>> Transformation pathway and degradation mechanism of methylene blue through Β-FeOOH@GO catalyzed photo-Fenton-like system

2021-06-25阅:348

题名:Transformation pathway and degradation mechanism of methylene blue through Β-FeOOH@GO catalyzed photo-Fenton-like system

来源:Chemosphere

发表年代:2019

作者:Shanshan Su, Yuyang Liu, Xuemin Liu, Wei Jin, Yaping Zhao*

Abstract  To enhance the catalytic and separation properties of akaganéite nanoparticles, rice spike-like akaganéite impregnated graphene oxide (β-FeOOH@GO) nanocomposite was fabricated through facile hydrolysis. The apparent first-order decolorization rate of methylene blue (MB) in β-FeOOH@GO catalyzed photo Fenton-like system was 0.6322 min−1 about 3 folds that of prinstine β-FeOOH nanoparticles. The degradation intermediates of MB adsorbed on the solid surface of β-FeOOH@GO were comprehensively identified with time of flight-secondary ion mass spectroscopy (TOF-SIMS) for the first time. Newly identified sulfoxide intermediates, sulphone intermediates and desulfurization intermediates and N-demethylaton or dedimethamine intermediates were reported for the first time. The proposed degradation pathway of MB predominantly proceeded with the rupture of phenothiazine rings oxided with radical dotOH,

 

Image 1 and singlet oxygen (1O2) radicals, which fully extending the reaction pathways proposed in previous work in literature. The enhanced catalytic activity of β-FeOOH@GO was ascribed to the formation of heterojunctions confirmed by the presence of Fesingle bondOsingle bondC chemical bonds through X-ray photoelectron spectroscopy (XPS). The complete elimination of MB and its acute toxicity to Luminous bacteria showed that β-FeOOH@GO would be served as a highly efficient Fenton-like catalyst for treatment of high concentration refractory organic contaminant.

Transformation-pathway-and-degradation-mechanism-of-methylene-blue-through-FeOOHGO-catalyzed-photoFentonlike-systemChemosphere.pdf