排序方式: 共有22条查询结果,搜索用时 15 毫秒
1.
2.
The behavior of electrochemical cells Pt(sponge)/Na5TbSi412/Na0.65Co2(cell I) and Pt(sponge)/Na5TbSi412/Pt(sponge) (cell II) is studied by, respectively, potentiometric and impedance methods in oxygen and argon atmospheres at 50–300°C. Dependence of potential of cell I on the oxygen concentration is affected by the grain size of platinum sponge and the temperature. At 50–200°C the coarse-grained platinum electrode in contact with solid electrolyte Na5TbSi412 exhibits an oxygen function characterized by the potential-determining reaction 2(g) + 2 + 2 = –
2 + –. An impedance method shows the triple-phase boundary 2, Pt(sponge)/Na5TbSi412 to be reversible with respect to oxygen. The reversibility is realized by minority charge carriers in the solid electrolyte, i.e. by oxygen ions. 相似文献
3.
A. A. Bel’mesov A. V. Levchenko T. A. Palankoev L. S. Leonova A. E. Ukshe A. I. Chikin N. G. Bukun 《Russian Journal of Electrochemistry》2013,49(8):831-835
Electrocatalysts based on platinized titania modified with ruthenia (0–9 mol %) were studied. The synthesized materials were investigated as working electrodes in potentiometric sensors sensitive to hydrogen and carbon monoxide. All electrocatalysts showed reproducible behavior at pure gas concentrations from 400 to 4000 ppm. In CO-H2 mixtures with comparable concentrations of both gases, the sensors were selective toward hydrogen at ≥0.05 mol % Ru, but not selective to hydrogen or CO at less than 0.05 mol % Ru in the substrate. 相似文献
4.
The catalysts on carbon nanofibers with various platinum contents were synthesized. The morphology, resistance to oxidation,
and electrochemical behavior of the catalysts in the reactions that occur in fuel cells were studied. The dependence of the
specific output of cathodes of hydrogen—air fuel cells on the sizes of the platinum clusters was established. 相似文献
5.
6.
The behavior of sodium oxide bronzes in contact with sodium-conducting solid electrolytes in atmospheres of oxygen, carbon
dioxide, hydrogen sulfide, and humid air was investigated. The exchange currents at the NaxCoOy/NASICON interface was determined. It is shown that among the sodium-cobalt oxide bronzes the β-phase of the composition Na0.6CoO2 is the most reversible one (exchange current 236 μA/cm2).
Paper presented at the 1st Euroconference on Solid State Ionics, Zakynthos, Greece, 11–18 Sept. 1994 相似文献
7.
N. G. Bukun 《Ionics》1996,2(1):63-68
Four different methods, temperature dependent X-ray diffraction, impedance measurements, calorimetry and dilatometry, were
employed to investigate the superionic transitons of NASICON type materials. Two singularities are found at 160 – 170 °C and
about 230 °C. The first one is related to a second order phase transition close to the temperature of structural phase transition;
the second one coincides with the inflection in the temperature dependence of conductivity.
Paper presented at the 2nd Euroconference on Solid State Ionics, Funchal, Madeira, Portugal, Sept. 10–15, 1995 相似文献
8.
A. E. Ukshe L. V. Shmygleva A. V. Pisareva N. G. Bukun Yu. A. Dobrovol’skii 《Russian Journal of Electrochemistry》2013,49(8):807-812
Proton conductivity of special class of aromatic sulfonic acids is described, in particular, calixarene sulfonic acids that consist of flat anionic layers interlinked by labile two-dimensional hydrogen-bond network. High proton conductivity of their hydrates was observed earlier. The dependence of their transport characteristics (the proton conductivity, the activation energy of conductivity) was shown to have threshold character. The studied systems’ behavior is described on basis of percolation model that assumes changing of the proton transport mechanism at low water content in the structure. 相似文献
9.
L. A. Frolova Yu. A. Dobrovolsky N. G. Bukun 《Russian Journal of Electrochemistry》2011,47(6):697-708
Efficient oxide supported electrocatalysts for hydrogen and alcohol fuel cells are developed. They are characterized by a low content of platinum, exhibit high activity in the oxidation of low-molecular alcohols and tolerance to the CO poisoning. It is shown that the application of catalysts developed (Pt/SnO2-SbO x ) enables one to raise the power of fuel cells operating on ethanol approximately by two times as compared with similar fuel cells with commercial PtRu/C catalysts. 相似文献
10.
Impedance spectroscopy is employed for studying the behavior of the interface of the SmCo0.8Ti0.2O3 semiconducting oxide electrode with a sodium-conducting solid electrolyte (Na+–SE) in atmospheres of argon and oxygen. Compounds with the susceptibility to hydration decreasing in the row Na5TbSi4O12 Na3Zr2Si2PO12 Na3Sc2(PO4)3 are used as the Na+–SE. Only the systems containing the Na5TbSi4O12 solid electrolyte, the grain surfaces of which acquire boundary layers formed by hydration products, are sensitive to oxygen. The exchange current of the electrode reaction O2 (g) + e O2
– increases from 1.8 to 19 mA/cm2 in the temperature interval 250–300°C. The systems with Na+–SE that are not prone to hydration remain inactive in the oxygen atmosphere probably due to quick blocking of the active centers by nonconducting products of the secondary chemical reaction Na+ + O2
– NaO2. 相似文献