Mg–Al mixed metal oxide film derived from layered double hydroxide precursor film: Fabrication and antibacterial properties

Abstract

Mg–Al layered double hydroxide (LDH) precursor films are fabricated in situ by urea hydrolysis using pure Al as both the substrate and Al source. X-ray diffraction patterns and scanning electron microscopy images show that Mg–Al LDH films are fabricated in situ. After calcination at 500 °C for 4 h, Mg–Al mixed metal oxide (MMO) films that inherited the microstructure of LDH precursor films are obtained. The surface concentration of nano-MgO dispersed in the MMO matrix and the microstructure of the films may be tailored by varying the crystallization time of LDH precursor films. The superhydrophilic property of MMO films arising from their microstructure can reduce the adsorption and adhesion of bacteria and retard biofilm formation. Moreover, nano-MgO dispersed in the MMO matrix has high bactericidal activity against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Vibrio fischeri. Mg–Al MMO films obtained in the present work have excellent antibacterial activities that are due to synergistic effects and thus have potentially applications in antibacterial coatings.