Microscopic Structure and Binding Mechanism of the Corrosion-Protective Film of Oleylpropanediamine on Copper in Hot Water
Microscopic Structure and Binding Mechanism of the Corrosion-Protective Film of Oleylpropanediamine on Copper in Hot Water
复制标题
热水中铜表面油基丙二胺腐蚀保护膜的微观结构和结合机制
DOI：
10.1021/acs.jpcc.2c00526
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
Nakahara Masaru
中科院分区：
文献类型：
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作者：
Yoshioka Haruka;Yoshida Ken;Noguchi Naoki;Ueki Tomoyuki;Murai Kei-ichiro;Watanabe Kazuya;Nakahara Masaru
采用定量核磁共振和表面表征相结合的方法，研究了150℃水中油基丙二胺(Olda)在金属铜表面的成膜结构。我们通过精确测定所考察系统中的所有质量平衡，成功地量化了成膜量。2D IR显微图谱显示，薄膜厚度在水平方向上不均匀，其长度尺度为∼100μm，并有数百个Olda层。原子力显微镜也证实了这一膜厚。C-H伸缩振动频率的分析表明，烷基链在靠近铜表面的层中高度有序，在远离铜表面的层中构象无序，在薄膜的较厚部分。结合Ar气体团簇离子束刻蚀XPS测量和电感耦合等离子体发射光谱分析，我们揭示了多重层化的关键是Olda的非质子化氨基与铜形成的配位络合物，这可能导致了聚合物链状网络结构。在不同OLDA浓度和不同处理时间下的接触角测量表明，膜的憎水性能源于OLDA分子具有无序疏水链的厚层。
The structure of the film formed by oleylpropanediamine (OLDA) on the copper (Cu) metal surface in water at 150 °C was investigated by combining quantitative NMR and surface characterization methods. We succeeded in quantifying the amount of film formation by precisely determining all mass balances in the systems examined. 2D IR microscopic mapping showed that the film thickness is uneven in the horizontal direction with a length scale of ∼100 μm and hundreds of OLDA layers. This film thickness was also confirmed by AFM. The analysis of the C–H stretching vibrational frequency disclosed that the alkyl chains are highly ordered in the layers close to the Cu surface and are conformationally disordered in the layers distant from the Cu surface in the thicker portion of the film. Combining XPS measurements using argon gas cluster ion beam etching with the ICP-AES analysis, we revealed that the key to multiple layering is the formation of a coordination complex of the unprotonated amino groups of OLDA with Cu that presumably results in polymer chain-like network structures. Contact angle measurements at different OLDA concentrations and treatment times showed that the water repellency of the film originated from the thick layering of OLDA molecules with disordered hydrophobic chains.