Preparation of CuSe-PDA/g-C3N4 and its visible-light photocatalytic performance to dye degradation

CuSe as an excellent photocatalytic semiconductor material has wildly used in the field of photocatalysis. In this paper, CuSe-PDA/g-C 3 N 4 was designed and synthesized, and the photocatalytic performance of CuSe was further enhanced by the addition of polydopamine (PDA) and graphite phase carbon nitride (g-C 3 N 4 ). The as-prepared CuSe-PDA/g-C 3 N 4 was characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), and elemental mapping. The specific surface area and porous characteristics of the material were also studied by N 2 adsorption-desorption isotherm, which the specific surface area were 186.6 m 2 /g and pore size were of 3.1 nm by BET data analysis. The photocatalytic conditions for the degradation of methylene blue (MB) by CuSe-PDA/g-C 3 N 4 were optimized in the experiment. The results showed that the photocatalytic performance of CuSe-PDA/g-C 3 N 4 under visible-light illumination were better than CuSe and PDA owing to the narrow band gap energy and delayed electron-hole recombination. Under the optimized conditions, the removal rate reach to 99% of 50 mg/L MB within 60 min irradiation time. Moreover, the MB removal rate was over 90% through six repeated experiments, which proved that the CuSe-PDA/g-C 3 N 4 composite nanomaterials have good stability and reusability.