A novel photocatalytic membrane decorated with PDA/RGO/Ag3PO4 for catalytic dye decomposition

In this study, a reduced graphene oxide/silver phosphate (RGO/Ag 3 PO 4 ) was obtained via polydopamine (PDA) modification, and the PDA/RGO/Ag 3 PO 4 composite was coated on the pure polyvinylidene fluoride (PVDF) membrane, which named PDA/RGO/Ag 3 PO 4 /PVDF memebrane. The PDA/RGO/Ag 3 PO 4 was characterized by Fourier transform infrared (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Futhermore, the SEM, Energy dispersive spectrometer (EDS) spectrograms and Atomic force microscopy (AFM) were used to characterize the morphology structure, elemental mapping and roughness of PDA/RGO/Ag 3 PO 4 /PVDF memebrane. The results showed that the composite membrane has a good effect on the degradation of dyes, and the rejection rate of MB reached 99% with an increasing of the composite material ratio. The hydrophilicity of the membrane surface increased by measuring the contact angle, with decrease to 59.2°compared with 88.2°of pure PVDF membrane. In addition, under the visible light irrradiation, the coated membrane still keeps stable flux and high separation efficiency after 5 cycles. Hence, this study provides an attractive PVDF modified membrane.