Morphological Effect of ZIFs as the Promotion of Surface-Potential-Adsorption for Antibacterial Performance

ZIFs of different morphologies were synthesized by different solvents. Three types of ZIFs with different morphologies, ZIF-M, ZIF-P, and ZIF-L, were prepared using anhydrous methanol, polyethylene glycol-400, and water as solvents, respectively. The morphologies of ZIF-M and ZIF-L are rhombic dodecahedron and blade-like, respectively. Wherein the ZIF-M sample using methanol as solvent has an unusual morphology of high internal specific surface and pore volume. The ZIFs were characterized by XRD, SEM, AAS, N₂ adsorption isotherms, pore size distribution, and evaluated with S. aureus and E. coli to gain antibacterial activity. Using the determination of growth curves, plate counting method and circle of inhibition method, the results showed that ZIF-M like has high antibacterial properties for ZIF-L and ZIF-P. Folding and rupture of the cell walls of dead bacteria was found by measuring the SEM of the bacteria. ZIF-M has the largest specific surface area, better potential properties and highest Zn²⁺ release, which leads to the high antibacterial effect of ZIF-M.