Nanomaterial degrades organic pollutants when activated by light

FAPESP Innovative R&D* – Inappropriate disposal of pesticides and pharmaceuticals has become one of the main sources of environmental pollution in recent decades. Conventional water and effluent treatment is inefficient in degrading these emerging contaminants, which therefore represent a potential public health hazard as well as a threat to the environment.

Different research groups have found semiconductor nanotechnology to offer efficient and sustainable processes for the environmental remediation of these pollutants. Nanostructured semiconductors can be activated by light to trigger a series of physicochemical processes that result in the production of reactive species capable of oxidizing pollutants in the reaction medium.

This approach was explored in a study recently reported in an article published in the Journal of Environmental Chemical Engineering. The study was conducted by scientists affiliated with the Center for Development of Functional Materials (CDMF) at the Federal University of São Carlos (UFSCar) in São Paulo State, Brazil.

The researchers analyzed the photocatalytic properties of titanium dioxide (TiO₂) doped with boron or nitrogen by polymeric precursor, microwave-assisted hydrothermal and sonochemical synthesis to obtain hydroxyl radicals that efficiently oxidized organic pollutants.

The results of the analysis showed that the boron-doped nanomaterials synthesized by the microwave-assisted hydrothermal method were highly efficient for producing hydroxyl radicals under ultraviolet (UV) or visible light.

“The article discusses in detail the influence of the different processes on the degradation of fluoxetine, which is classified as an emerging contaminant and has been found in surface water in various parts of the world,” said Ailton Moreira, first author of the article and a researcher at CDMF, a Research, Innovation and Dissemination Center (RIDC) funded by FAPESP and hosted by UFSCar.

Research groups at UFSCar, the University of São Paulo (USP), the Federal University of Alfenas (UNIFAL) and the Federal University of Lavras (UFLA) also participated in the study.

The article “Photoactivity of boron-or nitrogen-modified TiO2 for organic pollutants degradation: Unveiling the photocatalytic mechanisms and by-products" is at: www.sciencedirect.com/science/article/abs/pii/S2213343722020802?via%3Dihub.

* With information from CDMF.