The origins of potentially superior properties and multifunctionalities of carbon-nano zero-valent iron in the carbonization pyrolysis process

Abstract

Although carbon-nano zero-valent iron (C@nZVI) composites with unique properties have been used for environmental remediation, the origins of their superior properties and multifunctionalities of C@nZVI still need to be verified. Here, iron precursor nanoparticles (PML-Fe NPs) synthesized by Pinus massoniana Lamb and carbonized C@nZVI were systemically compared to reveal the origins of the structure and performance of C@nZVI composites. Characterizations showed that structure-modulated C@nZVI has favorable properties of good crystallinity, graphite carbon-rich structure but also defects when compared to PML-Fe NPs. The resultant carbon layer fundamentally improved its dispersion and anti-oxidation properties. Further experiments demonstrated that the evolution of material crystallinity, graphitization and defects affected the reaction pathway of hexavalent chromium (Cr(VI)), oxytetracycline hydrochloride (OTC), and 17β-estradiol (βE₂). The multifunctionalities covered adsorption, reduction and catalytic oxidation. This study explains the origins of multifunctional C@nZVI by understanding the structure-property correlation in the carbonization process.

Keywords: Carbon-nano zero-valent iron; Origins; Reaction pathway; Structure-property correlation.