Preparation and antibacterial activity of Zn coating on pure Ti with enhanced adhesion

A titania nanotubes layer was prepared as an intermediate layer on pure Ti via anodic oxidation, and subsequently, a Zn-containing coating was electrochemically deposited. The influence of the deposition parameters on the Zn content was studied using an orthogonal experiment. The obtained coatings were characterized using scanning electron microscopy, energy-dispersive spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy, and their adhesion was measured using a scratch test. The deposition time had the greatest effect on the Zn content of the electrodeposited samples, whereas the deposition temperature had the smallest effect. After the electrodeposition, Zn was uniformly distributed on the surface and existed mainly as a simple substance. The adhesion was only 10.9 N in the Zn-free sample; it increased with increasing Zn content of the samples, and reached a maximum value of 22.4 N in the sample with a Zn content of approximately 16%. The samples with Zncontaining coatings exhibited strong antibacterial effects against E. coli and S. aureus, and the antibacterial effect increased with increasing Zn content. Cell viability was above 80%, indicating that the Zn-containing coating is a good candidate as an antibacterial coating for biomedical applications.