Investigation of bi-layered ZnO-Ni photocatalyst powder produced by reactive magnetron sputtering technique

Abstract

The goal of the current study was to produce magnetic photocatalyst powder consisting of bi-layered ZnO-Ni particles for easy manipulation and collection during the repetitive photocatalytic water treatments. First, magnetron sputtering was used to cover NaCl grains by Ni underlayer and ZnO overlayer. Then the salt was washed off with distilled water. SEM, EDS and XRD analysis confirmed that obtained particles can be characterized as bi-layered open shells with nanocrystalline ZnO phase on one side and metallic Ni on the other side. In laboratory tests larger part of initial bi-layered powder were successfully recollected by magnets even after 10 consecutive usage cycles. Measurements of photocatalytic performance demonstrated relatively high activity and stability of bi-layered ZnO-Ni powder. Photocatalytic treatment of S. Typhimurium bacteria with ZnO-Ni powder and UV light in 1 hour reduced S. Typhimurium viability by more than 98 %, but similar treatment using visible light was not efficient.