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121.
Electroactive conducting polymers for corrosion control 总被引:1,自引:0,他引:1
Dennis E. Tallman Geoff Spinks Anton Dominis Gordon G. Wallace 《Journal of Solid State Electrochemistry》2002,6(2):73-84
There is an intensive effort underway to develop new corrosion control coatings for structural metals. In part, this effort
has been motivated by the desire to replace chromium(VI)-containing coatings currently used for corrosion control of iron
and aluminum alloys. Cr(VI) has been shown to be hazardous to the environmental and to human health, and its use in many countries
will be sharply curtailed in the coming years. Electroactive conducting polymers (ECPs) represent a class of interesting materials
currently being explored for use in corrosion control coating systems, possibly as a replacement for Cr(VI)-based coatings.
The electroactivity and the electronic conductivity (or semiconductivity) of ECPs set them apart from traditional organic
coatings. As with chromate, interesting and potentially beneficial interactions of ECPs with active metal alloys such as steel
and aluminum are anticipated, with concomitant alteration of their corrosion behavior. A review of this active research area
will be presented in two parts. Here in Part 1, a general introduction to the topic of corrosion control by ECPs will be presented,
including an overview of corrosion and its control by traditional methods, an introduction to ECPs and their properties, and
a discussion of the processing issues surrounding the use of ECPs as coatings. Part 1 also includes a review of the literature
on the use of ECPs as coatings (or components of coatings) on non-ferrous active metals, principally aluminum and aluminum
alloys, although some work on zinc, copper, silver, titanium and silicon will also be described. In Part 2 of this review
(to be published in the next issue of this journal), the rather extensive literature on the use of ECPs for the corrosion
control of ferrous alloys (steels) will be reviewed.
Electronic Publication 相似文献
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Sheng Yang Guangbo Chen Antonio Gaetano Ricciardulli Panpan Zhang Zhen Zhang Huanhuan Shi Ji Ma Jian Zhang Paul W. M. Blom Xinliang Feng 《Angewandte Chemie (International ed. in English)》2020,59(1):465-470
Transition‐metal phosphides (TMPs) have emerged as a fascinating class of narrow‐gap semiconductors and electrocatalysts. However, they are intrinsic nonlayered materials that cannot be delaminated into two‐dimensional (2D) sheets. Here, we demonstrate a general bottom‐up topochemical strategy to synthesize a series of 2D TMPs (e.g. Co2P, Ni12P5, and CoxFe2?xP) by using phosphorene sheets as the phosphorus precursors and 2D templates. Notably, 2D Co2P is a p‐type semiconductor, with a hole mobility of 20.8 cm2 V?1 s?1 at 300 K in field‐effect transistors. It also behaves as a promising electrocatalyst for the oxygen evolution reaction (OER), thanks to the charge‐transport modulation and improved surface exposure. In particular, iron‐doped Co2P (i.e. Co1.5Fe0.5P) delivers a low overpotential of only 278 mV at a current density of 10 mA cm?2 that outperforms the commercial Ir/C benchmark (304 mV). 相似文献
125.
Electrolytic Formation of Crystalline Silicon/Germanium Alloy Nanotubes and Hollow Particles with Enhanced Lithium‐Storage Properties 下载免费PDF全文
Dr. Wei Xiao Jing Zhou Dr. Le Yu Prof. Dihua Wang Prof. Xiong Wen Lou 《Angewandte Chemie (International ed. in English)》2016,55(26):7427-7431
Crystalline silicon(Si)/germanium(Ge) alloy nanotubes and hollow particles are synthesized for the first time through a one‐pot electrolytic process. The morphology of these alloy structures can be easily tailored from nanotubes to hollow particles by varying the overpotential during the electro‐reduction reaction. The continuous solid diffusion governed by the nanoscale Kirkendall effect results in the formation of inner void in the alloy particles. Benefitting from the compositional and structural advantages, these SiGe alloy nanotubes exhibit much enhanced lithium‐storage performance compared with the individual solid Si and Ge nanowires as the anode material for lithium‐ion batteries. 相似文献
126.
采用真空电弧熔炼及退火处理制备R-Y-Ni系A_2B_7型R0.3Y0.7Ni3.25Mn0.15Al0.1(R=Y,La,Pr,Ce,Nd,Gd,Sm)储氢合金,系统研究稀土元素R对合金微观组织与结构、储氢和电化学性能的影响。XRD和SEM-EDS分析表明,合金退火组织由Ce2Ni7型主相、PuNi3型及少量Ca Cu5型相组成,Ce2Ni7型主相的晶格常数a、c及晶胞体积V均随稀土R原子半径的减小而依次降低。该合金均具有明显的吸放氢平台,常温下最大吸氢容量为1.17%~1.48%(w/w),吸氢平台压Peq为0.037~0.194 MPa。电化学分析表明,退火合金电极的电化学活化性能优良,R=La合金具有最高的放电容量(389.2 mAh·g-1)和较佳的容量保持率(充放电循环100次后的S100=85.7%),其中合金微观组织的不均匀性及稀土元素的电化学腐蚀是影响电极循环稳定性的主要原因。合金电极的高倍率放电性能(电流密度为900 m A·g-1)HRD900=71.05%~86.94%,其电极反应动力学控制步骤主要由氢原子在合金体相中的扩散速率所控制。 相似文献
127.
镍钛记忆合金自补偿磨粒磨损性能研究 总被引:3,自引:3,他引:3
研究了高临界温度镍钛记忆合金一维自补偿磨粒磨损特性.结果表明,在一定温度下,镍钛记忆合金在摩擦过程中具有形状恢复能力,从而产生一维磨损自补偿作用.超弹状态镍钛记忆合金具有热弹性马氏体相变、高阻尼、应力感生马氏体、超弹性、高应变硬化指数和时效弥散析出强化等特性,这使得硬度较低的镍钛合金的耐磨性能远优于硬度较高的淬火45#钢.利用超弹状态镍钛记忆合金的磨损自补偿作用可望开发出新型抗磨形状记忆合金产品. 相似文献
128.
129.
K. Thommen 《辐射效应与固体损伤》2013,168(3):201-210
Undoped n-type GaAa was irradiated near 5 and 77 °K with electrons having incident energies between 0.46 and 1.30 MeV. The recovery of the electrical resistivity and the Hall coefficient upon annealing from 4 to 520 °K was monitored. Changes which occurred upon annealing below 200 °K could be reversed by ionizing radiation. A small amount of irreversible ionization-induced recovery was observed after irradiation near 5 °K. Major irreversible recovery stages were centered near 235 (stage I), 280 (stage II) and 520 °K (stage III). Recovery in stage I and II obeyed first order kinetics. The activation energies of stages I and II were determined as 0.72 and 0.83 eV, respectively. The carrier concentration changes per unit irradiation dose corresponding to the three recovery stages differed in their energy dependence indicating that the defects which are removed in stage III have the lowest threshold energy. The carrier concentration changes per unit irradiation dose corresponding to stages I and III were higher for irradiation near 5 °K than for irradiation near 77 °K. 相似文献
130.
A new method for the spectrofluorimetric determination of indium by formation of a fluorescent 1:1 complex with 1,2,4-trihydroxyanthraquinone is proposed. The complex is formed in a mixed, 60:40 v/v acetone-water medium at pH 3.8 provided by an acetic acid-sodium acetate buffer. The calibration graph is linear between 10 and 600 ng/ml. The effect of potential interferents on the determination was assessed and the proposed method was applied to the determination of indium in synthetic samples. 相似文献