Engineering phase and vacancy with anchoring Fe nanoparticles for photothermal conversion in peroxymonosulfate activation toward efficient removal of carbamazepine

The peroxymonosulfate (PMS) based advanced oxidation processes had demonstrated great potential in water remediation, but the shortage of PMS active sites in the catalyst and the low conversion of active sites limited the wide application in practice. As a result, the design and synthesis of efficient and environmentally friendly catalysts for the activation of PMS had garnered significant attention. Thus, we enhanced electron transfer efficiency by introducing the metallic 1T phase into 2H phase molybdenum disulfide (THMS) and increased the active sites through the introduction of sulfur defects using the Joule heating strategy, resulting in the formation of defect-rich THMS (DTHMS). In addition, we anchored Fe nanoparticles (DTHMS@Fe) that could give rise to coupled photothermal and plasmon resonance effects under simulated sunlight irradiation to promote the activation of PMS and the dissociation of H2O, resulting in an augmented production of radicals. In the optimized DTHMS@Fe hybrid, an impressive degradation rate of Carbamazepine (CBZ) approached 99% within 15 min. The temperature of the DTHMS@Fe/PMS/light system was increased to 49 °C with irradiation for 10 min and the corresponding apparent rate reaches 0.35695 min−1 which was 8.9 and 5.7 times that of initial THMS (0.0398 min−1) and DTHMS (0.0622 min−1), respectively. Our work offered an innovative solution for constructing PMS co-activated systems by coupling solar photothermal conversion, enabling efficient degradation of organic pollutants while reducing costs and energy consumption.