共查询到20条相似文献,搜索用时 15 毫秒
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Polypyrrole microstructures with unusual morphologies have been synthesized by direct electrochemical oxidation of pyrrole in beta-naphthalenesulfonic acid aqueous solution. 相似文献
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Angkoonna Pringkasemchai Faegheh Hoshyargar Benchaporn Lertanantawong Anthony P. O'Mullane 《Electroanalysis》2019,31(11):2095-2102
Gold nanostructures were fabricated on a transparent indium tin oxide (ITO) coated PET substrate by an electrodeposition technique from a potassium gold (III) chloride solution for two different types of applications. It was found that the optical transparency of lightweight ITO electrodes could be maintained by depositing isolated gold nanostructures while opening up the use of these electrodes for inner sphere electron reactions, such as hydroquinone oxidation, which are not possible at ITO electrodes. For practical applications the adhesion of gold to the ITO electrode was improved by modifying the ITO surface with 3‐mercaptopropyl‐trimethoxysilane (MPS). Compared to Au/ITO, the Au/MPS/ITO electrode showed vastly improved electrochemical activity toward various electron transfer reactions when subjected to mechanical stress. The biosensing properties of the Au/MPS/ITO electrode was also investigated by studying the detection of immobilized DNA on the Au/MPS/ITO electrode via electrochemical impedance spectroscopy (EIS). 相似文献
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紫外光照下纳米TiO2电极的电化学行为 总被引:9,自引:0,他引:9
通过电沉积方法制备了纳米TiO2薄膜电极,应用循环伏安和交流阻抗技术研究了TiO2电极在253.7 nm的紫外光照射下的电化学行为.结果表明, TiO2薄膜电极的循环伏安图在+0.15 V处出现新的氧化峰,交流阻抗谱的半圆明显减小,电极的开路电位在有光和无光的情况下呈现规律变化.实验证实在紫外光照射下电极表面有新物种Ti3+生成,但光生Ti3+不稳定. 相似文献
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Hong D Kang K Hong SP Shon HK Son JG Lee TG Choi IS 《Langmuir : the ACS journal of surfaces and colloids》2012,28(1):17-21
In this paper, carbamate-based self-assembled monolayers (SAMs) of alkanethiolates on gold were suggested as a versatile platform for release of amine-bearing molecules in response to the electrical signal. The designed SAMs underwent the electrochemical oxidation on the gold surface with simultaneous release of the amine molecules. The synthesis of the thiol compounds was achieved by coupling isocyanate-containing compounds with hydroquinone. The electroactive thiol was mixed with 11-mercaptoundecanol [HS(CH(2))(11)OH] to form a mixed monolayer, and cyclic votammetry was used for the characterization of the release behaviors. The mixed SAMs showed a first oxidation peak at +540 mV (versus Ag/AgCl reference electrode), indicating the irreversible conversion from carbamate to hydroquinone groups with simultaneous release of the amine molecules. The analysis of ToF-SIMS further indicated that the electrochemical reaction on the gold surface successfully released amine molecules. 相似文献
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Silicone elastomers are used as dielectric electroactive polymers for making actuators, generators, sensors, and as artificial muscles in medical applications. Current requirements in the actuator manufacturing put a strict limitation on the thickness of the elastomers, such that a maximum permissible thickness is around 25–50 µm. The relatively small Young's modulus for these elastomers is a requirement for actuation capabilities. However, peeling and release of such films during manufacture processes are very difficult. To ease the release of the films, techniques such as the use of release agents like surfactants and detergents, incorporating resins in the silicone matrix and grafting/adding low surface energy functionalities to the silicone elastomer have been tested. The methods used are required not to interfere with the Young's modulus and the dielectric permittivity in a negative way. Polysorbate‐20, a non‐ionic surfactant, fulfills all requirements and gives the lowest peel forces for the films. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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Electrochemical activity and morphology of human erythrocytes at optically transparent ITO electrode
A. Yu. Tsivadze M. Sh. Khubutiya A. K. Evseev I. V. Goroncharovskaya N. V. Borovkova A. I. Shapiro O. V. Batishchev M. M. Goldin 《Doklady Physical Chemistry》2017,477(1):201-204
The electrochemical activity of a suspension of human erythrocytes was found at potentials above +0.4 V. The limiting current of electrooxidation was found to linearly depend on the cell concentration in the suspension. The electrochemical activity of an erythrocyte suspension is accompanied by reversible changes in the cell morphology only in non-buffered media. 相似文献
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电化学控制释放三磷酸腺苷 总被引:3,自引:0,他引:3
在含有甲苯磺酸钠和吡咯的水溶液中电化学合成聚吡咯膜.当膜在三磷酸腺苷(ATP)的溶液中氧化时,ATP掺入膜内;当膜还原时ATP从膜中释放出来, 释放出的ATP的量可由紫外可见光谱法测定. 相似文献
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Recently, low temperature synthesis of ITO thin film of low resistivity is desired in the field of LCD (Liquid Crystalline
Display) production. This paper describes the results of experiment to produce ITO thin film from a sol containing crystalline
ITO particles and alkoxides of In and Sn. Crystallization temperature of ITO thin film obtained from the sol mixed with ITO
powder was lower than that of ITO from the sol without ITO powder. Furthermore, the resistivity of the former ITO thin film
was lower than that of the latter. It was assumed that these results were attributed to the promotion effect of ITO crystalline
particles to crystalize the amorphous ITO gel at lower temperature. This low temperature crystallization effect plays an important
role in enhancing the crystallinity and electric conductivity of ITO thin film from sol-gel process. 相似文献
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We have shown hollow Ni nanonodules with outer diameters of 80-200 nm and wall thicknesses of 5-25 nm could be prepared by electrochemical deposition in the NiCl2 + dimethyl sulfoxide + C2H4O3 + H2O system, and the products were high purity. In particular, Ni hollow nanonodule structures or highly assembling Ni hollow nanostructures can be selected by varying the compositions of the solvent mixture. Apart from the hollow grain size, the wall thickness can also easily be controlled by varying the electrochemical parameters, salt concentration, and deposition time. The typical coercivity of Ni hollow nanostructures with particle sizes of about 100-150 nm was much bigger than that of the bulk Ni. 相似文献
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Xiao Feng QIU Jin Zhong XU Jun Jie ZHU* Hong Yuan CHEN Department of Chemistry State key Laboratory of Coronation Chemistry Nanjing University Nanjing 《中国化学快报》2002,13(7):649-652
ITO is a versatile material in the electronic industry because of its special transparent and conductive properties. However, there are a few reports regarding the adsorption of organic or organometallic compounds on the ITO surface1-4. The heteropolyanions are interested in the field of material science, catalytics, biology, and medicine owing to their chemical, structural, and electronic versatility5-7. One of the most important properties of polyoxometalate anions is their ability to a… 相似文献
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Stott SJ Mortimer RJ Dann SE Oyama M Marken F 《Physical chemistry chemical physics : PCCP》2006,8(46):5437-5443
Titanium carbide (TiC) nanoparticles are readily deposited onto tin-doped indium oxide (ITO) electrodes in the form of thin porous films. The nanoparticle deposits are electrically highly conducting and electrochemically active. In aqueous media (at pH 7) and at applied potentials positive of 0.3 V vs. SCE partial anodic surface oxidation and formation (at least in part) of novel core-shell TiC-TiO2 nanoparticles is observed. Significant thermal oxidation of TiC nanoparticles by heating in air occurs at a temperature of 250 degrees C and leads first to core-shell TiC-TiO2 nanoparticles, next at ca. 350 degrees C to TiO2 (anatase), and finally at temperatures higher than 750 degrees C to TiO2 (rutile). Electrochemically and thermally partially oxidized TiC nanoparticles still remain very active and for some redox systems electrocatalytically active. Scanning and transmission electron microscopy (SEM and TEM), temperature dependent XRD, quartz crystal microbalance, and voltammetric measurements are reported. The electrocatalytic properties of the core-shell TiC-TiO2 nanoparticulate films are surveyed for the oxidation of hydroquinone, ascorbic acid, and dopamine in aqueous buffer media. In TiC-TiO2 core-shell nanoparticle films TiO2 surface reactivity can be combined with TiC conductivity. 相似文献
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Two-dimensional gold nanostructures have been fabricated by electrochemical deposition of gold nanoparticles onto indium tin oxide (ITO) glass substrate modified with thin polypyrrole film. By controlling the electrodeposition conditions, gold nanoparticles with dendritic rod, sheet, flower-like (consisting of staggered nanosheets), and pinecone-like structures were generated. The flower-like gold nanoparticles showed high catalytic activity on electrochemical reduction of oxygen, and its activity was measured to be approximately 25 times that of gold pinecones and 10(4) times that of gold nanosheets in terms of gold weight. The pinecone-like nanoparticles can form a compact film with nano-/microscale binary structure like a lotus leaf surface. After modification with n-dodecanethiol, the surface showed superhydrophobic properties with a water contact angle of 153.4 degrees and a tilt angle of 4.4 degrees (5 microL droplet). 相似文献
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Alkanethiol self-assembled monolayers (SAMs) have been used in electrochemical microfabrication processes. The reductive desorption potential of alkanethiol SAMs, Edes, can be comparable to, greater than, or less than the metal reduction potential during electrodeposition, Emet. As a result, the SAM layer can passivate the surface or desorb simultaneously with metal deposition. We show that these electrochemical traits can be combined with a rastering microjet electrode to pattern SAMs directly and create patterned metal films without lithography steps. For the case of copper deposition on 1-octanethiol (OT)- and 1-dodecanethiol (DT)-coated substrates, Edes is significantly negative of Emet, resulting in high-resolution metal patterns with poor nucleation and poor adhesion to the substrate. However, nickel patterns deposited on 1-butanethiol (BT), OT, and DT have traits similar to bare gold (excellent nucleation and adhesion) because Edes is positive of Emet. Substrates with SAMs also suppress adventitious chemistries that occur distant from the rastering microjet electrode, such as oxygen reduction, making samples more corrosion resistant and improving the overall patterning process that we call electrochemical printing. 相似文献
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通过循环伏安法等方法研究了氧化铟锡(ITO)透明导电薄膜的电化学行为. 获得了ITO薄膜在NaOH溶液中阴极和阳极极化处理前后的循环伏安曲线. 采用透射光谱, 方块电阻测试, 扫描电子显微镜(SEM), 能量色散X射线荧光光谱(EDS)与X射线衍射(XRD)表征ITO薄膜经电化学处理后的反应产物. 结果表明, ITO薄膜在阳极处理后(约为+1.5 V(vs SCE))保持了稳定的成分和结构. 但经阴极处理后(约为-1.5 V(vs SCE))发生了严重的电化学腐蚀, 可见光透射率大幅下降, 方块电阻增加一个数量级. 经SEM、EDS和XRD表征分析, 证明阴极处理过程使ITO薄膜中的In3+还原成了In单质. 相似文献
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C. H. Rios-Reyes L. H. Mendoza-Huizar M. Rivera 《Journal of Solid State Electrochemistry》2010,14(4):659-668
In the present work, we analyze the electrodeposition of cobalt by electrochemical techniques onto GCE (system I) and HOPG
(system II) electrodes from sulfate solutions. Cyclic voltammetry and current transient measurements were used to obtain the
nucleation and growth mechanism. The results clearly showed that electrodeposition of cobalt is a diffusion-controlled process
with a typical 3D nucleation mechanism in both substrates. The average ΔG calculated for the stable nucleus formation was 1.97 × 10−20 J nuclei−1 and 3.58 × 10−20 J nuclei−1 for system I and system II, respectively. The scanning electron microscope (SEM) images indicated similar nucleation and
growth processes on GCE and HOPG substrates at same overpotential with a homogeneous disperse cobalt clusters. X-ray energy-dispersive
spectroscopy (EDS) was performed in order to ensure that the clusters formed are cobalt. The nuclei’s size obtained was dependent
of the overpotential applied; at lower overpotentials, the growth rate of the cobalt clusters diminishes when their number
increases due to the strongly reduced concentration of cobalt ions because of their consumption by a larger number of growing
particles. A theoretical quantum study employing PM6 method suggests that Na+ adsorbed deactivate the local surface occasionating the formation of disperse cobalt clusters on carbon electrodes. 相似文献