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排序方式: 共有1227条查询结果,搜索用时 15 毫秒
1.
N,N—双水杨醛乙二胺合钴—全氟磺酸膜修饰电极的电化学研究 总被引:10,自引:0,他引:10
实验发现中性分子N,N-双水杨醛乙二胺合钴(Co(salen)可以通过简单浸泡进入全氟磺酸(Nafion)膜,形成具有稳定电化学响应的Co(salen)-nafion修饰电极,X射线光电子能谱表明,Co(Salen)中心钴原子能与Nafion膜中磺酸根基团形成轴向配位,而使其由+2价变为+3价状态,电化学研究表明,Co(salen)在Nafion膜中的电荷转移是电活性物迁移和电子跳适共同控制的,同 相似文献
2.
We report the modification of various electrode surfaces with electropolymerized Magnus' green salts, [Pt(NH3)4 · PtCl4]
n
and [Pt(NH3)4 · PtCl6]
n
. The modified electrodes were prepared by cyclic scanning of the electrode potential in an aqueous solution containing Pt(NH3)4
2+ and PtCl4
2− or PtCl6
2− and the supporting electrolyte. The conditions for the film deposition were studied in detail. Several surface analytical
techniques, including micro-Raman scattering and X-ray diffraction, were employed to characterize the modifier film. The electrochemical
behavior of the modified electrode was studied in detail and the modified electrodes display very good electrocatalytic activity
in the oxidation of ascorbic acid, hydrogen peroxide, thiosulfate, and especially nitric oxide.
Received: 22 April 1999 / Accepted: 30 June 1999 相似文献
3.
Oxidation of a variety of compounds, including methionine (Met), using a complex formed between dirhodium(II) acetate and the lacunary form of phosphotungstic acid as the catalyst is effective over a wide range of conditions, including pH 2–10. Thus, amperometric detection at a composite in which this complex is immobilized in a sol–gel material does not place restrictions on selection of conditions for separations by reverse-phase HPLC. A demonstration of this point is shown by a study of Met, Met–Phe, Phe–Met, Met–Met, and Gly–Met–Gly (Phe, phenylalanine; Gly, glycine). Using a 0.05 M phosphate buffer at pH 6.7, a C18 column, and a flow rate of 1 ml min−1, capacity factors for Met, Gly–Met–Gly, Met–Met, and Phe–Met were 1.4, 2.1, 5.6, and 34, respectively. Phe–Met and Met–Phe co-eluted. 相似文献
4.
低电流密度下恒电流法制备的聚苯胺修饰电极 总被引:3,自引:1,他引:3
研究了低电流密度下恒电流法制备的聚苯(PA)修饰电极的性质及其影响因素,探讨了低电流密度聚合的PA膜的优点。发现此种条件下聚合的PA膜具有较好的电荷传输能力,它不仅对Br^-,Tl^+/Tl等电对的氧化还原反应有更好的电催化活性,而且对H^+的Nernast响应也更接近理论值。 相似文献
5.
催化电聚吡咯对苯二酚及邻苯二酚电催化反应的研究 总被引:6,自引:0,他引:6
本文通过循环伏安法研究了催化电聚吡咯膜(PPYE)对对苯二酚及邻苯二酚的电催化反应。讨论了酸度,膜厚度,扫速及浓度等条件对催化过程的影响,同时对二者的电催化反应过程进行了分析和比较。 相似文献
6.
硫酸介质中Ti/SnO2/PbO2析氧阳极的研究 总被引:13,自引:0,他引:13
由于硫酸溶液具有高的电导、一般条件下性质稳定、价格相对低廉等优点,所以电化学合成大多在硫酸溶液中进行.阳极析氧是电化学合成不可避免的阳极过程.但因硫酸的强腐蚀性,以及从阳极析出的氧的强氧化性,使得能满足工业生产的阳极材料很缺乏.自1950年荷兰Hen... 相似文献
7.
Electrocatalytic oxidation of hydrazine at cobalt hexacyanoferrate- modified glassy carbon, Pt and Au electrodes 总被引:1,自引:0,他引:1
The electrocatalytic oxidation of hydrazine has been studied on glassy carbon, Pt and Au electrodes modified by cobalt hexacyanoferrate
(CoHCF) using cyclic voltammetry and rotating disc techniques. It has been shown that the oxidation of hydrazine to nitrogen
occurs at the potential coinciding with that of Co(II) to Co(III) transformation in a CoHCF film, where no oxidation signal
is observed at a bare glassy carbon electrode. A Tafel plot, derived from RDE voltammograms, exhibits a slope of 150 mV, indicating
a one-electron charge transfer process to be the rate-limiting step. The electrocatalytic efficiency of the modified electrode
towards hydrazine oxidation depends on solution pH, and the optimum range was found to be located between pH 5 and pH 7. The
kinetic behaviour and location of the electrocatalytic process were examined using the W.J. Albery diagnosis table, and it
was concluded that the reaction has either a “surface” or a “layer” reaction mechanism. Pt- and Au-CoHCF-modified electrodes
show no significant electrocatalytic activity towards hydrazine oxidation.
Received: 25 April 1997 / Accepted: 12 August 1997 相似文献
8.
Rudolf Holze 《Journal of Solid State Electrochemistry》1998,2(2):73-77
The electrocatalysis of the Fe3+/2+ redox reaction at various electrode/electrolyte solution interfaces in the presence/absence of underpotential deposits of
various metals has been investigated by the AC impedance method. Exchange current densities and double layer capacity data
were obtained. On this basis, changes in the active surface area of the electrode and catalytic effects of the investigated
metals were identified.
Received: 27 May 1997 / Accepted: 29 July 1997 相似文献
9.
Lin Zhang Ivan Merino-Garcia Jonathan Albo Carlos M. Sánchez-Sánchez 《Current Opinion in Electrochemistry》2020
The electrochemical CO2 reduction reaction (CO2RR) either to generate multicarbon (C2+) or single carbon (C1) value-added products provides an effective and promising approach to mitigate the high CO2 concentration in the atmosphere and promote energy storage. However, cost-effectiveness of catalytic materials limits practical application of this technology in the short term. Herein, we summarize and discuss recent and advanced works on cost-effective oxide-derived copper catalysts for the generation of C2+ products (hydrocarbons and alcohols) and transition metal–nitrogen–doped carbon electrocatalytic materials for C1 compounds production from CO2RR. We think they represent suitable electrocatalyst candidates for scaling up electrochemical CO2 conversion. This short review may provide inspiration for the future design and development of innovative active, cost-effective, selective and stable electrocatalysts with improved properties for either the production of C2+ (alcohols, hydrocarbons) or carbon monoxide from CO2RR. 相似文献
10.
Dharmendra Kumar Yadav Devesh Kumar Singh Vellaichamy Ganesan 《Current Opinion in Electrochemistry》2020
To decrease the global carbon footprint concerns and to diminish the energy crisis, electrocatalytic reduction of CO2 which results in the formulation of value-added chemicals is a potential solution. In this review, single-atom catalysts (SACs) which are rapidly growing and being developed as the stimulating catalytic materials for electrocatalytic reduction of CO2 with improved selectivity, efficiency, and stability are considered. Various factors which are responsible for the efficient CO2 reduction are discussed. The pyrolytic approach for the preparation of Ni-based SACs and the maximum atom utilization efficiency for the desirable production of CO from CO2 are highlighted. 相似文献