Impacts of shell structure on nitrate-reduction activity and air stability of nanoscale zero-valent iron

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

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Author(s)

  • Miao Gao
  • Yingchao Huo
  • Houqi Liu
  • Jie Li
  • Tianyin Huang
  • Wenwei Li

Detail(s)

Original languageEnglish
Journal / PublicationEnvironmental Science and Pollution Research
Online published21 Jun 2022
Publication statusOnline published - 21 Jun 2022

Abstract

Nanoscale zero-valent iron (nZVI) has been intensively studied for pollution control because of its high reductive activity and environmental benignity, but the poor reaction selectivity and the aging problem have limited its practical decontamination application. Here, we shed light on the impacts of nZVI shell structure on its reactivity and air stability by systematically comparing two nZVI materials with distinct iron oxide shells. The nZVI with highly crystalline and weakly hydrophilic shell exhibited ninefold higher intrinsic activity for nitrate reduction and significantly improved air stability than that with amorphous, hydrophilic iron hydroxide oxide shell. The compact-structured crystalline shell of nZVI facilitated more efficient interfacial electronic transfer for nitrate reduction and suppressed side reaction of hydrogen evolution. The protective hematite shell endowed the nZVI with significantly improved anti-aging ability, and the reducing force remained 92.6% after exposed to air for 10 days due to decreased oxygen diffusion. This work provides a better understanding of the pollutant degradation behavior of nZVI and may guide an improved synthesis and environmental application of nZVI.

Research Area(s)

  • Nanoscale zero-valent iron (nZVI), Shell structure, Crystalline, Hydrophilic, Nitrate reduction activity, Air stability, ZEROVALENT IRON, MAGNESIUM-HYDROXIDE, NANOPARTICLES, NZVI, REMOVAL, WATER, NANO, REMEDIATION, TRANSFORMATION, SEQUESTRATION

Citation Format(s)