Shape-control of Zinc Oxide nanoparticles: enhancing photocatalytic activity under UV irradiation

8th International Congress of Engineering Physics

物理学;工业技术

Montero-Muñoz, M.^1 ; Ramos-Ibarra, J.E.^1 ; Rodríguez-Páez, J.E.^3 ; Ramirez, A.^2 ; Huamaní-Coaquira, J.A.^1

Institute of Physics, University of Brasilia, Brasília-DF

70910-900, Brazil^1

Department of Chemistry, University of Cauca, Popayán'Cauca, Colombia^2

Department of Physics, University of Cauca, Popayán-Cauca, Colombia^3

关键词: Controlled precipitation;    Different sizes;    Photocatalytic activities;    Scanning electron microscopy image;    Solid phase evolutions;    UV-Vis absorption spectroscopy;    Washing process;    Zinc oxide (ZnO) nanostructures;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/792/1/012068/pdf
DOI  :  10.1088/1742-6596/792/1/012068

学科分类：工业工程学

来源: IOP

【 摘 要 】

Zinc oxide (ZnO) nanostructures with different sizes and morphologies were synthesized using the Controlled Precipitation Method. It follows a standard process, but with different synthesis and washing solvents to modify the features related to the photocatalytic activity. The solid phase evolution during aging step was followed using Infrared Spectroscopy (FTIR) and the solids obtained, after the washing process, were characterized using X-ray diffraction (XRD). The Rietveld refinement indicates a Wurtzite phase (space group P63mc) as majority phase with lattice parameters a = 3.2530 Å and c = 5.2125 Å. Scanning electron microscopy (SEM) image shows a sponge-like morphology for the sample synthesized with ethylene glycol as solvent, acidified with nitric acid and washed with water. The sample synthesized and washed with water shows a needle-like morphology; and the sample synthesized in acetic acid and washed with water shows particles with undefined morphology. The optical properties of the as-prepared ZnO samples were investigated by UV-vis absorption spectroscopy. Finally, the photocatalytic activity of ZnO powders was studied from the initial rate of decomposition of H2O2in aqueous solution. The best results were obtained with samples synthesized and washed with water; the influence of all the solvents on the morphology of ZnO samples and the effect of the morphologies on the photocatalytic activity are discussed.