Interplay between piezoelectric and co-catalytic effect of Fe3O4@MoS2 synergistically enhances Fenton-like reaction

Abstract

Fenton-like reaction based on peroxymonosulfate (PMS) activation represents a promising approach for water purification. However, its practical application is often hindered by the inadequate redox cycling of catalytic metal sites. To address this challenge, we propose an effective strategy that integrates piezoelectric and co-catalytic effects into PMS activation. Specifically, we designed a series of MoS₂ and Fe₃O₄ composites (denoted as Fe₃O₄@MoS₂-X, where X represents the Fe/Mo molar ratio). Among these, Fe₃O₄@MoS₂-0.5 demonstrated optimal performance in a piezoelectric-enhanced Fenton-like coupling system (catalyst/PMS/US), with the conventional Fenton-like system (catalyst/PMS) serving as a control. The Fe₃O₄@MoS₂-0.5/PMS/US system exhibited significantly enhanced pollutant degradation kinetics (k_obs = 1.04 min⁻¹), outperforming the Fe₃O₄@MoS₂-0.5/PMS system (k_obs = 0.22 min⁻¹). This improvement is attributed to the synergistic interplay between piezoelectricity and co-catalysis, which facilitated efficient electron supply and transfer, thereby accelerating the redox cycling of Fe³⁺/Fe²⁺ pairs. By leveraging dual reaction pathways—radical and non-radical mechanisms—the coupling system demonstrated exceptional interference immunity and achieved superior degradation efficiencies across a wide range of solution pH and complex water matrices. This study introduces an innovative and effective strategy to enhance the performance of conventional Fenton-like reaction, offering valuable insights for the development of advanced water treatment technologies.