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61.
The bismuth film is a great promise as a suitable material to replace the mercury electrodes due to its low toxicity and good cathodic potential range. This work studies the influence of the electrodeposition conditions in the morphology and electroanalytical performance of the bismuth film electrodeposited onto copper electrode. The bismuth films were obtained in nitric or hydrochloric acid solutions with and without the presence of sodium citrate. The films were characterized by field emission scanning electron microscopy (FE‐SEM) and scanning electron microscopy with energy dispersive X‐ray spectrometry (SEM‐EDX). The microscopic analysis of the bismuth film obtained in HCl solution with sodium citrate (BIFE‐Cit) showed more homogeneous structure with higher content of bismuth than the film obtained in HCl only (BiFE‐HCl). The BiFE‐Cit exhibited a better analytical performance for lead with good adherence to the copper substrate. 相似文献
62.
Hydrogen peroxide biosensor based on electrodeposition of zinc oxide nanoflowers onto carbon nanotubes film electrode 总被引:2,自引:0,他引:2
Hui Ping Bai Xu Xiao Lu Guang Ming Yang Yun Hui Yang~* Department of Chemistry Chemical Engineering Yunnan Normal University Kunming China 《中国化学快报》2008,19(3):314-318
A new amperometric biosensor for hydrogen peroxide was developed based on adsorption of horseradish peroxidase at the glassy carbon electrode modified with zinc oxide nanoflowers produced by electrodeposition onto multi-walled carbon nanotubes (MWNTs) film. The morphology of the MWNTs/nano-ZnO electrode has been investigated by scanning electron microscopy (SEM), and the electrochemical performance of the electrode has also been studied by amperometric method. The resulting electrode offered an excellent detection for hydrogen peroxide at -0.11 V with a linear response range of 9.9×10^-7 to 2.9×10^-3 mol/L with a correlation coefficient of 0.991, and response time 〈5 s. The biosensor displays rapid response and expanded linear response range, and excellent stability. 相似文献
63.
离子液体AlCl3/Et3NHCl中电沉积法制备金属铝 总被引:6,自引:0,他引:6
在AlCl3/Et3NHCl型离子液体中铝电极上通过恒电位电解沉积制备出金属铝. 测定了不同摩尔比的AlCl3/Et3NHCl离子液体在不同温度下的电导率, 考察了离子液体AlCl3/Et3NHCl摩尔比为2/1中Al电极上铝沉积的晶核成核过程, 以及恒电位电解沉积铝的工艺条件对电流效率和沉积铝表面形貌的影响. 结果表明, 不同比例AlCl3/Et3NHCl离子液体的电导率随温度升高而升高, 符合Arrhenius规律; 在Al电极上铝沉积的成核机理为三维瞬时成核过程; 恒电位电解沉积结果表明, 室温下在电位-2.4 V(vs Pt)和电解时间20 min条件下, 沉积铝的表面形貌比较平整致密,电流效率达73%, 沉积铝的纯度达96%(w). 相似文献
64.
离子液体中钴的电沉积行为 总被引:3,自引:0,他引:3
在含有氯化钴的室温离子液体氯化1-甲基-3-乙基咪唑(EMIC)和乙二醇(EG)体系中研究了金属钴的电沉积. 循环伏安法测试表明, 在EMIC-CoCl2熔盐中, 乙二醇的加入促进了EMIC的解离, 从而使氧化还原电流增大, 在EMIC-CoCl2-EG体系中钴的电沉积是受扩散控制的非可逆电极过程, 在该电解液体系中, Co(II)在Pt电极上的传递系数α为0.30, 扩散系数D0为4.16×10-6 cm·s-1; 计时电流法研究表明, 钴在铂电极上的电结晶过程符合三维连续成核的生长机理; 场发射扫描电子显微镜(FE-SEM)观察镀层的微观形貌显示, 金属钴的结晶细小. XRD分析证实, 镀层为纯钴, 沉积的钴是晶态和微晶态的混合物, 并且晶粒尺寸为纳米级. 相似文献
65.
Superlattice nanowires are expected to show further enhanced thermoelectric performance compared with conventional nanowires or superlattice thin films. We report the epitaxial growth of high density Bi2Te3/Sb superlattice nanowire arrays with a very small bilayer thickness by pulse electrodeposition. Transmission electron microscopy, selected area electron diffraction and high resolution transmission electron microscopy were used to characterize the superlattice nanowires, and Harman technique was employed to measure the figure of merit (ZT) of the superlattice nanowire array in high vacuum condition. The superlattice nanowire arrays exhibit a ZT of 0.15 at 330 K, and a temperature difference of about 6.6 K can be realized across the nanowire arrays. 相似文献
66.
67.
悬浮粒子对电沉积Zn粉缓蚀性能的影响 总被引:1,自引:0,他引:1
在ZnCl2镀槽中悬浮一定量的不溶性粒子,如石墨PbC2,SnO2,TiO2,SiO2等,电沉积制备Zn粉,并对其结构,形貌及腐蚀行为进行分析,SEM的结果表明使用悬浮法可阻止Zn枝晶生长,悬浮PbO2,SnO2,TiO2,SiO2或In2O3等能明显地提高Zn粉在5mol/LKOH溶液中的缓蚀能力此外,文中还应用于分形理论对结果作了进一步讨论。 相似文献
68.
Metal/superconductor/semiconductor (Ag/Hg-1212/CdSe) hetero-nanostructures have been fabricated using pulse-electrodeposition
technique and are characterized by X-ray diffraction (XRD), full-width at half-maximum (FWHM) and scanning electron microscopy
(SEM) studies. The junction capacitance of Ag/Hg-1212, Hg-1212/CdSe and Ag/Hg-1212/CdSe heterojunctions is measured in dark
and under laser irradiation at room temperature. The nature of the junction formed and built-in-junction potentials were determined.
The increase in carrier concentration across the junction due to photo-irradiation has been observed. 相似文献
69.
H. Cesiulis A. Baltutiene M. Donten M. Donten Z. Stojek 《Journal of Solid State Electrochemistry》2002,6(4):237-244
Calculations based on the equilibria involved have been carried out to find the conditions of the highest possible solubility
of Ni(II) in an ammonia-citrate bath for the electrodeposition of amorphous/nanocrystalline Ni-W alloys. The appropriate increase
in the concentration of citrate, followed by the corresponding increase in the concentration of Ni(II), has led, under the
conditions of constant current, to the increase in the efficiency of the electrodeposition and therefore the rate of electrodeposition
by 3.2 times. The amorphous alloys obtained in solutions of different Ni(II) concentrations had different sizes of nanocrystals
(15–100 ?), as determined from X-ray diffractograms, and different alloy compositions (10–19.5 at% of W), but were of similar
high hardness.
Electronic Publication 相似文献
70.
One of the innovative technological directions for the high-temperature superconductors has been persued by fabricating the
heteroepitaxial multilayer structures such as superconductor-semiconductor heterostructures. In the present investigation,
metal/superconductor/semiconductor (Ag/Tl-2223/CdSe) hetero-nanostructures have successfully been fabricated using dc electrodeposition
technique and were characterized by X-ray diffraction (XRD), full-width at half-maximum (FWHM) and scanning electron microscopy
(SEM) studies. The measurement of junction capacitance as a function of biasing voltage was used for the estimation of junction
built-in-potential (V
D) and to study the charge distribution in a heterojunction. The Mott-Schottky plots were measured for each junction in dark
and under the photo-irradiation. The effect of laser irradiation on C-V characteristics of hetero-nanostructure has been studied. 相似文献