Catalytic reduction of methyl orange by Ag/SrFe2O4 nanocomposite prepared using celestine and Marrubium vulgare L. leaf extract.

In this study, the celestine (natural strontium sulfate) is first converted to strontium carbonate (SrCO₃). Then, magnetic strontium ferrite nanocomposite was produced from the reaction of obtained SrCO₃ (in HNO₃) and Fe(NO₃)₃ solution. Biosynthesized Ag nanoparticles (NPs) supported on SrFe₂O₄ were prepared by the aqueous horehound (Marrubium vulgare L.) leaf extract. The synthesized nanocomposites were analyzed using different characterization techniques, including Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), field emission scanning electron microscope (FESEM), and X-ray spectroscopy (EDX). The FESEM analysis of Ag/SrFe₂O₄ nanocomposite confirms the formation of spherical Ag NPs dispersed on the surface of strontium ferrite with an average particle size below 50 nm. The reduction/decolorization time of 10 ppm methyl orange (MO) solution in the presence of 10.6 × 10⁻³ M sodium borohydride (NaBH₄) solution and 9 mg of Ag/SrFe₂O₄ catalyst with good activity and reusability was 2.5 min. [ABSTRACT FROM AUTHOR]