Fe-based metallic glass as heterogeneous Fenton-like catalyst for azo dyes degradation: effect of inorganic anions

Metallic glasses (MGs) are promising heterogeneous catalysts in water remediation, due to their superior efficiency, selectivity, reusability and corrosion resistance. However, few works are focused on the influence of inorganic anions that are abundant in wastewater. Herein, four common inorganic anions were added in a heterogeneous Fenton-like system (Fe-MG/H2O2) to study inorganic anions' influence on MGs' catalytic performance during methylene blue (MB) degradation. Evidence demonstrated that chloride ions and dihydrogen phosphate ions had an adverse effect on the catalytic performance of Fe-MG, whereas Fe-MG/H2O2 system sustained high efficiency in the presence of sulfate ions and nitrate ions during the Fenton-like process. By studying the structure, surface morphology, and evolution of active species, it was found that inorganic anions had a significant effect on the surface morphology of Fe-MG and the generation of active species. This work will provide essential references for MGs as heterogeneous catalysts in practical applications.