Experimental and theoretical study on the reactivity of maghemite doped with Cu2 in oxidation reactions: structural and thermodynamic properties towards a Fenton catalyst

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F62690094%3A18450%2F16%3A50005047" target="_blank" >RIV/62690094:18450/16:50005047 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1039/c6ra11032k" target="_blank" >http://dx.doi.org/10.1039/c6ra11032k</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1039/c6ra11032k" target="_blank" >10.1039/c6ra11032k</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Experimental and theoretical study on the reactivity of maghemite doped with Cu2 in oxidation reactions: structural and thermodynamic properties towards a Fenton catalyst

Popis výsledku v původním jazyce

In this work, a polymeric method was used to prepare undoped and Cu-doped iron oxide catalysts for the H2O2 decomposition reaction. These catalysts were characterized by powder X-ray diffractometry (XRD), scanning electronic microscopy (SEM) coupled to an energy dispersive X-ray spectrometer (EDX), and H2-Temperature Programmed Reduction (H2-TPR). The SEM images show an inhomogeneous particle cluster in both samples, tending to decrease in size with Cu-doping. EDX mapping reveals a good dispersion of Cu2+ in the iron oxide. In addition, Rietveld refinement of the XRD patterns reveals that the samples are constituted of hematite and maghemite, but only maghemite has octahedral Fe3+ ions isomorphically replaced by 2 wt% Cu2+. Cu-doping produces an active catalyst for H2O2 decomposition. Tests using phenol show the strong inhibition of H2O2 decomposition by the Cu-doped catalysts, suggesting that H2O2 may be decomposed via a radical mechanism. Furthermore, phenol degradation kinetics confirm that the doping of maghemite with Cu2+ brings about a significant improvement in catalytic activity. Theoretical calculations reveal that Cu-doping in maghemite produces low electronic density sites, favoring the interactions between the surface oxygens of H2O2 and Cu2+, thus improving the catalytic activity. This strategy can be extended to other materials to design active heterogeneous catalysts for environmental purposes.

Název v anglickém jazyce

Experimental and theoretical study on the reactivity of maghemite doped with Cu2 in oxidation reactions: structural and thermodynamic properties towards a Fenton catalyst

Popis výsledku anglicky

In this work, a polymeric method was used to prepare undoped and Cu-doped iron oxide catalysts for the H2O2 decomposition reaction. These catalysts were characterized by powder X-ray diffractometry (XRD), scanning electronic microscopy (SEM) coupled to an energy dispersive X-ray spectrometer (EDX), and H2-Temperature Programmed Reduction (H2-TPR). The SEM images show an inhomogeneous particle cluster in both samples, tending to decrease in size with Cu-doping. EDX mapping reveals a good dispersion of Cu2+ in the iron oxide. In addition, Rietveld refinement of the XRD patterns reveals that the samples are constituted of hematite and maghemite, but only maghemite has octahedral Fe3+ ions isomorphically replaced by 2 wt% Cu2+. Cu-doping produces an active catalyst for H2O2 decomposition. Tests using phenol show the strong inhibition of H2O2 decomposition by the Cu-doped catalysts, suggesting that H2O2 may be decomposed via a radical mechanism. Furthermore, phenol degradation kinetics confirm that the doping of maghemite with Cu2+ brings about a significant improvement in catalytic activity. Theoretical calculations reveal that Cu-doping in maghemite produces low electronic density sites, favoring the interactions between the surface oxygens of H2O2 and Cu2+, thus improving the catalytic activity. This strategy can be extended to other materials to design active heterogeneous catalysts for environmental purposes.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10609 - Biochemical research methods

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2016

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

RSC advances

ISSN

2046-2069

e-ISSN

—

Svazek periodika

6

Číslo periodika v rámci svazku

84

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

10

Strana od-do

80830-80839

Kód UT WoS článku

000383903500054

EID výsledku v databázi Scopus

2-s2.0-84985020796