An antimicrobial ceramic glazing composition contains one or more antimicrobial agents disposed therein. Methods for making and using the glazing composition are disclosed, as well as substrates having a fired antimicrobial glaze thereon. The antimicrobial agents comprise metallic oxides, with a subset of the disclosed combinations exhibiting synergistic effect in fired glazes.

A method for forming an oxide coated substrate comprising heating a pre-coating mixture in the presence of a substrate to synthesize an oxide coating on the substrate. The pre-coating mixture comprises a solubilized reducing additive, a solubilized oxidizing additive, and the substrate. The heating is conducted at a temperature sufficiently high enough to exothermically react the solubilized reducing additive and solubilized oxidizing additive and low enough to control the phase and composition of the oxide.

A method for forming an oxide coated substrate comprising heating a pre-coating mixture in the presence of a substrate to synthesize an oxide coating on the substrate. The pre-coating mixture comprises a solubilized reducing additive, a solubilized oxidizing additive, and the substrate. The heating is conducted at a temperature sufficiently high enough to exothermically react the solubilized reducing additive and solubilized oxidizing additive and low enough to control the phase and composition of the oxide.