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The design and development of cost-effective and highly efficient oxygen evolution reaction (OER) electrocatalysts are urgently desirable during the water-splitting process. Here, Ni x Fe 80-x B 20 (x = 70, 60, 50, 40, 30, hereafter referred to as NFB) amorphous alloys, with high mechanical strength, excellent corrosion resistance, and unique atomic structure, are fabricated as efficient water oxidation electrocatalysts in alkaline solutions. Ni 40 Fe 40 B 20 amorphous ribbons achieve only 319 mV of overpotential at 10 mA·cm−2 with a Tafel slope of 56 mV dec−1 and exhibit excellent long-term stability for 24 h at 10 mA·cm−2 and 100 mA·cm−2 in 1 M KOH solution, which outperform the commercial RuO 2 electrocatalyst. It is worth noting that the OER performance of Ni x Fe 80-x B 20 amorphous electrocatalysts after long-term chronopotentiometry test displays more effectively, which can be ascribed to the surface construction. Meanwhile, the analysis of the morphology and structure of the electrocatalysts reveal that continuous oxidation during the OER process induces the structural reorganization on the surface of the electrocatalysts, which can enhance the electron transfer process and adsorption of the reaction intermediates to optimize the OER performance. This study provides a shred of evidence for surface self-reconstruction of NiFeB amorphous alloys electrocatalysts during the OER process and promotes the application of amorphous alloys as functional materials in the water-splitting field. [Display omitted] • Amorphous Ni 40 Fe 40 B 20 alloys show a low overpotential of 319 mV at 10 mA·cm−2. • Long-term stability of amorphous NFB alloys in a concentrated alkaline solution. • Self-construction enhances the OER performance after the long-term test. • Promoting the application of amorphous NFB alloys as electrodes. [ABSTRACT FROM AUTHOR]

Fe-based metallic glasses (MGs) not only are an industrially produced amorphous zero-valent iron (AZVI) with a promising reductive degradability to azo dyes but also can activate persulfate (PS) with sulfate radicals (SO 4 •-, E o = 2.5–3.1V) for wastewater remediation. In this study, acid orange II (AOII) was rapidly and efficiently decolored by Fe 78 Si 8 B 14 MG/PS system with a 99% degradation rate in 8 min. Based on monitoring the degradation rate and the concentration of Fe2+/Fe3+, a two-step degradation mechanism is proposed, that one is deductive degradation by AZVI with products of small organic molecules and Fe2+, and the other is oxidative degradation, where AZVI and Fe2+ activate PS with products of SO 4 •- and •OH confirmed by the electron spin resonance (ESR) analysis test. The orthogonal experimental design proves that the effects of the experiment operating parameters on the decolorization efficiency from high to low are Fe-based MGs dosage, PS dosage, and reaction temperature. Meanwhile, the high efficiency of the Fe-based MGs/PS system is also illustrated for the mineralization of AOII by an indication of the TOC removal rate as high as 57%. This work gives new insight into Fe-based MGs for activating PS and will accelerate the application of Fe-based MGs as catalysts in the field of wastewater treatment. • Fe-based MGs plays the most important role in the decolorization of AOII based on the orthogonal experiments design. • A two-step synergetic decolorization mechanism for the AOII decolorization is proposed. • The Ea of Fe-based MG/PS system is11.556kJ/mol, much lower than other systems for the decolorization of azo dyes. [ABSTRACT FROM AUTHOR]