Synthesis and application of titanium dioxide photocatalysis for energy, decontamination and viral disinfection: a review

International audienceGlobal pollution is calling for advanced methods to remove contaminants from water and wastewater, such as TiO2-assisted photocatalysis. The environmental applications of titanium dioxide have started after the initial TiO2 application for water splitting by Fujishima and Honda in 1972. TiO2 is now used for self-cleaning surfaces, air and water purification systems, microbial inactivation and selective organic conversion. The synthesis of titanium dioxide nanomaterials with high photo-catalytic activity is actually a major challenge. Here we review titanium dioxide photocatalysis with focus on mechanims, synthesis, and applications. Synthetic methods include sol-gel, sonochemical, microwave, oxidation, deposition, hydro/sol-vothermal, and biological techniques. Applications comprise the production of energy, petroleum recovery, and the removal of microplastics, pharmaceuticals, metals, dyes, pesticides, and of viruses such as the severe acute respiratory syndrome coronavirus 2

Synthesis and application of titanium dioxide photocatalysis for energy, decontamination and viral disinfection: a review

International audienceGlobal pollution is calling for advanced methods to remove contaminants from water and wastewater, such as TiO2-assisted photocatalysis. The environmental applications of titanium dioxide have started after the initial TiO2 application for water splitting by Fujishima and Honda in 1972. TiO2 is now used for self-cleaning surfaces, air and water purification systems, microbial inactivation and selective organic conversion. The synthesis of titanium dioxide nanomaterials with high photo-catalytic activity is actually a major challenge. Here we review titanium dioxide photocatalysis with focus on mechanims, synthesis, and applications. Synthetic methods include sol-gel, sonochemical, microwave, oxidation, deposition, hydro/sol-vothermal, and biological techniques. Applications comprise the production of energy, petroleum recovery, and the removal of microplastics, pharmaceuticals, metals, dyes, pesticides, and of viruses such as the severe acute respiratory syndrome coronavirus 2

The ozone-activated peroxymonosulfate process (O3/PMS) for removal of trace organic contaminants in natural and wastewater : effect of the (in)organic matrix composition

The ozone-activated peroxymonosulfate process (O3/PMS) is an emerging advanced oxidation process for the removal of trace organic contaminants (TrOCs) in water, because it produces both hydroxyl and sulfate radicals. Its potential has been shown in distilled water, but limited research has been performed in real (waste)waters. Therefore, this work focuses on the added value of PMS in ozonation and on fundamental aspects of the process in three different types of water, i.e. secondary effluent, surface water and groundwater. The instantaneous ozone demand (IOD) of the different waters, representing the ozone decomposition by highly ozone reactive species, increased by adding PMS. This effect is more pronounced in surface water and groundwater than in secondary effluent, which indicates more reaction between O3 and PMS and thus a higher potential for radical production in less loaded matrices. This is also reflected in the (increased) removal of atrazine (ATZ) and chloramphenicol (CHLOR) when applying the O3/PMS process. Compared to ozonation, the removal efficiency obtained with O3/PMS was 12% higher in secondary effluent, while this was up to 35% and 43% higher in respectively surface water and groundwater. Scavenging experiments and removal of p-nitrobenzoic acid (pNBA), an ?OH probe, showed that hydroxyl radicals rather than sulfate radicals are the main species contributing for > 60% to O3/PMS induced TrOC removal in natural and wastewaters. Next to the bulk organic matter, chloride proved to be a crucial matrix constituent that might be responsible for the conversion of sulfate into hydroxyl radicals