Fabrication of graphitic carbon nitride and black phosphorene composite based electrochemical sensor and application for sensitive determination of quercetin

A novel electrochemical method for sensitive detection quercetin (QU) was constructed with graphitic carbon nitride (g-C 3 N 4 ) and black phosphorene (BP) composite (g-C 3 N 4 @BP) modified carbon ionic liquid electrode (CILE) as signal amplified interface. g-C 3 N 4 @BP was synthesized by a hydrothermal method with the characteristics investigated by SEM, XPS, FT-IR, XRD and electrochemical methods. Electrochemical behaviors of QU on the modified electrode (g-C 3 N 4 @BP/CILE) was investigated with the electrochemical parameters calculated and the experimental conditions optimized. The excellent electroanalytical result of QU was realized with the linear concentration range from 5.0 nmol/L to 90.0 µmol/L and a lower detection limit of 1.7 nmol/L (3σ). It was proved that the composite exhibited the synergistic effect of BP and g-C 3 N 4 with more active sites, porous structure, large specific surface area, good electrical conductivity and strong electrocatalytic activity. The g-C 3 N 4 @BP/CILE was successfully used to detect the practical drug and food samples with satisfactory recoveries.