Preparation of Zirconium Hydrogen Phosphate Coatings on Sandblasted/Acid-Etched Titanium for Enhancing Its Osteoinductivity and Friction/Corrosion Resistance

Design Polyaniline/α-Zirconium Phosphate Composites for Achieving Self-Healing Anti-Corrosion of Carbon Steel

The rupture of a micro/nano container can trigger the release of repair agents and provides the coating with a self-healing and anti-corrosion effect. However, the defect and inhomogeneity of the coating, produced by the rupture of the micro/nano container, may weaken its anti-corrosion performance. This study reports a rare protection mechanism, which optimizes the space occupying of zirconium phosphate, and the de-doping peculiarity of polyaniline without the rupture of the micro/nano container. Polyaniline/α-zirconium phosphate composites were constructed through in situ oxidation polymerization. Repair agents were added in the form of doped acids. According to the different repair agents in polyaniline/α-zirconium phosphate composites (citric ion, tartaric ion and phytic ion), the performance and protection mechanism of the composites were researched. Polyaniline/α-zirconium phosphate coating (with phytic ion) shows an excellent self-healing anti-corrosive effect, due to the large spatial structure and abundant chelating groups of the precipitation inhibitor. Considering the anti-corrosive application, the developed polyaniline/α-zirconium phosphate composite has a far-reaching influence on marine development.

Improvement in osteogenesis, vascularization, and corrosion resistance of titanium with silicon-nitride doped micro-arc oxidation coatings

Titanium (Ti) implants have been widely used for the treatment of tooth loss due to their excellent biocompatibility and mechanical properties. However, modifying the biological properties of these implants to increase osteointegration remains a research challenge. Additionally, the continuous release of various metal ions in the oral microenvironment due to fluid corrosion can also lead to implant failure. Therefore, simultaneously improving the bioactivity and corrosion resistance of Ti-based materials is an urgent need. In recent decades, micro-arc oxidation (MAO) has been proposed as a surface modification technology to form a surface protective oxide layer and improve the comprehensive properties of Ti. The present study doped nano silicon nitride (Si₃N₄) particles into the Ti surface by MAO treatment to improve its corrosion resistance and provide excellent osteoinduction by enhancing alkaline phosphatase activity and osteogenic-related gene expression. In addition, due to the presence of silicon, the Si₃N₄-doped materials showed excellent angiogenesis properties, including the promotion of cell migration and tubule formation, which play essential roles in early recovery after implantation.