The present invention provides a material for forming an antimicrobial surface coating with multi-level antimicrobial properties, which comprises one or more volatile or gaseous biocides, one or more nonvolatile biocides, and one or more polymers, wherein the volatile or gaseous biocides are encapsulated in the polymers to provide a sustained release of the volatile or gaseous biocides. The present invention further provides a method for preparing the material.