Elaboration of hybrid bionic coatings introducing natural components as chitosan and/or hydroxiapatite on the modified surfaces of Zr with 1D nanoarchitectures

Daniela Ionita, Andrei Bogdan Stoian, Ioana Demetrescu

General Chemistry Department University Politehnica of Bucharest, Romania

The available literature on pure Zr is scarce and coated Zr has largely an unknown behavior. For the development of potential bioapplications of Zr especially in dentistry there is a needof more knowledge based on investigations and understanding of bio and non biointeractions between natural materials and living organisms. The present study aims on building and testing complex hybrid architectures such as micro and nanocoatings on Zr using a simple procedures such as anodizing. The mechanism of self-organized layer of zirconiananotubes by anodizing is controlled by factors such as fluoride content, pH, temperature and applied voltage. Due to process polarisation of the Zr–O bonds, pits formation in the anodizing process occur randomly on the oxide surface and became centres of pore nucleation. Under suitable voltage, the pores formation will reach a steady-state resulting in a surface completely covered in pores or in a surface covered in self organized nanotubes.

This study has as initial point nanostructure fabricated at 30 and 60 V in a mixture of fluorinated ethylene glycol electrolyte with the addition of K2CO3 After annealing, the second step was electrochemical elaboration of hybrid complex coatings introducing natural components as chitosan and hydroxiapatite. The main part of the investigation includes the characterization of the coatings fabricated on ZrO2 nanostructure. The obtained nanostructures formed on ZrO2 oxides have been identified with infrared analysis(IR) ,scanning electron microscopy (SEM) coupled with an energy dispersive module (EDX), atomic force microscopy (AFM), and with X-ray diffraction (XRD). The surface analysis was completed with wettability and roughness determinations.