Self-assembled ZnO/Ag hollow spheres for effective photocatalysis and bacteriostasis

Zinc oxide/silver hollow spheres (ZnO/Ag HSs) have been synthesized and employed as both photocatalyst and antimicrobial agent. They possess an efficient photocatalysis to various organic molecular dyes such as methylene blue (MB), methyl orange (MO), phenol red (PhR) and rhodamine 6G (R6G). Among them, the MB reaches the degradation rate of 100% under UV irradiation for 30 min and 58.2% under simulated sunlight for 60 min. A better photocatalytic performance occurs due to their special morphology with hollow spheres, hybrid structure of semiconductor/metal and surface plasmon resonance (SPR) of Ag nanoparticles. In addition, ZnO/Ag HSs exhibit obvious antibacterial effect to Escherichia coli and Staphylococcus aureus based on synergistic bactericidal effect between Ag NP and ZnO. Therefore, the present study offers a promising way to achieve both high efficiency photocatalysis and bacteriostasis based on the hybrid structure of semiconductor/metal.