Degradation of 2-naphthol in water and antibacterial/antiviral activity by Zn2SnO4, ZnSn(OH)6 and Y2Sn2O7

Abstract

White single-phase powders of Zn2SnO4, ZnSn(OH)6 and Y2Sn2O7 were prepared using hydrothermal method. In the 2-naphthol aqueous solutions in which these powders were immersed, ZnSn(OH)6 and Y2Sn2O7 reduced the 2-naphthol concentration in the dark. The concentration-decreasing rate temperature dependence, the activation energy, and the binding energy change suggested that the oxidative decomposition of 2-naphthol resulted from the Mars – van Krevelen (MvK) mechanism of Sn. Near non-occurrence of ion elution in water was confirmed for these materials, except for Zn in Zn2SnO4. Among these samples, Y2Sn2O7 exhibited the highest antibacterial and antiviral activities against Escherichia coli, Staphylococcus aureus, bacteriophage Qβ, and bacteriophage Φ6 in the dark. Adsorption attributable to electrostatic interactions between cationic samples and bacteria/viruses and the MvK mechanism were expected to lead to protein denaturation and consequently to antibacterial activity and antiviral activity. For Y2Sn2O7, the specific interaction between Y and phosphate ions possibly improved their antibacterial and antiviral activities. This white, non-eluting material was found to have degrees of high antibacterial and antiviral activity.