Dr. Dionysios (Dion) D. Dionysiou is currently a Professor of Environmental Engineering and Science Program at the University of Cincinnati. He teaches courses and performs research in the areas of drinking water quality and treatment, advanced unit operations for water treatment, advanced oxidation technologies and nanotechnologies, and physical-chemical processes for water quality control. He has received funding from NSF, US EPA, NASA, NOAA/CICEET, USGS, USDA, Ohio Sea Grant, USAID, and DuPont. He is currently one of the editors of Chemical Engineering Journal, Editor-in-Chief of the Journal of Advanced Oxidation Technologies, and Editor-in-Chief of the Journal of Environmental Engineering (ASCE). He is a member of the Editorial Boards of several other journals. Dr. Dionysiou is the author or co- author of over 325 refereed journal publications, over 86 conference proceedings, 32 book chapter publications, 26 editorials, and more than 600 presentations. He has edited/co-edited 6 books on water quality, water reuse, ferrates, and photocatalysis. He is currently co-editing a book on harmful algal blooms. Dr. Dionysiou’s work received over 15,000 citations with an H factor of 68.
In this study, a facile approach was successfully employed to improve the photocatalytic activity of Bi2WO6. The pristine Bi2WO6 (p-Bi2WO6) nanoplates were prepared through a conventional hydrothermal method and then were subjected to sodium hydroxide aqueous solutions with concentrations ranging from 0.5 M to 10 M. Under visible light irradiation, the photocatalytic activities of base-modified Bi2WO6 (b-Bi2WO6) were significantly enhanced when compared to that of the p-Bi2WO6. However, as the concentration of base solution continues to increase, the performance of b-Bi2WO6 deteriorated. The b-Bi2WO6 nanoplates were characterized by various techniques including XRD, TEM, porosimetry analysis, UV–vis spectrometry, and XPS. The results indicated that the surface of b-Bi2WO6 was etched by alkaline solutions, which improved the surface area and produced active sites on the surface. The b-Bi2WO6 nanoplates were proved to be highly effective in photocatalytic degradation of emerging contaminants including ibuprofen (IBP) and microcystin-LR (MC-LR). The degradation byproducts and pathways of IBP were also investigated.
This study is beneficial to further understand the chemistry and properties of Bi2WO6 materials. The facile modification proposed here provides a novel strategy for improving the photocatalytic activity of Bi2WO6 materials, which could also be applied to other types of photocatalysts. In addition, the efficient degradation of IBP and MC-LR under visible light demonstrates the great potential of environmental remediation using sustainable solar energy.