Graphitic carbon nitride nanosheets (g-C3N4 NS) as dual responsive template for fluorescent sensing as well as degradation of food colorants

In this work, fluorescent g-C₃N₄ NS with laminar morphology and ultrathin thickness were fabricated. The as synthesized NS were well characterized by UV–Visible and Fluorescence spectroscopy, FT-IR, XRD and HR-TEM. The bright blue fluorescent suspension of g-C₃N₄ NS was utilized for efficient detection of food colorant; tartrazine (Tz) and sunset yellow (SY). Both food colorant were able to quench fluorescence of NS efficiently were able to detect them selectively over other interfering analytes. The chemosensor showed linear range response for low concentration of Tz and SY with limit of detection for Tz and SY as 0.0325 μM (32.5 nM) and 0.221 μM (221 nM), respectively. They served as non-toxic and low cost photocatalyst. The catalytic degradation process was confirmed by mass and UV–Visible spectra analysis. The g-C₃N₄ NS served dual role of detection as well as photocatalytic degradation of food colorant.