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Metallic glass, with its unique disordered atomic structure and high density of low‐coordination sites, is regarded as the most competitive new catalyst for environmental catalysis. However, the efficiency and stability of metallic glass catalysts are often affected by their atomic configuration. Thus, the design and regulation of the nanoscale structure of metallic glasses to improve their catalytic efficiency and stability remains a challenge. Herein, a non‐noble component, Fe75P15C10 amorphous ribbon, is used as a precursor to fabricate a hierarchical gradient catalyst with nanoscale heterogeneous and oxygenous amorphous structure by simple annealing and acid‐immersing. The resulting catalyst offers an ultrahigh catalytic ability of kSA•C0 = 3101 mg m−2 min−1 and excellent reusability of 39 times without efficiency decay in dye wastewater degradation. Theoretical calculations indicate that the excellent catalytic performance of the catalyst can be attributed to its unique heterogeneous nanoglass structure, which induces oxygen atoms. Compared to the FePC structure, the FeP/FePCO structure exhibits strong charge transferability, and the energy barrier of the rate‐determining steps of the conversion of S2O82− to SO4−• is reduced from 2.52 to 0.97 eV. This study reveals that a heterogeneous nanoglass structure is a new strategy for obtaining high catalytic performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • Polyphasic nanostructure catalyst has been fabricated by pulsed laser processing. • 80 W achieves a record catalytic ability of k SA • C 0 = 7733 mg·m−2·min−1 in RR195. • 80 W catalyst exhibits a strong reusability of 28 times without efficiency decay. • Degradation pathway of RR195 molecule in the persulfate system was speculated. • Energy barrier of RDS for conversion of S 2 O 8 2− to SO 4 −• in 80 W is only 1.34 eV. An Fe 73.5 Si 13.5 B 9 Cu 1 Nb 3 amorphous ribbon was used as a precursor to fabricate biphasic and polyphasic nanostructure catalysts via pulsed laser processing. The enhancement in nanostructure heterogeneity, light absorption ability, surface hydrophilicity and photothermal conversion of the catalyst resulted in improving photocatalytic performance, evidenced by a higher k value, increased total organic carbon removal rate, and lower Δ E value. The degradation pathway of reactive red 195 molecules in the persulfate system was proposed. Density-functional theory simulations indicated that the excellent catalytic performance of the pulsed laser catalyst was due to its unique polyphasic nanostructure, which induced the reduction in the energy barrier of the rate-determining step (from 2.74 to 1.34 eV) during the conversion of S 2 O 8 2− to SO 4 −•. The processed catalyst exhibited an ultrahigh catalytic ability of k SA • C 0 = 7733 mg·m−2·min−1 and strong reusability (28 cycles) without efficiency decay. This study revealed that regulating the nanostructure of the catalyst is an effective strategy to achieve high photocatalytic performance. [ABSTRACT FROM AUTHOR]

Mg-based alloys exhibit a good degradation performance in wastewater treatment containing dyes. The degradation performance of as-spun Mg crystalline ribbon, Mg 78 Zn 22 (MZ) semi-amorphous ribbon and Mg 73 Zn 22 Ca 5 (MZC) amorphous ribbon on acidic orange dye (AO II) solution is improved apparently by citric acid (CA) solution immersion. The degradation rate constant k of MZ ribbon after immersing for 1 h reaches 0.084 min−1, showing a much higher degradation efficiency than other immersed ribbons. Compared with the immersed Mg and MZC ribbons, the surface of immersed MZ ribbon has a developed loofah porous structure and an appropriate crystallization. Here, the crystallization induced porous structure is composed of Zn and ZnO, which can generate more nascent hydrogen [H] by transporting Mg atoms to surface and more O 2 • − radical by supplying photo-catalytic ZnO under visible light and then enhance the degradation of AO II dye. This work not only proposes a new method to improve the degradation efficiency of AO II dye by Mg-based alloys, but also provides a new insight into the microstructure and properties of Mg-based alloys. Image 1 • Crystalline, semi-amorphous and amorphous Mg-based ribbons have been melt-spun. • Immersed semi-amorphous ribbon has a high degradation efficiency of AO Ⅱ dye. • Its high efficiency is due to the loofah porous structure on ribbon surface. • ZnO on ribbon surface also has an important contribution to dye degradation. [ABSTRACT FROM AUTHOR]