The invention belongs to the technical field of environment functional materials and relates to a preparation method and application of a C3N4 composite
catalytic membrane. The preparation method comprises the following steps: firstly, dissolving AgNO3 and g-C3N4 into water to obtain a solution A; dropwise adding a Na3PO4 solution into the solution A, stirring, washing, centrifugally separating and
drying to obtain a binary composite
semiconductor material C3N4@Ag3PO4; secondly, dissolving
dopamine into a
Tris-HCl solution, putting a PVDF membrane into the solution, modifying the
dopamine, depositing a polydopamine layer on the surface of the PVDF membrane, and carrying out
room temperature drying on the obtained polydopamine modification membrane (PDA@PVDF); dissolving the C3N4@Ag3PO4 into the water, and carrying out
ultrasonic dispersion to obtain C3N4@Ag3PO4 suspension; taking PDA@PVDF as a base membrane, and carrying out vacuum
filtration and
room temperature drying. A
silver phosphate nanomaterial is loaded with a
graphite nitrogen carbide nano-sheet to form point-surface contact, so that compounding of C3N4 photo-induced
electron hole pairs is inhibited, the stability of Ag3PO4 is improved and further the photocatalytic activity is improved; the C3N4@Ag3PO4 is loaded on the PVDF membrane, so that the problems that catalyst
powder is difficult to recover and easy to waste,and membrane holes are blocked because of membrane
pollution are solved; the removal rate of pollutants is improved.