标题：A simple and convenient method to fabricate new types of phytic acid-metal conversion coatings with excellent anti-corrosion performance on the iron substrate
作者：Yan, Ru; Gao, Xiang; He, Wei; Guo, Rui; Wu, Ruonan; Zhao, Zhuangzhi; Ma, Houyi
作者机构：[Yan, Ru; He, Wei; Guo, Rui; Wu, Ruonan; Zhao, Zhuangzhi; Ma, Houyi] Shandong Univ, Sch Chem & Chem Engn, Key Lab Colloid & Interface Chem, State Educ 更多
通讯作者地址：[Ma, HY]Shandong Univ, Sch Chem & Chem Engn, Key Lab Colloid & Interface Chem, State Educ Minist, Jinan 250100, Shandong, Peoples R China.
摘要：A simple and practical method was developed to prepare a series of phytic acid (PA)-metal complex coatings on iron substrate by directly immersing the iron samples in the mixed solutions containing PA and metal ions. The key technologies of fabricating PA-metal complex coatings include: (i) anchoring of PA molecules onto the iron surface via complexation with Fe2+ ions dissolved from the iron substrate, and (ii) layer-by-layer deposition of PA-metal complexes on the PA/Fe2+ bottom layer through the bridging effect of additive metal ions. The present method was applicable to the film-forming process of a variety of metal ions, such as Zn2+, Ca2+, Co2+ and Ni2+, and the as-prepared PA-metal complex coatings were defined as PA-M conversion coatings (M = Zn2+, Ca2+, Co2+ and Ni2+ herein). Due to the strong coordination ability, PA molecules may be self-assembled on the iron surface, forming a layer of organic thin film (here defined as PA film), without the help of additive metal ions. However, the comparison between PA film and PA-M coatings shows that PA-M coatings were much thicker (over 15 mm) and denser and also possessed much stronger anti-corrosion performance compared to the PA film. The present study provides a new path for the fabrication of environmentally-friendly PA-based chemical conversion coatings and further broadens the application range of PA in metal surface pretreatment.