Activation of peroxymonosulfate by Fe78Si9B13 metallic glass: The influence of crystallization

[摘要] Exploring functional applications as heterogeneous catalysts is an active topic for metallic glasses (MGs). Although recent advances have shown that the MGs with disordered atomic packing structure are indeed having superior catalytic reactivity for wastewater remediation, the catalytic mechanism is not yet clear. Herein, crystallization in melt-spun Fe78Si9B13 glassy ribbons was applied at various annealing temperatures for understanding the catalytic mechanism. The crystalline structures and volume fractions of the crystallized alpha-Fe in the as-received and annealed glassy ribbons were fully characterized. The results showed that Fe78Si9B13 glassy ribbons with disordered atomic structure present enhanced catalytic performance for peroxymonosulfate (PMS) activation compared to annealed counterparts with partially crystalline atomic structure. The degradation of five dyes were investigated in view of practical applications. The reaction conditions, such as catalyst dosage, PMS concentration, light intensity as well as salinity and natural organic matters, were fully studied. Quenching experiments were performed to qualitatively identify the generation of center dot OH and SO4 center dot-. The mechanism of PMS activation by MGs was also proposed. This critical study sheds new insights into the catalytic mechanism for higher catalytic performance of amorphous catalysts compared with crystalline counterparts, providing an effective strategy to design catalysts for improving the overall catalytic activity. (C) 2017 Elsevier B.V. All rights reserved.

[发布日期] 2017-12-25

[关键词] Metallic glass;Crystallization;Heterogeneous catalysis;Peroxymonosulfate;Sulfate radicals