Regulating the reaction pathway of nZVI to improve the decontamination performance through magnetic spatial confinement effect.
J Hazard Mater
; 447: 130799, 2023 Apr 05.
Article
en En
| MEDLINE
| ID: mdl-36680900
Nanoscale zero-valent iron (nZVI) shows high effectiveness in the catalyzed removal of contaminants in wastewater treatment. However, the uncontrolled interfacial electron transfer behavior and formation of surface iron oxide (FeOx) layer led to severe electron wasting and occasionally form highly toxic intermediates. Here, we constructed magnetic mesoporous SiO2 shell on surface of nZVI to stimulate a magnetic spatial confinement effect and regulate the electron transfer pattern. Therein, Fe atom facilely spread out from the nZVI core, orderly release electron to surface adsorbed H2O molecule, which is efficiently transformed into active hydrogen (H*). Meanwhile, in-situ Raman revealed that Fe atoms were involved in the formation of penetrable γ-FeOOH rather than FeOx layer, enabling the continuous inward diffusion of H2O and outward diffusion of H* . Employing the catalyzed removal of halogenated phenols as demo reaction, the presence of magnetic mesoporous SiO2 shell utilized the reaction between electrons and H2O to switch the reaction pathway from the reduction/oxidation hybrid process to hydrodehalogantion, and increased the conversion of halogenated phenols-to-phenols by 5.53 times. This study shows the forehand of improving the decontamination performance of nZVI through sophisticated designed surface coating, as well as fine regulating the environmental behavior of magnetic material via micro-magnetic field.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Idioma:
En
Revista:
J Hazard Mater
Asunto de la revista:
SAUDE AMBIENTAL
Año:
2023
Tipo del documento:
Article
País de afiliación:
China
Pais de publicación:
Países Bajos