Facile synthesis of nitrogen doped carbon dots from waste biomass: Potential optical and biomedical applications

Abstract

Abstract We report a facile, one-pot hydrothermal synthesis of surface passivated, nitrogen doped carbon dots (N-CDs) from jackfruit peel and tamarind peel precursors. The synthesized N-CDs emit strong excitation dependent fluorescence in the blue region. The samples illustrate exciting quantum confined optical properties. Graphitization of N-CDs is identified by X-ray diffraction. Surface functionalization is confirmed by FT-IR studies whereas nitrogen doping by X-ray photoelectron spectroscopy. The average size of synthesized N-CDs estimated from transmission electron images is 6.4 nm and 5.3 nm for jackfruit peel and tamarind peel precursors respectively. Quantum yield of N-CDs from jackfruit peel (13.04%) is higher than that from tamarind peel (6.13%). Appreciable anti-cancerous activity of the as-prepared carbon dots could be detected with DLA tumour cells extracted from mice. The work proposes an innovative design to yield blue luminescent carbon dots with high quantum yield from biowaste, providing a green and sustainable alternative to traditional carbon sources.