Utilizing Self‐Floating Cu3BiS3 Polydopamine Polyurethane Sponges for Enhanced Water Purification: Harnessing the free radical and non‐radical in persulfate system

Abstract The advanced oxidation process based on persulfate group is a promising technology for water purification. However, the synergistic effect of free radical and non‐free radical degradation is still not feasible in the persulfate activation process, which consumes a large amount of external energy. The self‐floating Cu 3 BiS 3 /polydopamine/polyurethane sponge was prepared using a simple method, resulting in high catalytic performance when activated by peroxydisulfate (PDS). The experiments conducted to identify free radicals showed that the degradation process of tetracycline (TC) involved the synergistic action of non‐radical 1 O 2 and free radicals (SO 4 ⋅ − and • OH) and the conversion of Cu + /Cu 2+ . The addition of Cl − , HCO 3 − , PO 4 3− , and SO 4 2− to the solution did not significantly affect the high degradation rate of TC. Furthermore, the interfacial evaporation process achieved a remarkable evaporation rate of 1.53 kg m −2 h −1 and produced reclaimed water without any detectable TC contaminants. The sponge also exhibited excellent salt resistance and chemical stability. This study provides valuable insights into the degradation of antibiotics and the desalination of seawater.