Multi-layer SiC/Mg and F co-substituted hydroxyapatite/chitosan bioactive coating for carbon fibers

• Multi-layer SiC/MFHA/chitosan bioactive coating is synthesized successfully.
• The SiC inner layer with squamous shape works as a bonding and buffer layer.
• SiC/MFHA/chitosan coating exhibits excellent in-vitro bioactivity.

A multi-layer coating composed of SiC inner-layer and Mg and F co-substituted hydroxyapatite/chitosan hybrid out-layer for carbon fibers has been synthesized using a combination method of chemical vapor deposition, electrochemical deposition and ion exchange method. The morphology, microstructure and in-vitro bioactivity of the multi-layer coating are analyzed. The results show that the SiC inner-layer exhibits a squamous shape. Mg and F co-substituted hydroxyapatite/chitosan hybrid out-layer covers the SiC inner-layer coated carbon fiber entirely and uniformly with a flat structure. The multi-layer coating could induce the precipitation of particle-shaped apatite crystals with Ca/P molar ratios of 1.34–1.51 on its surface in simulated body fluid. The multi-layer SiC/Mg and F co-substituted hydroxyapatite/chitosan coated carbon fibers should have potential application for tissue engineering.