Highly efficient PMS activation by synergistic effects of FeS₂/CoS₂ for rapid diuron degradation: Advanced oxidation...

Diuron is an organic pollutant (herbicide). For the first time, a solvothermal method was used to prepare FeS₂/CoS₂ catalysts to activate peroxymonosulfate (PMS) for the degradation of diuron. The material characteristics of FeS₂/CoS₂-3 before and after use were analyzed. The study tested the impact of various factors on the degradation efficiency of diuron in solution. The electron transport phenomenon between FeS₂ and CoS₂ enhanced the activation efficiency of PMS and increased the degradation rate of diuron. After 8 h of dynamic cycling, FeS₂/CoS₂-3 could still activate PMS to efficiently degrade diuron. Singlet oxygen (¹O₂) plays an important role in the degradation of diuron in the presence of hydroxyl radical (OH•), sulfate radical (SO₄•^-), superoxide radical (O₂•^-), and high-valent metals. FeS₂/CoS₂-3 also effectively degraded methylene blue, neutral red, and sulfamethoxazole, and its degradation of diuron in various environments remained effective. The electrostatic potential, molecular bond energy, and frontier molecular orbitals of the diuron molecule were studied for the first time. A variety of potential degradation pathways for diuron were investigated, and the biotoxicity of the resulting intermediates was simulated and assessed. In addition, the primary mechanism by which FeS₂/CoS₂-3 activates PMS to degrade diuron has been proposed.