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Two novel, multifunctional Fe-based amorphous alloys with the nominal components of Fe78Si9B13 and Fe73.5Si13.5B9Cu1Nb3 exhibit advanced catalytic capability when degrading methyl blue (MB) and methyl orange (MO) dyes. The production rate of hydroxyl radicals ( OH) in this work is 5–10 times faster than other Fe-based catalysts. The surface aging behaviour on Fe78Si9B13 and Fe73.5Si13.5B9Cu1Nb3 ribbons shows a significant effect on the dye degradation efficiency and reusability of the catalyst. Results reveal that crystallized α-Fe, iron oxide and SiO2 are gradually precipitated on the surface of the reused Fe78Si9B13 ribbon which ultimately becomes corroded through with holes. However, the inclusion of Nb atoms in the Fe73.5Si13.5B9Cu1Nb3 alloy causes the formation of niobium oxides which overlay the ribbon surface, and tend to reduce the contact area between the Fe and H2O2, thereby decreasing the generation of OH and further reducing the dye degradation efficiency. Tert-butanol is employed for quenching hydroxyl radicals ( OH), causing a dramatic reduction in the amount available for degrading the MB and MO molecules. The MB and MO dye degradation and mineralization under UV–vis light are also fully investigated. The findings of this critically important work should form the basis of new research opportunities into the study of amorphous alloy catalysis.

The development of new functional applications of amorphous alloy is an active and challenging topic. In this work, amorphous Fe78Si9B13 alloy, a photo-enhanced Fenton-like catalyst, exhibits excellent functional ability in degrading an azo dye. This study reports the dramatic performance gains achieved for photo-enhanced Fenton-like degradation of cibacron brilliant red 3B-A (BR3B-A) dye aqueous solutions, the reusability of amorphous Fe78Si9B13 alloy ribbon catalysts, and the reaction kinetics (k) of the process. The individual and synthetical effects of the various reaction parameters are investigated by employing an orthogonal matrix (L16(45)) experimental methodology. The investigation evaluates the impact of these parameters on the degradation process, in order to demonstrate that UV–vis light could continuously induce hydroxyl radicals ( OH) to be generated in the dye aqueous solution and significantly enhance the rate of dye degradation and mineralization. The experimental results show that nearly 100% color removal is achieved within 5 min under conditions of 2.0 g/L Fe78Si9B13 ribbons, 0.5 M H2O2 and pH 2. UV–vis light intensity ranging from 0 to 7.7 μW/cm2 enhances a dramatic improvement in color removal from 78% at 200 min to 98% at 60 min and an improvement in the reaction kinetics (k) from 0.0413 at 0 μW/cm2 of light irradiation to 0.2901 at 7.7 μW/cm2 of light irradiation under conditions of 2.0 g/L Fe78Si9B13 ribbons, 0.5 M H2O2 and natural pH 6.45. The production of OH is investigated by adding tertiary butanol, resulting in a sharp decrease of dye color removal. Structural characterizations of as-received amorphous Fe78Si9B13 ribbons and of recycled Fe78Si9B13 ribbons are also investigated by transmission electron microscopy (TEM), X-ray diffraction (XRD), UV–vis diffuse reflectance spectrophotometers (UV–vis DRS), scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDS); the results reveal a slight decay of the reused Fe78Si9B13 ribbons, along with a gradual precipitation of crystallized α-Fe, iron oxide and SiO2 on the ribbon surface over the few cycles of usage.