Alkali-assisted synthesis of gourd flesh derived tricolor F/N co-doped carbon dots for efficient degradation of organic dyes

Abstract A novel tricolor F/N co-doped CDs was synthesized by alkali-assisted control with gourd flesh as a precursor, targeting at the catalytic degradation of organic dyes with extremely high catalysis rate. The synthesized nanomaterials were characterized by X-ray diffraction, Transmission electron microscopy, Fourier transform infrared spectra and X-ray photoelectron spectroscopy techniques, indicating that the tricolor F/N-CDs have good dispersion and abundant surface defects which were gradually increasing from F/N-G-CDs, F/N-Y-CDs to F/N-O-CDs. Through the UV–visible and fluorescence spectra, the tricolor F/N-CDs all exhibited good fluorescence performance and the fluorescence lifetime was nano-scale level. The tricolor F/N-CDs displayed excellent photocatalytic activity which was evaluated by the organic dyes methylene blue (MB) and congo red (CR) as models. The important thing is that under sunlight irradiation, the degradation efficiency of using tricolor F/N-CDs for MB reaches ~100% and the degradation efficiency for CR dye reaches ~98% in a pole short time. With the red shift of the fluorescent tricolor F/N-CDs, the degradation time gradually decreased and the degradation rate gradually increased. The results explained that the prepared tricolor F/N-CDs had excellent application prospects in the natural degradation.