Coral-like porous tubular Ni doped g-C3N4 nanocomposites as bifunctional templates for photocatalytic degradation and fluorescence detection of sunset yellow in beverages

In this study, novel Ni-doped N-vacancy coral-like porous tubular g-C3N4 (Ni–CN) nanocomposites were fabricated through a simple calcination strategy. The Ni–CN photocatalysts exhibited superior photocatalytic efficacy in the degradation of sunset yellow (SY) when exposed to visible light irradiation. The optimized Ni–CN nanocomposite contributed the highest SY removal efficiency of 96.87% after 120 min of irradiation, showing good reusability and structural stability. The as-prepared Ni–CN gel spheres had a high removal rate of SY from orange juice. In addition, Ni–CN nanosheets (Ni–CN NSs) obtained by ultrasonic stripping can be used as highly selective and sensitive fluorescent sensors for the detection of SY in beverages through dynamic or collisional fluorescence quenching mechanisms. The linear range of Ni–CN NSs for SY detection was 0–80 μM and the detection limit was 0.0397 μM. Here, the constructed Ni–CN nanocomposites provide a novel route for efficient removal and sensitive detection of SY in beverages.