APPLYING CARBON DOTS: ENHANCEMENT IN WATER OXIDATION SYSTEMS AND IN NANOMEDICINE

Since their first application, nanotechnologies have been capable to produce improvements and revolutionary results in many technological and industrial branches: medicine, transport, food security, environmental management and many others. Among these, nanotechnologies have proved their potential in medicine and in the treatment of polluted water. Nano-medicine made available increasing numbers of personalized and selective diagnostic methods and therapies. Nano-systems produced also more efficient purification processes for the treatment of polluted water. Thanks to the results obtained so far, these research fields are particularly significant and highly valued in the scientific world. With this in mind, the present thesis focused on assessing the application of Carbon Dots (CDs). CDs are nano-sized carbon particles, with dimensions between 1 and 10 nm. Since their discovery, they have proven their potential in countless fields. Here, CDs were evaluated for the treatment of polluted water and for their potential application in nano-medicine. In particular, their reduce toxicity makes them the ideal candidate for drug delivery purposes. In addition to this, their peculiar nature allows their employment as charge delocalizers and photosensitizers, implementing the properties of established water purification systems. Among these systems, TiO2 is, up to now, one of the most powerful material. When excited by the correct wavelength, TiO2 can react with the water absorbed on its surface and produce highly oxidative radicals. Radicals that are capable to decompose water pollutants. In this study, CDs have been synthesized from different precursors, and they have been characterized. The samples with the most promising properties have been selected and applied for the production of a TiO2-based high-performance photocatalytic material, capable of purifying polluted waters by exploiting solar light. This study pointed out how the formation of sub-products during the CDs synthesis may be the responsible for CDs cytotoxicity. The research demonstrated, moreover, that CDs cytotoxicity is not related to the toxicity of the starting reagents. The class of CDs, synthesized with citric acid and diethylenetriamine, displays the best properties for advanced TiO2 oxidation systems and the lowest cytotoxicity. Additionally, a TiO2-based photocatalytic system was also applied for water purification, exploiting the use of solar radiation. A high-performance photocatalytic material was produced by loading the CDs onto TiO2 particles. In order to preserve the CDs properties within the system, a hydrothermal process was developed and evaluated. In conclusion, we obtained a material which may be used to treat polluted water by exploiting the solar radiation. This material may represent the starting point for advanced water purification systems in developed and developing countries.