Enhanced Fenton-like catalytic performance of Fe-based metallic glass by nitrogen microalloying

Abstract

Metallic glasses (MGs) have attracted extensive attention in functional applications due to their long-range disordered atomic arrangement, making them as promising Fenton-like catalysts for wastewater treatment. However, due to the compositional limitations imposed by glass-forming ability, promoting catalytic degradation ability of MGs while retaining their disordered structure becomes challenging in alloy design. Inspired by the regulation function of electronic structure combined with atomic size-dependent structural disordering by nitrogen (N), herein, the microalloying of 0.2 at.% N in Fe₇₈Si₉B₁₃ MG is reported to show a significantly improved catalytic efficiency and stability for the degradation of rhodamine B (RhB) dye. Mechanistic investigations suggest that N microalloying effectively regulates the electron transfer efficiency and suppresses the surface coverage of oxides on Fe₇₈Si₉B₁₃ MG, thereby exposing abundant active sites (Fe⁰) for degradation reaction. In addition, the refinement of post-reaction surface products contributes to a strong diffusion and capture of reactants (e.g. H₂O₂ and dye molecules), facilitating the H₂O₂ activation and radical generation for enhanced degradation stability. This study provides a new perspective for material design in MG catalysts.