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In the present work, a hybrid hierarchical coating (HHC) system comprising a plasma electrolytic oxidation (PEO) coating and a homogeneously porous structured polycaprolactone (PCL) top-coat layer, loaded with ciprofloxacin (CIP), was developed on Mg3Zn0.4Ca alloy. According to the findings, the HHC system avoided burst release and ensured gradual drug elution (64% over 240 h). The multi-level protection of the magnesium alloy is achieved through sealing of the PEO coating pores by the polymer layer and the inhibiting effect of CIP (up to 74%). The corrosion inhibition effect of HHC and the eluted drug is associated with the formation of insoluble CIP-Me (Mg/Ca) chelates that repair the defects in the HHC and impede the access of corrosive species as corroborated by FTIR spectra, EIS and SEM images after 24 h of immersion. Therefore, CIP participates in an active protection mechanism by interacting with cations coming through the damaged coating.

A global transition towards more sustainable, affordable and reliable energy systems is being stimulated by the Paris Agreement and the United Nation's 2030 Agenda for Sustainable Development. This poses a challenge for the corrosion industry, as building climate-resilient energy systems and infrastructures brings with it a long-term direction, so as a result the long-term behaviour of structural materials (mainly metals and alloys) becomes a major prospect. With this in mind “Corrosion Challenges Towards a Sustainable Society” presents a series of cases showing the importance of corrosion protection of metals and alloys in the development of energy production to further understand the science of corrosion, and bring the need for research and the consequences of corrosion into public and political focus. This includes emphasis on the limitation of greenhouse gas emissions, on the lifetime of infrastructures, implants, cultural heritage artefacts, and a variety of other topics., QC 20230404

Integrated attenuated total reflection – Fourier transform infrared spectroscopy (ATR-FTIR) – Electrochemical impedance spectroscopy (EIS) measurements were used to simultaneously follow chemisorption mechanisms of organic inhibitors as well as their corrosion inhibition efficiency towards magnesium based substrates. Four carboxylic compounds, i.e. 2,5-pyridinedicarboxylic acid (PDC), 3-methylsalicylic acid (MSA), sodium salicylate (SS) and fumaric acid (FA), were selected based on their promising inhibiting capacities and were all shown to chemisorb at the MgO/Mg(OH)2 surface by carboxylate bond formation. Orientation analysis using polarized infrared light showed that carboxylate bonds established using aliphatic carboxylate compound aligned perpendicular to the magnesium surface, whereas carboxylate bonds with aromatic compounds were oriented in plane with the magnesium surface. This different orientation is associated to the involvement of π-interactions in the MgO/Mg(OH)2 – aromatic carboxylate adsorption. Additionally, DFT calculations revealed that the addition of hetero-atoms (i.e. N or OH) in the molecular structure contributes to increased adsorption energies, indicating that next to carboxylate groups also these hetero-atoms are involved in interfacial interactions. Integrating the ATR-FTIR setup with an electrochemical cell allowing for simultaneous EIS measurements lead to two surface phenomena determining the inhibition efficiency. Surface hydroxylation processes on one hand forming a MgO/Mg(OH)2 layer on one hand, and the chemisorption of carboxylate compounds on the other hand. The inhibition efficiency was found to increase in following order: FA < PDC < MSA and was mainly associated to the formation of a MgO/Mg(OH)2 layer. SS was shown to act as a corrosion accelerator rather than a corrosion inhibitor. Despite its high sensitivity for water, both surface processes could be followed in situ by me, (OLD) MSE-6

Nanocrystalline La0.9A0.1MnO3 (where A is Li, Na, K) powders were synthesized by a combustion method. The powders used to prepare nanoceramics were fabricated via a high-temperature sintering method. The structure and morphology of all compounds were characterized by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). It was found that the size of the crystallites depended on the type of alkali ions used. The high-pressure sintering method kept the nanosized character of the grains in the ceramics, which had a significant impact on their physical properties. Magnetization studies were performed for both powder and ceramic samples in order to check the impact of the alkali ion dopants as well as the sintering pressure on the magnetization of the compounds. It was found that, by using different dopants, it was possible to strongly change the magnetic characteristics of the manganites. © 2020 by the authors.

One of the main applications of SVET in corrosion research is the study of the corrosion inhibition effectiveness and the evaluation of the self-healing effect of inhibitor-containing coatings. The tip of the platinum/iridium vibrating electrode is electroplated with black platinum, which creates a large electrode surface and confers high capacitance to the tip. When studying organic inhibitors in aqueous solutions with SVET, inhibitor adsorption may occur at the tip, causing its contamination and the initial calibration conditions of the system might not be valid. This may lead to an incorrect interpretation of the results. This work is intended to study the effect of different inhibitors (cerium nitrate, 8-hydroxyquinoline, potassium 2,5-dimercapto-1,3,4-thiadiazolate, benzotriazole and mercaptobenzothiazole), typically used for corrosion protection of aluminum alloys, on the Pt probe signal during SVET measurements. The results reveal the detrimental effect of some corrosion inhibitors on the sensitivity of the vibrating probe, an effect that imposes a regular assessment of the electrode state during measurements. The increase of the signal noise was related to a decrease of the probe capacitance, while the false current density signal was a result of the potential drift between vibrating and reference electrodes., Accepted Author Manuscript, (OLD) MSE-6

Four bioactive PEO (plasma electrolytic oxidation) coatings were generated on Mg0.8Ca alloy using a Ca/P-based electrolyte and adding Si or Fas necessary. Surface characteristics, chemical composition and ion liberation of the coatings were characterized using SEM/EDS (Scanning Electron Microscopy/Energy Dispersive X-ray spectroscopy), X-ray diffraction, optical profilometry and ICP-OES (inductively coupled plasma optical emission spectrometry). Direct biocompatibility studies were performed by seeding premyoblastic, endothelial and preosteoblastic cell lines over the coatings. Biocompatibility of the coatings was also evaluated with respect to murine endothelial, preosteoblastic, preosteoclastic and premyoblastic cell cultures using extracts obtained by the immersion degradation of the PEO-coated specimens. The coatings reduced the degradation of magnesium alloy and released Mg Ca, P, Si and F. Of all the studied compositions, the Si-containing PEO coating exhibited the optimal characteristics for use in all potential applications, including bone regeneration and cardiovascular applications. Coatings with high F content negatively influenced the endothelial cells. RAW 264.7, MC3T3 and co-culture differentiation studies using extracts of PEO coated Mg0.8Ca demonstrated improved osteoclastogenesis and osteoblastogenesis processes compared to bare alloy.

In the current paper the corrosion inhibition synergy between Ce3+ loaded NaY-zeolite (NaY-Ce) and 2-Mercaptobenzothiazole (MBT) loaded Zn-Al layered double hydroxide (LDH-MBT) containers is presented. Solutions and water-borne epoxy coatings containing different ratios of the two loaded carriers were prepared and their protection of AA2024-T3 and damaged coatings characterized using global and local electrochemical techniques and other complementary tools. The coatings containing container-combinations showed exceptional corrosion protection over a broad range of NaY-Ce:LDH-MBT weight ratios, with 90:10 being the optimal. The current work landmarks the need for synergetic inhibiting studies devoted to carrier-inhibitor systems in coatings., Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., Novel Aerospace Materials