Petrova E, Serdechnova M, Shulha T, Lamaka S V, Wieland D C F, Karlova P, Blawert C, Starykevich M, Zheludkevich M L
Faculty of Chemistry, Belarusian State University, Nezavisimosti Avenue 4, 220030, Minsk, Belarus.
MagIC-Magnesium Innovation Center, Helmholtz-Zentrum Geesthacht, Max-Planck-Straβe 1, 21502, Geesthacht, Germany.
Sci Rep. 2020 May 26;10(1):8645. doi: 10.1038/s41598-020-65396-0.
The principal possibility to grow layered double hydroxide (LDH) at ambient pressure on plasma electrolytic oxidation (PEO) treated magnesium alloy AZ91 in the presence of chelating agents is demonstrated for the first time. It avoids hydrothermal autoclave conditions, which strongly limit wide industrial application of such coating systems, and the presence of carbonate ions in the electrolyte, which lead to the formation of "passive" non-functionalizable LDH. A combination of chelating agents (sodium diethylenetriamine-pentaacetate (DTPA) and salicylate) were introduced to the treatment solution. The role of each additive and the influence of treatment bath composition on the LDH formation processes are discussed. A synergistic effect of DTPA and salicylate during LDH formation is discovered and its possible explanation is proposed.
首次证明了在常压下，在螯合剂存在的情况下，在等离子体电解氧化（PEO）处理的AZ91镁合金上生长层状双氢氧化物（LDH）的主要可能性。这避免了水热高压釜条件，水热高压釜条件严重限制了此类涂层系统的广泛工业应用，也避免了电解液中碳酸根离子的存在，碳酸根离子会导致形成“钝化”的不可功能化LDH。将螯合剂（二乙烯三胺五乙酸钠（DTPA）和水杨酸盐）的组合引入处理溶液中。讨论了每种添加剂的作用以及处理浴组成对LDH形成过程的影响。发现了DTPA和水杨酸盐在LDH形成过程中的协同效应，并提出了其可能的解释。
