A B S T R A C T Nanohybrid membranes based on the Keggin-type polyoxometalate (POM) H 5 PV 2 Mo 10 O 40 and aminosilanemodified silicate (Ormosil and Ormosil(NR 4 + Cl − )) hybrids were synthesized as a new barrier to protect against simulants of chemical and biological toxicant. The 31 P NMR and XPS results indicated that POM was bound to the Ormosil and Ormosil(NR 4 + Cl − ) hybrids after impregnation. The antibacterial effects of the hybrids and hybrid-impregnated fabrics against Gram-negative and Gram-positive bacteria were investigated with zone of inhibition, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and platecounting method. The MIC/MBC values of Ormosil(NR 4 + Cl − )/POM and Ormosil/POM against bacteria were 0.267/2.67 and 2.67/26.7, respectively, and the percentage reduction of bacteria was approximately 100% after 20 laundry cycles of their fabrics. The reaction products and mechanisms of the adsorptive degradation of 2chloroethylethylsulfide (CEES) by hybrids were investigated with 13 C NMR. The results of this study showed that POM-doped Ormosil systems are capable of destroying bacteria and CEES. + Cl − )/POM hybrids, have proved advantageous as a new type of insoluble antimicrobial polymer, because they have a greater antimicrobial activity and better durability in water than other conventional antimicrobial polymers. They have proved kill a broad range https://doi.