Department of Ceramics and Glass Engineering, University of Aveiro, CICECO, 3810-193 Aveiro, Portugal.
ACS Appl Mater Interfaces. 2009 Oct;1(10):2353-62. doi: 10.1021/am900495r.
Zn-Al and Mg-Al layered double hydroxides (LDHs) loaded with quinaldate and 2-mercaptobenzothiazolate anions were synthesized via anion-exchange reaction. The resulting compounds were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy/energy-dispersive X-ray spectroscopy. Spectrophotometric measurements demonstrated that the release of organic anions from these LDHs into the bulk solution is triggered by the presence of chloride anions, evidencing the anion-exchange nature of this process. The anticorrosion capabilities of LDHs loaded with organic inhibitors toward the AA2024 aluminum alloy were analyzed by electrochemical impedance spectroscopy. A significant reduction of the corrosion rate is observed when the LDH nanopigments are present in the corrosive media. The mechanism by which the inhibiting anions can be released from the LDHs underlines the versatility of these environmentally friendly structures and their potential application as nanocontainers in self-healing coatings.
负载喹哪啶和 2-巯基苯并噻唑阴离子的 Zn-Al 和 Mg-Al 层状双氢氧化物（LDHs）通过阴离子交换反应合成。所得化合物通过 X 射线衍射、傅里叶变换红外光谱和扫描电子显微镜/能谱进行了表征。分光光度测量表明，这些 LDHs 中的有机阴离子向本体溶液中的释放是由氯离子的存在引发的，证明了该过程的阴离子交换性质。通过电化学阻抗谱分析了负载有机抑制剂的 LDHs 对 AA2024 铝合金的耐腐蚀性能。当 LDH 纳米颜料存在于腐蚀性介质中时，观察到腐蚀速率显著降低。抑制剂阴离子可以从 LDHs 中释放的机制强调了这些环保结构的多功能性及其作为自修复涂层中纳米容器的潜在应用。
