Synthesis of g-C3N4/Fe3O4 nanocomposites and application as a new sorbent for solid phase extraction of polycyclic aromatic hydrocarbons in water samples

An easy preparation of g-C 3 N 4 /Fe 3 O 4 nanocomposites by chemical co-precipitation has been demonstrated. The as-prepared materials were characterized by X-ray diffraction, transmission electron microscopy , Fourier transform infrared spectroscopy and thermogravimetric analysis . The high affinity of g-C 3 N 4 toward polycyclic aromatic hydrocarbons and the magnetic behavior of Fe 3 O 4 were combined to provide an efficient and simple magnetic solid phase extraction (MSPE). The adsorption and desorption of polycyclic aromatic hydrocarbons on g-C 3 N 4 /Fe 3 O 4 were examined. Different factors affecting the magnetic solid phase extraction of polycyclic aromatic hydrocarbons were assessed in terms of adsorption, desorption, and recovery. Under the optimized conditions, the proposed method showed good limits of detection (LOD, S/N=3) in the range of 0.05–0.1   ng   mL −1 and precision in the range of 1.8–5.3% (RSDs, n =3). This method was also successfully applied to the analysis of real water samples; good spiked recoveries over the range of 80.0–99.8% were obtained.