Boosting photocatalytic activity for porphyrin-based D-A conjugated polymers via dual metallic sites regulation

The incorporation of metallic sites into polymer photocatalysts has been a successful strategy to realize high photocatalytic activities. Herein, a series of bimetallic porphyrin-based D-A conjugated polymers M1TAPP-M2Bpy (M1, M2 =H2, Zn, Cu) were prepared through dual metallic sites regulation for enhanced photocatalytic degradation of bisphenol A (BPA) and benzene series pollutants. The n-conjugated polymer skeleton facilitates the adsorption of aromatic pollutants. Superior to monometallic sites, the intrinsic charge transfer characteristics of both porphyrin and bipyridine moieties can be modulated by dual metallic sites, promoting the dissociation of charge carriers. The highly-dispersed metallic reactive sites further boost the photocatalytic activities. Owing to optimized dissociation of electron-hole pairs, CuTAPP-CuBpy exhibits an outstanding photocatalytic oxidation activity for degradation of 50 ppm BPA completely in only 20 min with a relatively fast rate constant of k = 0.183 min(-1). Dual metallic sites regulation highlighted in this work paves a way toward efficient polymer-based photocatalyst.