Synergistic antimicrobial and surface free energy of sol–gel coatings containing fluorosilanes and quaternary ammonium salts

•A two component hybrid polysiloxane was formulated and surface analyzed.•Fluorosilane and antimicrobial additives were incorporated to modify surface.•Inclusion of both additives provided synergistic effect on coatings properties.•Effects arises from increase in both the micro and nanoscale roughness.•These properties provide coating with CWS resistance and antimicrobial properties.