Influence of high temperature on antibacterial property of silver-loaded zeolite

Influence of high temperature on the antibacterial property of silver-load zeolite (Ag-Z) was investigated. The structure change of Ag-Z with variation of temperature was studied by X-ray diffraction (XRD). The optical properties of Ag-Z were analyzed by ultraviolet-visible diffuse reflection spectrum (UV-VIS DRS). The antibacterial property of Ag-Z was characterized by minimum inhibition concentration (MIC). When the temperature is lower than 200°C, a few silver ions in Ag-Z are assembled to form atom clusters, and there is no change in its MIC. As the temperature increases, more and more silver ions are diffused to the outside surface of Ag-Z and are assembled to form atom clusters, resulting in a decline in the antibacterial property of Ag-Z. When the temperature reaches 800°C, almost all silver ions are reduced to form atom clusters and the cavity structure of zeolite is destroyed, thus preventing silver ions from contacting bacteria and dramatically reducing the antibacterial activity.