Effectiveness of I-doped ZnO as polyvalent material for both anti-bacterial and photocatalytic treatments

Abstract

IxZnO marerials were prepared by an easy microwave post-heating process. I content (x) was taken 0, 0.025, 0.05, 0.075 and 0.1, while the heat treatment was performed at 450 degrees C for 2 h. The structural properties were characterized via XRD, ATR, EDS, XPS and SEM. The optical characterization and the electronic transport were investigated using the diffuse reflectance spectroscopy analysis, the conductivity, and Seebeck coefficient determination against temperature. The antibacterial effect and photocatalytic activity have been established. The results display the generation of a single hexagonal wurtzite phase, whatever the doping level, possess a crystallite size around 20 nm. I-doping induces in one part the alteration of Zn-O-Zn network and, in another part, a partial substitution of oxidic sites. I-doping was confirmed by EDS analysis, and the atoms were dispersed with high uniformity according to the mapping element. XPS analysis also confirmed the surface composition by clearly identifying I-3(-) and I-5(-) ions. The bandgap E-g shift with doping was attributed to the new localized states appearance close to the conduction band. Transport properties were particularly improved for both compositions x = 0.025 and 0.05, which positively impacted the photoactivity against the degradation of 2,4-D herbicide under sunlight. The resolved photocatalytic degradation process was attributed preferentially to O-2(-)degrees,degrees OH and h(+) radical active species. I-doping also improved drastically the bactericidal activity of ZnO on Gram-positive Staphylococcus aureus in 24 h. (C) 2022 Elsevier B.V. All rights reserved.