Ultrafast activation efficiency of three peroxides by Fe₇₈Si₉B₁₃ metallic glass under photo-enhanced catalytic oxidation: A comparative study

Metallic glasses with long-range disordered atomic structure have recently been attracted a great deal of research attention in catalytic field. Compared to crystalline materials, the metallic glasses present many advanced catalytic properties, yet the catalytic mechanism is not sufficiently understood. In this work, an Fe₇₈Si₉B₁₃ glassy ribbon manufactured by melt-spinning method was applied for the first time to compare its activation behavior on three peroxides, including hydrogen peroxide (H₂O₂), persulfate (PS) and peroxymonosulfate (PMS). It was shown that Fe₇₈Si₉B₁₃ metallic glass had exceptionally high capability for activating these three common peroxides to produce reactive radicals ([rad]OH and/or SO₄•⁻). The dominant species of H₂O₂ in this work was demonstrated as hydroxyl radical ([rad]OH) while the PS and PMS activation mainly generated sulfate radical (SO₄•⁻). The order of predominant radical generation rate by Fe₇₈Si₉B₁₃ activation under UV−vis irradiation was PS > H₂O₂ > PMS. The relative contribution of sulfate radical (SO₄•⁻) in PS activation was 78% compared to 61% in PMS. All the peroxides activated by Fe₇₈Si₉B₁₃ metallic glass presented a radical generation rate at least ∼2 times higher than other iron-containing materials. Crystal violet (CV) dye was used to investigate the catalytic performance of Fe₇₈Si₉B₁₃ metallic glass for peroxides, which showed an ultrafast dye degradation rate with completely color removal within 15 min. The radical evolution mechanisms for H₂O₂, PS and PMS activation were also investigated. The change in surface morphology of ribbon after 5th run reused indicated that the inclusions of Si leading to formation of SiO₂ layer played an important role in the surface stability of ribbons.