Anti-bacterial property of Si and F doped diamond-like carbon coatings

•A range of Si and F doped diamond-like carbon (DLC) coatings were prepared.•The contact angle and surface energy of the doped DLC coatings were measured.•The doped DLC coatings reduced the surface energy of DLC coatings.•The coatings reduced bacterial adhesion by 68%, compared with the stainless steel.

In this study, the anti-bacterial performance of modified diamond-like carbon (DLC) coatings with Si and F was investigated and compared with standard DLC coatings and stainless steel using Klebsiella pneumoniae as test bacterium. The experimental results indicated that the F and Si doped DLC coatings reduced the surface energy and improved anti-bacterial ability of DLC coatings. The extended DLVO theory was used to calculate the interaction energy between the coatings and the bacterium. The anti-bacterial mechanism was explained using the extended theory.