Magnetically separable Z-scheme FeSiB metallic glass/g-C3N4 heterojunction photocatalyst with high degradation efficiency at universal pH conditions

Abstract

Abstract Synthesizing efficient catalysts to degrade hazardous pollutants in wastewater, especially in alkaline conditions, is pivotal for water remediation. A magnetically separable Z-scheme FeSiB metallic glass (MG)/g-C3N4 photocatalyst with high activity under visible-light irradiation is prepared via ball milling. The photocatalyst exhibits a sufficient degrading capability to acid orange 7 (AO7) in acidic, neutral and alkaline solutions, and also shows excellent reusability. The photocatalytic efficiency of the composite can be optimized by modifying the weight ratio of FeSiB MG and g-C3N4 powders. Heterojunction structure is formed at the interface of g-C3N4 and FeSiB MG due to the shearing stress from ball milling, leading to the improvement of the separation efficiency of the photo-generated electron-hole pairs. This results in the enhancement in photocatalytic activity for the composite. Besides, the FeSiB MG/g-C3N4 photocatalyst can be recycled from solution conveniently due to their high saturation magnetization. This study offers a magnetically separable photocatalyst that can degrade azo dyes at universal pH conditions.