Investigation of the efficiency of several TiO2 microstructures for the photocatalytic degradation of nanoplastics.

Nanoplastics in the environment are becoming one of the critical issues of our time, with widespread and harmful impacts on global aquatic ecosystems. These plastic fragments, smaller than 1 μm, originate from multiple sources, including improper disposal of plastic waste and spoilage of synthetic materials. Their pervasive presence in aquatic environments, coupled with their persistence and bioaccumulation ability poses significant risks to human health and the marine ecosystem. Increasing recognition of the widespread of nanoplastics and their harmful effects has prompted the search for innovative solutions to address this particular pollution. Among the various proposed methods, photocatalysis emerges as a promising option for the degradation of nanoplastics, exploiting the ability of photocatalysts to activate advanced oxidation reactions under sunlight irradiation. However, the need for highly selective and efficient photocatalysts remains a critical challenge in converting this technology into practical solutions. In this context, we investigated the efficiency of several TiO2 microstructures for the photocatalytic degradation of nanoplastics. Our methodology focuses on the controlled hydrothermal synthesis on TiO2 in 5M, 6M, and 7M HCl to obtain at least three different microstructures able to degrade nanoplastics. The results showed that performing the hydrothermal synthesis at 150°C and different HCl concentrations led to three different microstructures, such as two types of spheres and nanoflowers. All microstructures are composed of rutile TiO2 and present different surface area values, which correlate with their differences in the efficiency of the nanoplastics photocatalytic processes. The results of this work show that photocatalysis can significantly contribute to solving environmental challenges related to nanoplastic pollution. In the future, this approach will be optimized to capture the CO2 produced from nanoplastics mineralization and to avoid producing organics with equal or more significant environmental impact than nanoplastics originally found in aquatic environments. Also see: https://micro2024.sciencesconf.org/558477/document