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微生物燃料电池非生物阴极催化剂的研究进展 总被引:1,自引:0,他引:1
在微生物燃料电池(MFC)中,以氧为电子受体具有很多优点,但氧阴极还原的反应动力学慢,会造成阴极电势的损失。 因此,提高阴极对氧还原的电催化活性和降低催化剂的价格是MFC非生物阴极催化剂的研究重点之一。 本文综述了近年来MFC中非生物阴极氧还原催化剂的研究进展。 重点讨论了贵金属Pt、过渡金属大环化合物以及金属氧化物催化剂对氧还原的电催化活性。 其中,非贵金属氧化物及过渡金属大环化合物催化剂具有良好的性能,而且价格低廉,有望成为MFC非生物阴极Pt基催化剂的替代催化剂。 相似文献
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通过电沉积的方法获得了一种具有均匀孔隙结构的海绵状二氧化锰催化剂,结合扫描电子显微镜(SEM)、X射线衍射(XRD)、X射线光电子能谱(XPS)等手段表征了所制备材料的表面形貌、结构及元素构成和赋存价态,采用线性伏安扫描(LSV)法对电沉积材料的电化学性能进行分析,考察其催化氧还原反应的活性,最后以合成的材料为阴极催化剂,构建微生物燃料电池系统,考察其在微生物燃料电池中的应用效果。结果表明,以电沉积二氧化锰为阴极催化剂的微生物燃料电池最大功率密度为975.6 mW/m~2,是以商业二氧化锰为阴极催化剂的电池的1.7倍;这表明作为一种经济、高效、环境友好的阴极氧还原催化剂,电沉积法制备的二氧化锰为实现阴极催化剂的低成本制备以及微生物燃料电池放大化推进提供了新的研究途径。 相似文献
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PEMFC氧电极的研究——助催化元素Ni和Co对Pt/C电催化剂性能的影响 总被引:1,自引:2,他引:1
通过液相共沉积技术在PEM燃料电池氧电极的Pt/C电催化剂中引入了Ni和Co两种助催化元素。经氧电极极化实验证明,这种新的电催化剂提高了氧的阴极还原的催化活性。当Ni和Co含量的质量分数分别为0.8%和1%时(以碳为基准),电催化活性较佳。SEM和TEM测试结果表明, Ni、Co助催化元素的引入有利于Pt在载体碳上的分散,减小了Pt的颗粒大小。经过96 h的恒流极化测试,电催化剂的活性没有明显的变化,显示稳定性良好。 相似文献
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将间接电合成苯甲醛与电还原马来酸制备丁二酸的过程有机结合, 构建了一个新的成对电解体系, 即在隔膜电解槽中, 以纯Pb为阴极, PbO2/Pb为阳极, 硫酸溶液为介质, 在施加超声波的条件下, 阳极氧化Ce3+为Ce4+, 阴极还原马来酸生成丁二酸; 同时, 在槽外采用Ce4+氧化甲苯生成苯甲醛. 实验结果表明, 阴极和阳极电解的平均电流效率分别为92.71%和87.81%, 总的电流效率高达180.52%; 且Ce4+槽外氧化甲苯为苯甲醛的收率为95.78%, 马来酸电还原为丁二酸的转化率为92.09%; 电解的槽电压与单一电解氧化Ce3+相比降低了0.25 V. 相似文献
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M. R. Tarasevich G. V. Zhutaeva M. V. Radina Z. R. Karichev E. A. Teishev J. H. Miners P. Goueres E. Sanchez-Corteron 《Russian Journal of Electrochemistry》2003,39(10):1094-1098
The activity of composite catalysts, Pt and Co-porphyrin- or Fe-phthalocyanine-based pyropolymers on low-disperse carbonaceous carriers (graphite, carbon black), in the oxygen and H2O2electroreduction in 1 M KOH is studied. Kinetic parameters of oxygen electroreduction are determined from experiments with rotating disk and model floating electrodes. Possible mechanism of the oxygen electroreduction reaction is discussed; it includes a slow stage of attachment of the second electron on the pyropolymer/carbonaceous carrier or joining the first electron (under the conditions of Temkin adsorption) on the platinum/graphite catalysts. 相似文献
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M. R. Tarasevich G. A. Kudaikulova K. A. Radyushkina 《Russian Journal of Electrochemistry》2000,36(1):49-53
The state of the surface of and the oxygen electroreduction on the naturally occurring minerals bornite, chalcopyrite, and
chalcosine are studied in borate buffer solutions using X-ray photoelectron spectroscopy, cyclic voltammetry, and the rotating
disk electrode technique. The surface of the minerals in an oxygen-containing atmosphere is covered with compounds of copper
and iron in the highest oxidation states, and the oxygen electroreduction occurs on these compounds. Electrocatalytic activity
of sulfide minerals during cathodic polarization is presumably due to the participation in the oxygen electroreduction reaction
of redox centers, i.e. ions of Fe(II) in bornite and chalcopyrite, and ions of Cu(I) bonded with the sulfide sulfur in each
of the minerals. 相似文献
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The mechanism of the electroreduction of oxygen on bare and Bi-submonolayer-modified Au(111) surfaces is examined using surface enhanced Raman scattering (SERS) measurements along with detailed density functional theory (DFT) calculations. The spectroscopy reveals the presence of superoxide-level species at potentials where oxygen is reduced. These species are not present in solutions absent either oxygen or Bi at these potentials. The spectroscopy also reveals the presence of Bi-OH species which are associated with peroxide reduction. Detailed calculations show oxygen associates much more strongly with Bi in the (2 x 2) configuration on Au(111) relative to the bare Au surface. Additionally, the O-O bond is elongated following O2 association, which follows as a consequence of Bi-O bond formation and partial oxidation of the Bi adatom. These results show for the first time that the four-electron electroreduction of oxygen electroreduction occurs via a series pathway on the Bi-modified surface in acid solution. 相似文献
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V. M. Andoralov M. R. Tarasevich O. V. Tripachev 《Russian Journal of Electrochemistry》2011,47(12):1327-1336
The mechanism of oxygen electroreduction on polycrystalline gold is studied in the acidic medium. Hydrogen peroxide is the
main reaction product. However, two potential regions can be singled out in which the oxygen electroreduction reaction proceeds
by different pathways. The first region is the potential interval close to the steady-state potential. Here, the oxygen electroreduction
virtually completely produces peroxide. The second interval is the potential range of considerable cathodic polarization values.
In this case, peroxide can be reduced to water. The low energy of hydrogen peroxide adsorption on gold determines the considerable
overpotential of peroxide reduction. It is shown that on the gold electrode surface, the catalytic decomposition of peroxide
occurs. The use of the method of electrochemical impedance spectroscopy allows the peculiarities of the oxygen reaction associated
with hydrogen peroxide transformations to be revealed. In the acidic medium, the reactions of consecutive reduction of oxygen
through the intermediate formation of hydrogen peroxide and the catalytic decomposition of the intermediate product are shown
to proceed simultaneously. The ratio of rate constants of electrochemical stages depends on the potential. The chemical decomposition
is observed both near the steady-state potential and in the cathodic region where considerable electrochemical reduction of
peroxide occurs. 相似文献
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V. V. Novikova S. P. Starodubova M. Yu. Chaika T. A. Kravchenko 《Russian Journal of Electrochemistry》2013,49(3):278-284
Silver particles are formed by electrochemical deposition on the carbon electrode surface. It is found that the deposition process occurs according to the progressive nucleation mechanism, which results in formation of silver particles with the size of 95 to 190 nm as dependent on the electrodeposition time. The values of silver particle size and support surface coverage by metal obtained on the basis of microphotographs indicate that cathodic polarization in the presence of dissolved oxygen results in particle size redistribution due to the reaction of silver particle dissolution with further deposition simultaneously with oxygen electroreduction. The reaction of molecular oxygen electroreduction on a carbon electrode with deposited dispersed silver occurs via a mixed two- and four-electron mechanism. The observed limiting reaction current is of diffusion nature. 相似文献
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The mechanism of the electroreduction of oxygen on Au surfaces in basic media is examined using surface-enhanced Raman scattering (SERS) measurements and density functional theory (DFT) calculations. The spectroscopy reveals superoxide species as a reduction intermediate throughout the oxygen electroreduction, while no peroxide is detected. The spectroscopy also shows the presence of superoxide after the addition of hydrogen peroxide. The calculations show no effect of OH addition to the Au(100) surface with regard to O-O length. These results suggest that the four-electron reduction of O(2) on Au(100) in base arises from a disproportionation mechanism which is enhanced on Au(100) relative to the other two low Miller index faces of Au. 相似文献
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S. Sepp E. Härk P. Valk K. Vaarmets J. Nerut R. Jäger E. Lust 《Journal of Solid State Electrochemistry》2014,18(5):1223-1229
Micro- and mesoporous carbide-derived carbons synthesized from molybdenum and tungsten carbides were used as porous supports for a platinum catalyst. Synthesized materials were compared with commercial Vulcan XC72R conducting furnace black. The scanning electron microscopy, X-ray diffraction, Raman spectroscopy, high-resolution transmission electron microscopy, and low-temperature N2 adsorption methods were applied to characterize the structure of catalysts prepared. The kinetics of oxygen electroreduction in 0.5 M H2SO4 solution was studied using cyclic voltammetry and rotating disk electrode methods. The synthesized carbide-derived carbons exhibited high specific surface area and narrow pore size distribution. The platinum catalyst was deposited onto the surface of a carbon support in the form of nanoparticles or agglomerates of nanoparticles. Comparison of carbide-derived carbons and Vulcan XC72R as a support showed that the catalysts prepared using carbide-derived carbons are more active towards oxygen electroreduction. It was shown that the structure of the carbon support has a great influence on the activity of the catalyst towards oxygen electroreduction. 相似文献
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T. A. Kravchenko L. N. Polyanskii V. A. Krysanov D. V. Konev M. Yu. Chayka 《Russian Journal of Electrochemistry》2006,42(11):1255-1261
The reduction of dissolved oxygen from a flowing aqueous solution of sodium sulfite on a cathodically polarized granulated layer of a copper-containing electron-ion exchanger is studied. It is established that the polarizing current is distributed over the layer height nonuniformly. A peak current corresponding to the oxygen electroreduction is discovered. The peak shifts from the inlet into the granulated layer to the exit out of it, which is connected with the advance of the concentration front and with an increase in ohmic resistance due to partial oxidation of copper centers. The distribution of the polarizing current is analogous to the distribution of the limiting current of the oxygen reduction, which is determined from polarization curves. The reaching of a stationary position of the peak of the polarizing current and the oxygen reduction degree with time testifies to the onset of a stationary state, at which the current turns limiting and the balance between the arrival and electroreduction of oxygen is fulfilled. 相似文献
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M. V. Novozhilova Yu. S. Danilova M. P. Karushev A. M. Timonov V. V. Malev O. V. Levin 《Russian Journal of Electrochemistry》2018,54(10):769-774
In energy-storage systems such as fuel cells and metal-air batteries, the main current-forming process is the reaction of oxygen electroreduction (OER). A simple method is proposed for synthesizing OER catalysts based on polymer complexes of transition metals (nickel, palladium) with Schiff bases prepared by electrochemical polymerization of starting monomers. The OER catalysts are prepared by thermolysis of polymers in inert atmosphere. Their properties are characterized by the methods of cyclic voltammetry with the use of a rotating disk electrode. The surface state (the catalyst film density, the size and composition of particles) is controlled by scanning electron microscopy with X-ray microanalysis. The electrode demonstrates the high catalytic activity in the oxygen electroreduction reaction in alkaline solutions (higher than 750 mA/mg of the initial polymer mass). 相似文献
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杂多阴离子在质子介质中的电还原行为已有大量报道“,“,已经证明杂多阴离子在还原后有质子化的过程发生,然而仅能从理论上推断质子化发生在桥氧上,尽管中子衍射可确定结晶中的质子位置,但是该方法太复杂,并且无法在溶液中进行现场研究.本文以现场FTIR光谱电化学方法对杂多阴离子PMO;刀X在质子介质中的电还原行为进行了研究,给出了杂多蓝质子化发生在桥氧上的新证据.考虑到红外光谱电化学方法中使用NaCI盐窗的要求和水溶液的强吸收等问题,我们选用经高氯酸酸化的乙脂溶液作为研究体系.1实验部分按文献[’1方法制备TBAsP… 相似文献