Laboratory of Chemistry and Electrochemistry of Surfaces (CES), University of Namur (FUNDP), 61 rue de Bruxelles, B-5000 Namur, Belgium.
Langmuir. 2011 Dec 20;27(24):14849-60. doi: 10.1021/la2026957. Epub 2011 Nov 14.
Cobalt and its alloys are used in a broad range of application fields. However, the use of this metal is especially limited by its strongly oxidizable nature. The use of alkanethiol self-assembled monolayers (SAMs) is a very efficient way to protect against such oxidation and/or to inhibit corrosion. This surface modification method has been particularly applied to oxidizable metals such as copper or nickel, yet the modification of cobalt surfaces by alkanethiol SAMs received limited attention up to now. In this work, we study the influence of parameters by which to control the self-assembly process of 1-dodecanethiol monolayers on cobalt: nature of the surface pretreatment, solvent, immersion time, and concentration. Each of these parameters has been optimized to obtain a densely packed and stable monolayer able to efficiently prevent the reoxidation of the modified cobalt substrates. The obtained monolayers were characterized by X-ray photoelectron spectroscopy (XPS), polarization modulation infrared reflection-absorption spectroscopy, and contact angle measurements. The stability of the optimized 1-dodecanethiol monolayer upon air exposure for 28 days has been confirmed by XPS.
钴及其合金在广泛的应用领域中都有使用。然而，这种金属的使用受到其强烈的可氧化性质的限制。使用烷硫醇自组装单分子层（SAM）是防止这种氧化和/或抑制腐蚀的非常有效的方法。这种表面改性方法特别适用于可氧化的金属，如铜或镍，但到目前为止，烷硫醇 SAM 对钴表面的改性受到的关注有限。在这项工作中，我们研究了控制 1-十二硫醇单层在钴上自组装过程的参数的影响：表面预处理的性质、溶剂、浸渍时间和浓度。这些参数中的每一个都经过了优化，以获得能够有效阻止改性钴基底再氧化的密集且稳定的单层。通过 X 射线光电子能谱（XPS）、偏振调制红外反射吸收光谱和接触角测量对获得的单层进行了表征。XPS 证实了优化后的 1-十二硫醇单层在暴露于空气中 28 天后的稳定性。
