On the electrodeposition of hard gold
On the electrodeposition of hard gold
复制标题
关于硬金的电沉积
DOI：
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发表时间：
1979
期刊：
影响因子：
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通讯作者：
N. Ibl
中科院分区：
文献类型：
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作者：
H. Angerer;N. Ibl
研究了在2μm层中电沉积硬质金的过程。电解液为酸性柠檬酸盐浴(pH 3.5)，添加剂为钴。流动池允许水动力条件的受控变化。实验中定量考察了镀金的电流效率(10-30%)、镀层的碳含量、钴含量、孔隙率和形貌[扫描电子显微镜(SEM)]。在50 mA cm−2以上，金的沉积和少量的钴的结合变得限制了质量传输(由于扩散层的复杂性质而产生了某些并发症)。在50 mA cm−2以下观察到的影响似乎是由于输运控制的溶解氧还原的协同效应。提出了一个简单的碳掺入的定性模型。在镀液中加入钴后，电流效率显著下降，这可能是由于氢过电位的降低和镀金过电位的增加所致。从技术应用的角度来看，最相关的结果是，随着电流密度(C.D.)的降低，孔隙率显著减少。和提高流速。
The electrodeposition of hard gold in layers of 2 μm was investigated. The electrolyte was an acid citrate bath (pH 3·5) with cobalt as an additive. A flow cell allowed a controlled variation of the hydrodynamic conditions. The following features were examined quantitatively in the experiments: the current efficiency for gold deposition (10–30%), the carbon and cobalt content, as well as the porosity of the deposits, and the morphology [by scanning electron microscope (SEM)]. Above 50 mA cm−2 the deposition of gold and to a minor extent the incorporation of cobalt become mass transport limited (with certain complications resulting from the complex nature of the diffusion layer). The influence observed below 50 mA cm−2 seems to be due to the synergic effect of the transport controlled reduction of dissolved oxygen. A simple qualitative model for the incorporation of carbon is proposed. The substantial decrease in current efficiency observed upon the addition of cobalt to the bath is probably causedboth by a decrease of the hydrogen overpotential and by an increase of the overpotential for gold deposition. From the viewpoint of technical application, the most relevant result, is the substantial decrease in porosity at decreasing current density (c.d.) and increasing flow rate.