Effect of Temperature on the Adhesion and Bactericidal Activities of Ag⁺-Doped BiVO₄ Ceramic Tiles

The aim of this research was to study the effect of temperature on the adhesion and disinfection activities of an Ag⁺-doped BiVO₄ (Ag⁺/BiVO₄) coating. Ag⁺/BiVO₄ was prepared by a sol–gel method, and spraying was used as the deposition method of coating. X-ray diffraction patterns showed that the monoclinic scheelite phase of the samples was unchanged by annealing at 450–650 °C. Scanning electron microscopy results showed that, at high temperatures, the particles melted and formed a dense coating, and the roughness of the coating decreased after initially increasing. The adhesion and disinfection activities were evaluated by ASTM D3359-08 and disinfection experiments. The results showed that the samples modified by silver had a good disinfection activity when annealed in the range of 450–650 °C. The adhesion increased upon increasing the annealing temperature. The sample annealed at 650 °C showed the best coating adhesion and completely killed <i>Escherichia coli</i>, <i>Staphylococcus aureus</i>, <i>Shigella</i>, and <i>Salmonella</i> after 2 h of visible-light irradiation.