):580-583
Mesoporous silica nanoparticles with a spherical morphology have been synthesized from rice husk (agricultural biomass) by
a simple, template-free synthetic approach, which was carried out via sol–gel technique at ambient condition. Transmission
electron micrographs revealed the formation of spherical silica nanoparticles with an average diameter of 50.9 nm. From the
nitrogen adsorption–desorption analysis, the rice husk silica shows a high specific BET surface area of 245 m2 g−1. The silica nanoparticles have a narrow pore size distribution of 5.6–9.6 nm. 相似文献
12.
Salwa Meredith Hashim Abdul Rahman Mohamed Subhash Bhatia 《Journal of Sol-Gel Science and Technology》2011,59(3):505-512
Perovskite-type La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF6428) thin-film membrane prepared by modified Pechini sol–gel process, was successfully deposited on porous support
of similar composition using dip-coating method. Fine grain and crack-free film with perovskite structure was obtained at
sintering temperature of 800 °C and dwelling time of 60 min. The cross-sectional image indicated that LSCF6428 thin-film membrane
coated on the porous support showed excellent adhesion to the support with uniform thickness. The minimum dense layer thickness
obtained by dip-coating method was around 0.5 μm. It was found that the oxygen permeability of the supported thin film was
lower than that of the perovskite support, which indicated that the pores of the support were reduced by thin-film deposition
on the support surface. The reduction in the pore size led to the more selective permeation mechanism contributes to the overall
permeation. Successful deposition of LSCF6428 thin-film membrane on porous support can be considered as a promising technique
for the preparation of oxygen separation membrane. 相似文献
13.
Li Chen Haixia Shen Zhen Lu Cang Feng Su Chen Yanru Wang 《Colloid and polymer science》2007,285(13):1515-1520
TiO2–SiO2 composite nanoparticles were prepared by a sol–gel process. To obtain the assembly of TiO2–SiO2 composite nanoparticles, different molar ratios of Ti/Si were investigated. Polyurethane (PU)/(TiO2–SiO2) hybrid films were synthesized using the “grafting from” technique by incorporation of modified TiO2–SiO2 composite nanoparticles building blocks into PU matrix. Firstly, 3-aminopropyltriethysilane was employed to encapsulate TiO2–SiO2 composite nanoparticles’ surface. Secondly, the PU shell was tethered to the TiO2–SiO2 core surface via surface functionalized reaction. The particle size of TiO2–SiO2 composite sol was performed on dynamic light scattering, and the microstructure was characterized by X-ray diffraction and
Fourier transform infrared. Thermogravimetric analysis and transmission electron microscopy (TEM) employed to study the hybrid
films. The average particle size of the TiO2–SiO2 composite particles is about 38 nm when the molar ratio of Ti/Si reaches to1:1. The TEM image indicates that TiO2–SiO2 composite nanoparticles are well dispersed in the PU matrix. 相似文献
14.
The size effect of silica nanoparticles (SiO2) on thermal decomposition of poly(methylmethacrylate) (PMMA) was investigated by the controlled rate thermogravimetry. Thermal
degradation temperature of PMMA–SiO2 composites depended on both fraction and size of SiO2, the thermal degradation temperature of 23 nm (diameter) SiO2–PMMA (6.1 wt%) was 13.5 °C higher than that of PMMA. The thermal stabilities of 17 nm SiO2–PMMA (3.2 wt%) and 13 nm SiO2–PMMA (4.8 wt%) were 21 and 23 °C, respectively, higher than that of PMMA without SiO2. The degree of degradation improvement was increased linearly with the surface area of SiO2. The number of surface hydroxyl group in unit volume of SiO2 particle increased with increasing the specific surface area of SiO2, and the interaction between hydroxide group of SiO2 and carbonyl group of PMMA had an important role to improve the thermal stability of PMMA. 相似文献
15.
Murugan Veerapandian Suk Kyung Lim Hyang Mi Nam Gobianand Kuppannan Kyusik S. Yun 《Analytical and bioanalytical chemistry》2010,398(2):867-876
We report the analytical and in vitro antibacterial activity of glucosamine-functionalized silver glyconanoparticles. Morphological
characterization ensured the surface topography and particle size distribution of both silver and glucosamine–silver nanoparticles.
Surface plasmon resonance of both types of nanoparticle was determined from UV–visible spectroscopy using four different sample
concentrations (10–40 μL). The resulting functionalized glyconanoparticles show maximum absorbance with a red shift of 30 ± 5 nm
(390–400 nm) from their initial absorbance (425–430 nm). FT-Raman and 1H-NMR spectroscopic measurement confirmed the surface functionalization of glucosamine on the silver surface through the carbonyl
group of a secondary amide linkage (–NH–CO–), elucidated by the conjugation of N-hydroxysuccinimide (NHS)-terminated silver nanoparticles and the amino group of glucosamine. Antimicrobial experiments with
well-characterized silver nanoparticles (AgNPs) and glucosamine-functionalized silver nanoparticles (GlcN-AgNPs) demonstrate
that GlcN-AgNPs have similar and enhanced minimum inhibitory concentration (MIC) against eight gram-negative and eight gram-positive
bacteria compared with AgNPs. MIC data shows that Klebsiella pneumoniae (ATCC 700603) and Bacillus cereus isolate express high levels of inhibition, with the quantity and magnitude of inhibition being higher in the presence of
GlcN-AgNPs. 相似文献
16.
K. E. Collins M. L. M. M. Granja R. G. Pereira Filho T. A. Anazawa I. C. S. F. Jardim 《Chromatographia》1997,45(1):99-103
Summary Poly(methyloctylsiloxane) (PMOS), sorbed into the pores of HPLC silica particles by solvent evaporation, can function as a
useful stationary phase for reversed-phase chromatography. The present work addresses the question of how the PMOS is distributed
in the pores. Measurements of the surface area (BET, N2) of a series of partially loaded samples (0–40% PMOS, m/m) using a typical batch of HPLC silica (10 μm irregular particles
with 6 nm pores) show that the specific surface area of the samples decreases linearly with the specific loading (mass of
PMOS per gram of silica). This result is not consistent with a “film” model in which the PMOS is deposited uniformly on the
pore walls, but is consistent with a model in which long segmented “plugs” of PMOS are deposited within the pore system.
Presented at the 21st ISC held in Stuttgart, Germany, 15th–20th September, 1996 相似文献
17.
RuO2 nanostructures were synthesized by heating Ru nanoparticles in air at 280°C using Cu as catalyst. The Ru nanoparticles were
prepared by the pyrolysis of ruthenium precursors in a vacuum using multi-walled carbon nanotubes as templates. The RuO2 nanostructures grew radically with diameters of 50–150 nm, and lengths of 0.5–2.0 μm. The growth of nanostructure mainly
depends on the dispersivity of Ru nanoparticles on MWNTs. The electrochemical property of these nanostructures was studied
by cyclic voltammetry.
Electronic Supplementary Material Supplementary material for this article is available at and is accessible for authorized users. 相似文献
18.
Y. J. Leng S. H. Chan K. A. Khor S. P. Jiang 《Journal of Solid State Electrochemistry》2006,10(6):339-347
Development of high performance cathodes with low polarization resistance is critical to the success of solid oxide fuel cell
(SOFC) development and commercialization. In this paper, (La0.8Sr0.2)0.9MnO3 (LSM)–Gd0.2Ce0.8O1.9(GDC) composite powder (LSM ~70 wt%, GDC ~30 wt%) was prepared through modification of LSM powder by Gd0.2Ce0.8(NO3)
x
solution impregnation, followed by calcination. The electrode polarization resistance of the LSM–GDC cathode prepared from
the composite powder was ~0.60 Ω cm2 at 750 °C, which is ~13 times lower than that of pure LSM cathode (~8.19 Ω cm2 at 750 °C) on YSZ electrolyte substrates. The electrode polarization resistance of the LSM–GDC composite cathode at 700 °C
under 500 mA/cm2 was ~0.42 Ω cm2, which is close to that of pure LSM cathode at 850 °C. Gd0.2Ce0.8(NO3)
x
solution impregnation modification not only inhibits the growth of LSM grains during sintering but also increases the triple-phase-boundary
(TPB) area through introducing ionic conducting phase (Gd,Ce)O2-δ, leading to the significant reduction of electrode polarization resistance of LSM cathode. 相似文献
19.
Ting Li Brian Albee Matti Alemayehu Rocio Diaz Leigha Ingham Shawn Kamal Maritza Rodriguez Sandra Whaley Bishnoi 《Analytical and bioanalytical chemistry》2010,398(2):689-700
A comparative assessment of the 48-h acute toxicity of aqueous nanoparticles synthesized using the same methodology, including
Au, Ag, and Ag–Au bimetallic nanoparticles, was conducted to determine their ecological effect in freshwater environments
through the use of Daphnia magna, using their mortality as a toxicological endpoint. D. magna are one of the standard organisms used for ecotoxicity studies due to their sensitivity to chemical toxicants. Particle suspensions
used in toxicity testing were well-characterized through a combination of absorbance measurements, atomic force or electron
microscopy, flame atomic absorption spectrometry, and dynamic light scattering to determine composition, aggregation state,
and particle size. The toxicity of all nanoparticles tested was found to be dose and composition dependent. The concentration
of Au nanoparticles that killed 50% of the test organisms (LC50) ranged from 65–75 mg/L. In addition, three different sized Ag nanoparticles (diameters = 36, 52, and 66 nm) were studied
to analyze the toxicological effects of particle size on D. magna; however, it was found that toxicity was not a function of size and ranged from 3–4 μg/L for all three sets of Ag nanoparticles
tested. This was possibly due to the large degree of aggregation when these nanoparticles were suspended in standard synthetic
freshwater. Moreover, the LC50 values for Ag–Au bimetallic nanoparticles were found to be between that of Ag and Au but much closer to that of Ag. The bimetallic
particles containing 80% Ag and 20% Au were found to have a significantly lower toxicity to Daphnia (LC50 of 15 μg/L) compared to Ag nanoparticles, while the toxicity of the nanoparticles containing 20% Ag and 80% Au was greater
than expected at 12 μg/L. The comparison results confirm that Ag nanoparticles were much more toxic than Au nanoparticles,
and that the introduction of gold into silver nanoparticles may lower their environmental impact by lowering the amount of
Ag which is bioavailable. 相似文献
20.
M. Jafarzadeh I. A. Rahman C. S. Sipaut 《Journal of Sol-Gel Science and Technology》2009,50(3):328-336
A modified preparation of silica nanoparticles via sol–gel process was described. The ability to control the particle size
and distribution was found highly dependent on mixing modes of the reactants and drying techniques. The mixture of tetraethoxysilane
and ethanol followed by addition of water (Mode-A) produced monodispersed powder with an average particle size of 10.6 ± 1.40 nm
with a narrow size distribution. The freeze drying technique (FD) further improved the quality of powder. In addition, the
freeze dried samples have shown unique TGA decomposition steps which might be related to the well-defined structure of silica
nanoparticles as compared to the heat dried samples. DSC analysis showed that FD preserved the silica surface with low shrinkage
and generated remarkably well-order, narrow and bigger pore size and pore volume and also large endothermic enthalpies (ΔH
FD = −688 J g−1 vs. ΔH
HD = −617 J g−1) that lead to easy escape of physically adsorbed water from the pore at lower temperature. 相似文献