Synthesis of a non-hazardous/smart anti-corrosion nano-carrier based on beta-cyclodextrin-zinc acetylacetonate inclusion complex decorated graphene oxide (β-CD-ZnA-MGO)

摘要

Recently, the high research considerations have been devoted to designing smart coatings with self-healing propensity along with improved anti-corrosion properties, durability, and effectiveness. In the present work, a novel nano-container, namely beta-cyclodextrin (beta-CD), was introduced and applied for encapsulating and subsequent controlled release of a metal-organic inhibitor, namely zinc acetylacetonate (ZnA) in the polymeric matrix. The smart release is another principal object which has been lacked in recent reports. For this aim, graphene oxide nanoparticles were employed to carry the inclusion complexes (beta-CD-ZnA) to the defected zones of coatings. FT-IR, Raman, XRD, and UV-vis experiments ascertained that the beta-CD-ZnA inclusion complex successfully adsorbed onto the GO sheets modified by 3-aminopropyl tri-ethoxysilane (MGO). The electrochemical inspections (i.e., potentiodynamic polarization and EIS) proved that the beta-CD-ZnA-MGO particles could remarkably inhibit the steel corrosion in 3.5 % NaCl solution via mixed cathodic/anodic retardation mechanisms with approximately 93 % efficiency after 48 h metal exposure. It was also found that the corrosion protection performance of the polymeric matrix loaded by beta-CD-ZnA-MGO nano-particles enhanced markedly, assigning to the significant epoxy defect coverage by beta-CD-ZnA. The intelligent transmission was affirmed by EDS-mapping analysis in the defected regions of epoxy coating. The high quantity of the Zn element ensured the successful adsorption of the ZnA on the metal surface. The damage, as well as the delaminated degrees of the un-scratched epoxy coating, was estimated by the EIS experiment outcomes. Achievements reflected that the presence of beta-CD-ZnA-MGO nano-filler in the epoxy resin matrix significantly reduced the electrolyte/ion diffusion.