Construction of novel Ag/HKUST-1/g-C 3 N 4 towards enhanced photocatalytic activity for the degradation of pollutants under visible light.

A novel Ag/metal-organic framework/graphitic carbon nitride (Ag/HKUST-1/g-C 3 N 4 , AHC) photocatalyst was prepared via an in situ growth strategy and photo-deposition technique for environmental remediation. The as-obtained samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), N 2 adsorption-desorption isotherm measurement, UV-vis diffuse reflection spectroscopy (UV-vis DRS), and photoluminescence (PL) spectroscopy. The results indicated that the hybrids have large surface area, mesoporous structure and enhanced visible-light absorption. The as-prepared hybrid samples exhibited considerable improvement in photocatalytic activity and stability for rhodamine B (RhB) degradation under visible light irradiation ( λ > 420 nm). In addition, they also have good adsorption properties. Compared to the pure g-C 3 N 4 and Ag/g-C 3 N 4 , the 5% AHC photocatalyst showed superior photocatalytic activity. Moreover, 5% AHC exhibits good photocatalytic activity even after four cycles. Additionally, the active species trapping and electron spin resonance (ESR) experiments indicated that h + and ·OH were the main active species.