Nitrogen-doped luminescent carbon nanodots for optimal photo-generation of hydroxyl radicals and visible-light expanded photo-catalysis

Luminescent carbon nanodots (CNDs) have been obtained by hydrothermal processing of ascorbic acid (AA) and ethanolamine (EN). The resulting N-doped carbon nanostructures exhibit interesting and tunable emission capabilities with a dual behavior as down-converters and more importantly, as up-converting quantum dots. Herein, we also evaluate the optical response of these CNDs to selectively generate highly reactive oxidative hydroxyls (OH) upon irradiation with different light-emitting diodes (LEDs) in the visible–NIR range. Finally, the role of the N-doped CNDs as nano-sensitizers to maximize the solar light harvesting and expand the photo-catalytic response of a commonly used UV-active catalyst such as TiO2 was successfully tested in the degradation of an organo-chlorinated compound under visible light. [Display omitted] •The hydrothermal processing of ascorbic acid and ethanolamine renders highly fluorescent and stable carbon nanodots.•The synthesized carbon dots exhibit up-converting properties.•Oxidative hydroxyl radicals are generated under the excitation of different LED sources in the whole UV-vis-NIR range.•The CNDs expand the photo-catalytic response of TiO2 in the visible-NIR range.