<p>In this work, FeS was anchored on mesoporous silica microspheres (SiO₂200, SiO₂500, and SiO₂1000), and named as FeS@SiO₂ (i.e., FeS@SiO₂200, FeS@SiO₂500, FeS@SiO₂1000), in adsorbing and detoxifying U(VI)/Cr(VI) from wastewater. Results demonstrated that FeS@SiO₂ exhibited higher efficiency towards U(VI)/Cr(VI), outperforming FeS and SiO₂ alone. Kinetic investigations revealed that adsorption of U(VI)/Cr(VI) followed pseudo–second–order model best, highlighting effective chemical interplay. XPS investigations demonstrated multi–species which was included FeS, Fe(II), S²⁻ and polysulfide (S₂²⁻, S_n²⁻) could be employed as reductants for U(VI)/Cr(VI) adsorption. The combination of SiO₂ and FeS offered an enhanced efficiency for U(VI)/Cr(VI), making these composites promising materials in water purification.</p> Graphical Abstract <p></p>