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1.
Proton conducting tantalum oxide films were deposited on ITO (Indium Tin Oxide) coated glass, fused silica and soda-lime glass
substrates by spin coating using a sol-gel process. The coating solutions were prepared using Ta(OC2H5)5 as a precursor. X-ray diffraction studies determined that the sol-gel films, heat treated at temperatures below 400°C, were
amorphous. Films heat treated at higher temperatures were crystalline with the hexagonal δ-Ta2O5 structure. The solar transmission values (T
s
) of tantala films on glass generally range from 0.8–0.9, depending on thickness. The refractive index and the extinction
coefficient were evaluated from transmittance characteristics in the UV-VIS-NIR regions. The refractive index values calculated
at λ=550 nm increased fromn=1.78 to 1.97 with increasing heat treatment from 150 to 450°C. The films heat treated at different temperatures showed low
absorption, with extinction coefficients of smaller thank=1×10−3 in the visible range. Impedance spectroscopic investigations performed on Ta2O5 films revealed that these films have a protonic conductivity of 3.2×10−4S/m. The films are suitable for proton conducting layers in electrochromic (EC) devices. 相似文献
2.
Regina M. Q. Mello José P. M. Serbena Adriano R. V. Benvenho Ivo A. Hümmelgen 《Journal of Solid State Electrochemistry》2003,7(8):463-467
We report the electrochemical preparation of poly(p-phenylene) (PPP) thin films with a polymerization degree of approximately 20 using biphenyl as starting material. The PPP
films are prepared directly on a tin oxide electrode, presenting a positive charge carrier mobility of 5×10−7 cm2 V−1 s−1. 相似文献
3.
Jun Zhang Xiu-li Wang Yuan Lu Ya Qiao Xin-hui Xia Jiang-ping Tu 《Journal of Solid State Electrochemistry》2011,15(10):2213-2219
Tungsten oxide (WO3) films were deposited on indium tin oxide glass by reactive DC magnetron sputtering of a tungsten target in an oxygen and
argon atmosphere at different substrate temperatures. Infrared reflectance modulation properties of the films were investigated
in the wavelength range of 2.5–25 μm. The morphology and structure of the films are strongly dependent on the substrate temperature,
and therefore have a great influence on infrared reflectance modulation properties. The charge capacity and diffusion coefficient
of H+ ions in WO3 films decrease, and the infrared reflectance modulation and color efficiency first increase and then decrease with increasing
the deposition temperature. The values achieve a maximum of 40% and 18.5 cm2 C−1, respectively, at 9 μm and 250 °C. 相似文献
4.
Eun-Seok Kang KyungHo Jung Deok Hai Park Namseok Kang Byunggil Ryu 《Journal of Sol-Gel Science and Technology》2012,62(3):333-337
The thermo-optic characteristics of the transparent glass fabric composite and matrix resin have been investigated. The inorganic–organic
hybrid materials modified with sulfur are synthesized as transparent matrix resin with the same refractive index and Abbe
number as glass. The optical characteristics of the transparent composite relate to temperature due to the fact that the thermo-optic
coefficient (dn/dT) for glass fiber (1.00 × 10−5K−1) is different to that of inorganic–organic hybrid materials (−1.99 × 10−4K−1). As the temperature increases, the transparent composite gradually becomes opaque and hazy due to the increased difference
in the refractive index between the glass fiber and the matrix. The change in optical characteristics is reversible, meaning
that the transparent composites can be used in for various applications in optical devices. 相似文献
5.
E. P. Surovoi N. V. Borisova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2009,83(13):2302-2307
The gravimetric and optical spectroscopic methods reveals that light irradiation with λ = 300–750 nm and intensity I = 6.9 × 1014–1.1 × 1016 quanta cm−2 s−1 for τ = 1–160 min in atmospheric conditions significantly changes the absorption and reflection spectra and mass of aluminum
films (d = 2–200 nm). The kinetic curves of the degree of conversion versus aluminum film thickness are satisfactorily described in
the inverse logarithmic and parabolic terms. The contact potential difference is measured for Al and Al2O3 films along with the photo-EMF of Al-Al2O3 systems. The suggested model includes the stages of generation and redistribution of nonequilibrium charge carriers in the
contact field of Al-Al2O3 systems, oxygen adsorption, Al3+ diffusion, and Al2O3 formation. 相似文献
6.
Franco Varsano Francesca Decker Enrico Masetti 《Monatshefte für Chemie / Chemical Monthly》2001,132(1):83-95
Summary. Ce-V mixed oxide films have been deposited by RF sputtering with the aim of increasing the Li charge capacity of counter
electrodes in smart windows. Such mixed oxides have shown high transmittance and optical passivity in the visible region.
After electrode pre-conditioning by cyclic voltammetry, a good electrochemical reversibility in LiClO4– propylene carbonate electrolyte was observed, and large Li-charge capacity under galvanostatic charging (up to 50 mCċcm−2) has been measured. The electrode charge capacity decreased after prolonged insertion-deinsertion cycles, whereas the photoptic
transmittance remained about constant. After 800 cycles the Li-charge capacity decreased to 40 mCċcm−2. The Li diffusion coefficient inside the films measured by electrochemical impedance and by galvanostatic titration ranged
from 10−11 cm2ċs−1 to 10−13cm2ċs−1. We observed that the Li charge capacity of the film electrodes is a function of the film deposition conditions, because
it increased with the vanadium oxide concentration in the target and with the oxygen content in the sputtering atmosphere.
Received June 23, 2000. Accepted (revised) August 7, 2000 相似文献
7.
Franco Varsano Francesca Decker Enrico Masetti 《Monatshefte für Chemie / Chemical Monthly》2001,15(2):83-95
Ce-V mixed oxide films have been deposited by RF sputtering with the aim of increasing the Li charge capacity of counter electrodes in smart windows. Such mixed oxides have shown high transmittance and optical passivity in the visible region. After electrode pre-conditioning by cyclic voltammetry, a good electrochemical reversibility in LiClO4– propylene carbonate electrolyte was observed, and large Li-charge capacity under galvanostatic charging (up to 50 mCċcm−2) has been measured. The electrode charge capacity decreased after prolonged insertion-deinsertion cycles, whereas the photoptic transmittance remained about constant. After 800 cycles the Li-charge capacity decreased to 40 mCċcm−2. The Li diffusion coefficient inside the films measured by electrochemical impedance and by galvanostatic titration ranged from 10−11 cm2ċs−1 to 10−13cm2ċs−1. We observed that the Li charge capacity of the film electrodes is a function of the film deposition conditions, because it increased with the vanadium oxide concentration in the target and with the oxygen content in the sputtering atmosphere. 相似文献
8.
Preparation and characterization of anion-cation surfactants modified montmorillonite 总被引:3,自引:2,他引:1
D. Chen J. X. Zhu P. Yuan S. J. Yang T. -H. Chen H. P. He 《Journal of Thermal Analysis and Calorimetry》2008,94(3):841-848
The low-temperature molar heat capacities of CoPc and CoTMPP were measured by temperature modulated differential scanning
calorimetry (TMDSC) over the temperature range from 223 to 413 K for the first time. No phase transition or thermal anomaly
was observed in the experimental temperature range for CoPc. However, a structural change was found to be nonreversible for
CoTMPP in the temperature range of 368–403 K, which was further validated by the results of IR and XRD. The molar enthalpy
ΔH
m and entropy ΔS
m of phase transition of the CoTMPP were determined to be 3.301 kJ mol−1 and 8.596 J K−1 mol−1, respectively. The thermodynamic parameters of CoPc and CoTMPP such as entropy and enthalpy relative to reference temperature
298.15 K were derived based on the above molar heat capacity data. Moreover, the thermal stability of these two compounds
was further investigated through TG measurements. Three steps of mass loss were observed in the TG curve for CoPc and five
steps for CoTMPP. 相似文献
9.
Letao Wang Yan Zhang Yongling Du Daban Lu Yuzhen Zhang Chunming Wang 《Journal of Solid State Electrochemistry》2012,16(4):1323-1331
Simultaneous determination of catechol (CC) and hydroquinone (HQ) were investigated by voltammetry based on glassy carbon
electrode (GCE) modified by poly (diallyldimethylammonium chloride) (PDDA) functionalized graphene (PDDA-G). The modified
electrode showed excellent sensitivity and selectivity properties for the two dihydroxybenzene isomers. In 0.1 mol/L phosphate
buffer solution (PBS, pH 7.0), the oxidation peak potential difference between CC and HQ was 108 mV, and the peaks on the
PDDA-G/GCE were three times as high as the ones on graphene-modified glass carbon electrode. Under optimized conditions, the
PDDA-G/GCE showed wide linear behaviors in the range of 1 × 10−6−4 × 10−4 mol/L for CC and 1 × 10−6−5 × 10−4 mol/L for HQ, with the detection limits 2.0 × 10−7 mol/L for CC and 2.5 × 10−7 mol/L for HQ (S/N = 3) in mixture, respectively. Some kinetic parameters, such as the electron transfer number (n), charge transfer coefficient (α), and the apparent heterogeneous electron transfer rate constant (k
s), were calculated. The proposed method was applied to simultaneous determine CC and HQ in real water samples of Yellow River
with satisfactory results. 相似文献
10.
Ronny Kleinhempel Gunar Kaune Matthias Herrmann Hartmut Kupfer Walter Hoyer Frank Richter 《Mikrochimica acta》2006,156(1-2):61-67
Indium tin oxide (ITO) thin films were deposited by mid frequency pulsed dual magnetron sputtering using a metallic alloy
target with 10 wt.% tin in an atmosphere of argon and oxygen. The aim of the work was to study the interdependence of structural,
electrical and optical properties of ITO films deposited in the reactive and transition target mode, respectively. The deposition
rate in the transition mode exceeds the deposition rate in the reactive mode by a factor of six, a maximum value of 100 nm·m min−1 could be achieved. This corresponds to a static deposition rate of 200 nm min−1. The lowest electrical resistivity of 1.1·10−3 Ω cm was measured at samples deposited in the high oxygen flow range in the transition mode. The samples show a good transparency
in the visible range corresponding to extinction coefficients being below 10−2. X-ray diffraction was used to characterise crystalline structure as well as film stress. ITO films prepared in the transition
mode show a slightly preferred orientation in (211) direction, whereas films deposited in the reactive mode are strongly (222)
oriented. Compared to undoped In2O3 all samples have an enlarged lattice. The lattice strain perpendicular to the surface is about 0.8% and 2.0% for films grown
in the transition and the reactive mode, respectively. Deposition in the transition mode introduces a biaxial film stress
in the range of −300 MPa, while stress in reactive mode samples is −1500 MPa. 相似文献
11.
A simple and sensitive self-ordered ring (SOR) technique, which was based on the capillary effect of solvent on a hydrophobic glass slide, was successfully applied to
the determination of gatifloxacin in milk, injection, human urine and rabbit serum samples. In a medium of pH 3.20 (HAc-NaAc)
with the aid of poly(vinyl alcohol)-124 (PVA-124), when 0.50 μL aluminum-sensitized gatifloxacin was dropped on glass slide
with dimethyl dichlorosilane (DMCS) pretreated, a typical fluorescent SOR with diameter (2R) of the ring less than ca. 1.77 mm and the belt width (2δ) less than 29.3 μm can be obtained. The solute on the ring belt
had strong fluorescence. Data of the imaged SOR showed that the gatifloxacin molecule across the SOR belt section follows
a Gaussian distribution. The assay showed that when the droplet volume is 0.1 μL, the SOR method could be used to determine
gatifloxacin in the range of 5.61 × 10−14 ∼ 1.50 × 10−12 mol/ring (5.61 × 10−8∼1.50 × 10−5 M) and the limit of determination (LOD) reached 5.61 × 10−15 mol/ring (5.61 × 10−8 M) with three-fold signal-to-noise ratio (S/N = 3). 相似文献
12.
Plasmas containing hexamethyldisilazane or hexamethylcyclotrisilazane and nitrogen or ammonia were used to deposit silicon
nitride-like films at low substrate temperature (T<60°C). Optical properties (refractive index and absorption coefficient), chemical composition of the deposit and film growth
rate were examined with respect to the deposition parameters (rf power, pressure and feed composition). As deposited films
from ammonia containing mixtures were silicon nitride-like, contained carbon, and were nearly oxygen free. Furthermore, only
Si−N, Si−H, and N−H bonds were identified in as-deposited films. The reactive Si−H bonds progressively transformed into Si−O
bonds as the films were exposed to air. Films deposited from highly ammonia-diluted mixtures, high RF power and low pressure
showed the highest stability with refractive indices as high as 1.8. 相似文献
13.
Electrical characterization of poly(3-methylthiophene) electrosynthesized onto a tin-oxide substrate
R. Valaski A. F. Bozza L. Micaroni I. A. Hümmelgen 《Journal of Solid State Electrochemistry》2000,4(7):390-393
We have investigated poly(3-methylthiophene) (PMeT) thin films electrochemically synthesized directly onto a tin-oxide (TO)
electrode. We find that the PMeT film thickness depends linearly on the charge density used during the electropolymerization.
We have demonstrated that the current transport in PMeT films (solid phase) is space-charge limited or controlled by thermionic
emission, depending on the electrode material. Using TO/PMeT/Ni devices we estimate the positive charge carrier mobility in
PMeT to be around 4 × 10−4 cm2 V−1 s−1, and the potential barrier height for positive charge carrier injection at the Al/PMeT interface to be 0.17 eV.
Received: 6 December 1999 / Accepted: 24 February 2000 相似文献
14.
This work reported for the first time the use of flow injection electrochemiluminescence (FI-ECL) sensor for the determination
of durabolin in an aqueous system based on CdTe quantum dot (QD) films. Aqueous CdTe colloidal solutions were prepared using
thioglycolic acid as a capping agent. Zetasizer Nano ZS (Malvern, UK) was employed to characterize the size of CdTe QDs. The
UV–vis and photoluminescence spectra of samples were systematically characterized. Indium tin oxide (ITO) slide glass was
modified with CdTe QDs by layer-by-layer self-assembly. CdTe QD films were packed into a homemade cell and used as a recognizer
of the FI-ECL sensor to determine durabolin. The intensive anodic ECL emission was obtained at a starting potential of +1.3 V
(vs. Ag/AgCl) in a carbonate bicarbonate buffer solution with a pH of 9.93 at an ITO electrode. The ECL intensity was correlated
linearly with the concentration of durabolin over the range of 1.0 × 10−8–1.0 × 10−5 g mL−1, and the detection limit was 2.5 × 10−9 g mL−1. The relative standard deviation for the determination of 1.0 × 10−6 g mL−1 durabolin was 1.04% (n = 11). This simple and sensitive sensor revealed good reproducibility for ECL analysis. As a result, the new FI-ECL sensor
had been successfully applied to the determination of durabolin in food samples. This strategy could be easily realized and
opened new avenues for the applications of QDs in ECL biosensing. 相似文献
15.
A sensitive complex absorptive wave of Ca-ARS was obtained by using differential pulse voltammetry when a mercury film glass
carbon electrode was immersed in 0.1 mol L−1 KOH and 4.5×10−4 mol L−1 ARS solution. The peak potential obtained was −1.17 V (vs Ag-AgCl). The peak current was proportional to the concentration
of calcium in the range of 5.0×10−8−4.2×10−5 mol L−1. The detection limit was 2.0×10−8 mol L−1. This method was applied successfully to determining traces of calcium in blood serum. The electrochemical behavior of the
system was also studied by cyclic voltammetry, and the experiment results showed that the electrode process was an irreversible
absorptive with two electrons participating.
Translated from Journal of Beijing Normal University (Natural Science Edition), 2005, 41(2) (in Chinese) 相似文献
16.
P. P. Levin P. V. Aboltin T. F. Shevchenko G. R. Kalamkarov 《High Energy Chemistry》2010,44(6):520-523
The kinetics of quenching of the all-trans-retinal triplet state by air oxygen in aqueous solutions of bovine serum albumin and in a cardiolipin liposome suspension
was investigated by nanosecond laser photolysis. It was established that the quenching reaction rate constant in the albumin
solution (1.8 × 108 l mol−1 s−1) was an order of magnitude less than in liposomes (3.1 × 109 l mol−1 s−1). These constants were 5.0 × 109 and 1.1 × 109 l mol−1 s−1 in methanol and aqueous solutions containing 10 vol % methanol, respectively. The effect of hindered oxygen access to the
Lall-trans-retinal attached to albumin is discussed in terms of its influence on the photooxidation processes in the retina. 相似文献
17.
Gongjun Yang Xilong Qu Ming Shen Chengyin Wang Qishu Qu Xiaoya Hu 《Mikrochimica acta》2008,160(1-2):275-281
Poly(phenol red) (denoted as PPR) films were electrochemically synthesized on the surface of a glassy carbon electrode (GCE)
by cyclic voltammetry to obtain a chemically modified electrode (denoted as PPR-GCE). The growth mechanism of PPR films was
studied by attenuated total reflection spectroscopy. This PPR-GCE was used to develop a novel and reliable method for the
determination of trace Pb2+ by anodic stripping differential pulse voltammetry. At optimum conditions, the anodic peak exhibits a good linear concentration
dependence in the range from 5.0 × 10−9 to 5.0 × 10−7 mol L−1 (r = 0.9989). The detection limit is 2.0 × 10−9 mol L−1 (S/N = 3). The method was employed to determine trace levels of Pb2+ in industrial waste water samples.
Correspondence: Gongjun Yang, Ming Shen, College of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002,
P.R. China 相似文献
18.
Tsung-Hsuan Tsai Tse-Wei Chen Shen-Ming Chen Ramiah Sarawathi 《Russian Journal of Electrochemistry》2012,48(3):291-301
The NiHCF-PEDOT, CuHCF-PEDOT and MnHCF-PEDOT films were prepared on glassy carbon electrode (GCE) by multiple scan cyclic
voltammetry and characterized using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and scanning electron
microscope (SEM) techniques. The advantages of these films are demonstrated for selectivity detection of ascorbic acid using
cyclic voltammetry and amperometric method. Interestingly, the NiHCF-PEDOT and CuHCF-PEDOT modified electrodes exhibited a
wide linear response range (5 × 10−6−3 × 10−4 M, R
2 = 0.9973 and 1.8 × 10−3−1.8 × 10−2 M, R
2 = 0.9924). The electrochemical sensors facilitated the oxidation of AA but not responded to other electroactive biomolecules
such as dopamine, uric acid, H2O2, glucose. The difference is MnHCF-PEDOT/GCE that no response to AA. In addition, the NiHCF-PEDOT and CuHCF-PEDOT modified
electrodes exhibited a distinct advantage of simple preparation, specificity, stability and reproducibility. 相似文献
19.
Krzysztof Miecznikowski James A. Cox Adam Lewera Pawel J. Kulesza 《Journal of Solid State Electrochemistry》2000,4(4):199-204
We describe a sol-gel approach by which iron hexacyanoferrate is immobilized in silica in a manner suited to investigation
by electrochemistry in the absence of a contacting liquid phase. Such physicochemical parameters as concentration of redox
sites (C
o) and apparent (effective) diffusion coefficient (D
app) are estimated by performing cyclic voltammetric and potential step experiments in two time regimes, which are characterized
by linear and spherical diffusional patterns, respectively. Values of D
app and C
o thereby obtained are 2.0 × 10−6 cm2 s−1 and 1.4 × 10−2 mol dm−3. The D
app value is larger than expected for a typical solid redox-conducting material. Analogous measurements done in iron(III) hexacyanoferrate(III)
solutions of comparable concentrations, 1.0 × 10−2 and 5.0 × 10−3 mol dm−3, yield D
app on the level of 5–6 × 10−6 cm2 s−1. Thus, the dynamics of charge propagation in this sol-gel material is almost as high as in the liquid phase. The residual
water in the silica, along with the pore structure, are important to the overall mechanism of charge transport, which apparently
is limited by physical diffusion rather than electron self-exchange. Under conditions of a solid state voltammetric experiment
which utilizes an ultramicroelectrode, encapsulated iron hexacyanoferrate redox centers seem to be in the dispersed colloidal
state rather than in a form of the rigid polymeric film.
Received: 8 April 1999 / Accepted: 13 August 1999 相似文献
20.
CuCrO2 and CuCrO2:Mn thin films were prepared on sapphire substrates by chemical solution deposition method. The effects of the annealing temperatures
and Mn concentration on the structural, electrical and optical properties were investigated. The X-ray diffraction measurement
was used to confirm the c-axis orientation of CuCrO2 and CuCrO2:Mn thin films. The maximum transmittances of the films in the visible region are about 65% with direct band gaps of 3.25 eV.
All films showed the p-type conduction and semiconductor behavior. The electrical conductivity decreases rapidly with the
increase of Mn content, the maximum of the electrical conductivity of 1.35 × 10−2 S cm−1 is CuCrO2 film deposited at 600 °C temperature in 10−3 Torr vacuum, which is about four orders of magnitude higher than that of the Mn-doped CuCrO2 thin film. The energy band of the samples is constructed based on the grain-boundary scattering in order to investigate the
conduction mechanism. Moreover, the samples exhibit a clear ferromagnetism, which was likely ascribed to originating from
the double-exchange interaction between the Mn3+ and Cr3+ ions. 相似文献