Development, dilemma and potential strategies for the application of nanocatalysts in wastewater catalytic ozonation: A review

With the continuous development of nanomaterials in recent years, the application of nanocatalysts in catalytic ozone oxidation has attracted more and more researchers' attention due to their excellent catalytic properties. In this review, we systematically summarized the current research status of nanocatalysts mainly involving material categories, mechanisms and catalytic efficiency. Based on summary and analysis, we found most of the reported nanocatalysts were in the stage of laboratory research, which was caused by the nanocatalysts defects such as easy aggregation, difficult separation, and easy leakage. These defects might result in severe resource waste, economic loss and potentially adverse effects imposed on the ecosystem and human health. Aiming at solving these defects, we further analyzed the reasons and the existing reports, and revealed that coupling nano-catalyst and membrane, supported nanocatalysts and magnetic nanocatalysts had promising potential in solving these problems and promoting the actual application of nanocatalysts in wastewater treatment. Furthermore, the advantages, shortages and our perspectives of these methods are summarized and discussed.