Metal-free modification of porphyrin-based porous organic polymers for effective photocatalytic degradation of bisphenol A in water

Porphyrin based photocatalysts have demonstrated exciting features, such as outstanding photoelectric properties, good photothermal stability, and structural diversity. Meanwhile, hydrophilic porphyrin is easily dispersed in water, increasing photocatalyst contact with pollution while also reducing the distance of carrier transport. In this study, porphyrin-based porous organic polymers (POPs), TEPP-F-TBT, was successfully fabricated for degradation of bisphenol A (BPA) using Sonogashira coupling. To enhance the dispersion of TEPP-F-TBT, modification of TEPP-F-TBT by 3-mercapto-1-propanesulfonic acid sodium was performed using the thiol-alkyne click reaction. Subsequently, under illumination, the modified polymer TEPP-F-TBT-S degrades more than 99.0% of 10 ppm BPA within 30 min, but TEPP-F-TBT can only degrade 25% of 10 ppm BPA under the same conditions. A possible mechanism of photocatalytic degradation of BPA was speculated using characterizations, such as electron spin resonance and trapping experiments. Our study presents a green approach for modifying POPs to design and synthesize organic photocatalysts with outstanding performance.