This invention provides an Ag-doped photocatalytic
composite membrane, its preparation method, and its application, relating to the field of
water treatment membrane technology. The Ag-doped photocatalytic
composite membrane of this invention has a composite functional structure consisting of a
polyester nonwoven fabric support layer, a PVDF base membrane core layer, an Ag-BaTiO3 / ZnIn2S4 piezoelectric-photocatalytic functional layer, and a polydopamine hydrophilic protective layer, arranged sequentially. By constructing an Ag-doped dual piezoelectric coupled
heterojunction system, introducing the
surface plasmon resonance effect of Ag ions, and combining
plasma-assisted deposition technology with the composite functional structure, this invention achieves a wide
spectral response (UV to near-
infrared), highly efficient piezoelectric-photocatalytic synergistic degradation, robust catalyst adhesion to prevent detachment, and multiple effects of "separation-degradation-self-cleaning." This solves the problems of traditional piezoelectric-photocatalytic membranes in terms of
catalytic efficiency, long-term stability, and industrial adaptability, and has good application prospects.