Search

[Display omitted] • Defective MoS 2 enhanced PCA removal of Fe3+/PS system compared with pristine MoS 2. • S defects in MoS 2 facilitated the cycle of Fe3+/Fe2+ to enhance PCA degradation. • S defects in MoS 2 increased the electron density around Mo. • S defects in MoS 2 enhanced the adsorption of Fe3+. Advanced oxidation processes (AOPs) based on persulfate (PS) has attracted great attention because of its outstanding performance for decomposing chlorinated aromatic hydrocarbons in wastewater. While Fe-based materials can effectively activate PS and are environment-friendly, the low stability of Fe2+ and little activation capability of Fe3+ limit the broad applications of Fe2+ (or Fe3+) activated PS system in practical applications. In this work, taking molybdenum disulfide (MoS 2) as the co-catalyst in Fe3+/PS system, we report a strongly enhanced persulfate activation efficiency of Fe3+/PS system by engineering S defects in MoS 2. The combination of experiments and density functional theory (DFT) calculation demonstrate that S defects in MoS 2 modify the surface charge distribution, leading to the formation of an electron deficient center near S defect and increasing the electron density near Mo site. As a result, more Fe3+ in Fe3+/PS system is reduced into Fe2+ by MoS 2 with S defects, resulting in more reactive oxygen species generated. Furthermore, S defects promote the adsorption of Fe3+ on the MoS 2 surface, which further enhance the activating performance for PS through promoting to form cycle of Fe3+/Fe2+. This work provides a new strategy for improving co-catalytic properties of MoS 2 and expands the application of Fe3+/PS system for contaminants remediation. [ABSTRACT FROM AUTHOR]