Ultra-sustainable Fe78Si9B13 metallic glass as a catalyst for activation of persulfate on methylene blue degradation under UV-Vis light.

Zhe Jia,Wenchang Zhang,Shaobin Wang,Xiaoguang Duan,Lai-Chang Zhang,Hongqi Sun,Weimin Wang

doi:10.1038/srep38520

Abstract

Stability and reusability are important characteristics of advanced catalysts for wastewater treatment. In this work, for the first time, sulfate radicals (SO4∙−) with a high oxidative potential (Eo = 2.5–3.1 V) were successfully activated from persulfate by a Fe78Si9B13 metallic glass. This alloy exhibited a superior surface stability and reusability while activating persulfate as indicated by it being used for 30 times while maintaining an acceptable methylene blue (MB) degradation rate. The produced SiO2 layer on the ribbon surface expanded strongly from the fresh use to the 20th use, providing stable protection of the buried Fe. MB degradation and kinetic study revealed 100% of the dye degradation with a kinetic rate k = 0.640 within 20 min under rational parameter control. The dominant reactive species for dye molecule decomposition in the first 10 min of the reaction was hydroxyl radicals (∙OH, Eo = 2.7 V) and in the last 10 min was sulfate radicals (SO4∙−), respectively. Empirical operating variables for dye degradation in this work were under catalyst dosage 0.5 g/L, light irradiation 7.7 μW/cm2, and persulfate concentration 1.0 mmol/L. The amorphous Fe78Si9B13 alloy in this work will open a new gate for wastewater remediation.

Highlights

Stability and reusability are important characteristics of advanced catalysts for wastewater treatment
The diffraction intensities at 2θmax = 53.2° gradually increase with increasing the use times of ribbons, from 1172 counts for fresh use to 1546 counts for 30th used ribbon, considering the same amount of ribbons were used for X-ray diffraction (XRD) characterization
Compared to the fresh Fe78Si9B13 ribbon, all used ribbons present three obvious absorbance peaks at λ= 240 nm, 305 nm and 410 nm. This result indicates that the iron species are still distributed homogeneously and new iron oxides are formed on the used Fe78Si9B13 ribbons during dye degradation[50,51]

Summary

Introduction

Stability and reusability are important characteristics of advanced catalysts for wastewater treatment. For the first time, sulfate radicals (SO4∙−) with a high oxidative potential (Eo = 2.5–3.1 V) were successfully activated from persulfate by a Fe78Si9B13 metallic glass This alloy exhibited a superior surface stability and reusability while activating persulfate as indicated by it being used for 30 times while maintaining an acceptable methylene blue (MB) degradation rate. Fe-based amorphous alloys are a special type of ZVI materials[39], and the ultrafast degradation and mineralization efficiency of hazardous contaminants in the wastewater matrix have been achieved by using Fe-B40, Fe-Si-B13, Fe-Mo-Si-B41, Fe-Si-B-Cu-Nb42 and Fe-Nb-Si-B43 alloys Due to their superior soft magnetic property and chemical stability, Fe-based metallic glasses are readily recycled and have an acceptable level of surface decay, offering the potential for dramatic cost reductions when employed as a catalyst in industrial settings[13,40,41,42,43]

Methods

Results

Conclusion