“Switching on” iron in clay minerals

doi:https://doi.org/10.1039/c9en00228f

Title: “Switching on” iron in clay minerals

Abstract

Being the fourth most abundant element in the Earth’s crust, iron (Fe) is a key player in myriad biogeochemical processes. Iron that resides in clay mineral structures undergoes cycling between Fe(II) and Fe(III). This iron comprises a large redox-active pool in surface environments, controlling the fate and transport of nutrients and contaminants. The electron transfer involving this iron species is poorly understood. We observe that Fe(III) in clay minerals is not redox active, unless a minor amount of Fe(II) is introduced into the predominantly-Fe(III) structure. These “activated” clay minerals are redox-active both in the presence and absence of oxygen. In the presence of oxygen, Fe(II) catalyzes the production of reactive oxygen species; however, the oxidation pathway in the absence of oxygen is unknown. Here we show that under oxygen-free conditions, the redox-active species in clay minerals is FeII-O-FeIII moiety at the edge site. Our ab initio calculations illustrate that desorption of water from an FeII-O-FeIII site in clay mineral requires less energy, compared to an FeIII-O-FeIII site. We propose that this lower barrier for the desorption of water increases the apparent kinetics of redox reactions on clay mineral surfaces.

Authors:

Ilgen, Anastasia G. ^[1];

^[2]; Leung, Kevin ^[3]; Washington, Rachel E. ^[1]

Sandia National Laboratory
BATTELLE (PACIFIC NW LAB)
Sandia National Laboratories

Publication Date:: 2019-07-01

Research Org.:: Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

Sponsoring Org.:: USDOE

OSTI Identifier:: 1567049

Report Number(s):: PNNL-SA-139445

DOE Contract Number:: AC05-76RL01830

Resource Type:: Journal Article

Journal Name:: Environmental Science Nano

Additional Journal Information:: Journal Volume: 6; Journal Issue: 6

Country of Publication:: United States

Language:: English

Citation Formats


                    Ilgen, Anastasia G., Kukkadapu, Ravi K., Leung, Kevin, and Washington, Rachel E. “Switching on” iron in clay minerals.  United States: N. p., 2019. 
        Web.  doi:10.1039/c9en00228f.

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                    Ilgen, Anastasia G., Kukkadapu, Ravi K., Leung, Kevin, & Washington, Rachel E. “Switching on” iron in clay minerals.  United States.  https://doi.org/10.1039/c9en00228f

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                    Ilgen, Anastasia G., Kukkadapu, Ravi K., Leung, Kevin, and Washington, Rachel E. Mon .  
        "“Switching on” iron in clay minerals".  United States.  https://doi.org/10.1039/c9en00228f.

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@article{osti_1567049,

  title        = {“Switching on” iron in clay minerals},

  author       = {Ilgen, Anastasia G. and Kukkadapu, Ravi K. and Leung, Kevin and Washington, Rachel E.},

  abstractNote = {Being the fourth most abundant element in the Earth’s crust, iron (Fe) is a key player in myriad biogeochemical processes. Iron that resides in clay mineral structures undergoes cycling between Fe(II) and Fe(III). This iron comprises a large redox-active pool in surface environments, controlling the fate and transport of nutrients and contaminants. The electron transfer involving this iron species is poorly understood. We observe that Fe(III) in clay minerals is not redox active, unless a minor amount of Fe(II) is introduced into the predominantly-Fe(III) structure. These “activated” clay minerals are redox-active both in the presence and absence of oxygen. In the presence of oxygen, Fe(II) catalyzes the production of reactive oxygen species; however, the oxidation pathway in the absence of oxygen is unknown. Here we show that under oxygen-free conditions, the redox-active species in clay minerals is FeII-O-FeIII moiety at the edge site. Our ab initio calculations illustrate that desorption of water from an FeII-O-FeIII site in clay mineral requires less energy, compared to an FeIII-O-FeIII site. We propose that this lower barrier for the desorption of water increases the apparent kinetics of redox reactions on clay mineral surfaces.},

  doi          = {10.1039/c9en00228f},

  url          = {https://www.osti.gov/biblio/1567049},
  journal      = {Environmental Science Nano},
number       = 6,

  volume       = 6,

  place        = {United States},

  year         = {2019},

  month        = {7}

}

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Title: “Switching on” iron in clay minerals

Abstract

Citation Formats

Reactivity of Fe(II) Species Associated with Clay Minerals journal, February 2003

Heterogeneous reduction of Tc(VII) by Fe(II) at the solid–water interface journal, March 2008

Partitioning of Fe(II) in reduced nontronite (NAu-2) to reactive sites: reactivity in terms of Tc(VII) reduction journal, April 2008

Interaction between aqueous chromium solutions and layer silicates journal, October 2000

Role of structural Fe in nontronite NAu-1 and dissolved Fe(II) in redox transformations of arsenic and antimony journal, October 2012

Production of Abundant Hydroxyl Radicals from Oxygenation of Subsurface Sediments journal, December 2015

Mechanisms of electron transfer from structrual Fe(II) in reduced nontronite to oxygen for production of hydroxyl radicals journal, February 2018

Spectroscopic Investigations of Fe 2+ Complexation on Nontronite Clay journal, January 2007

Oxidation-reduction mechanism of iron in dioctahedral smectites: II. Crystal chemistry of reduced Garfield nontronite journal, January 2000

Oxidation-reduction mechanism of iron in dioctahedral smectites: I. Crystal chemistry of oxidized reference nontronites journal, January 2000

Site Occupancies by Iron in Nontronites journal, April 2002

Synthesis and characterization of redox-active ferric nontronite journal, October 2017

Comparisons of structural iron reduction in smectites by bacteria and dithionite: II. A variable-temperature Mössbauer spectroscopic study of Garfield nontronite journal, July 2009

Redox Properties of Structural Fe in Clay Minerals: 3. Relationships between Smectite Redox and Structural Properties journal, November 2013

Reduction of Nitroaromatic Compounds by Fe(II) Species Associated with Iron-Rich Smectites journal, January 2006

Redox Properties of Structural Fe in Clay Minerals. 1. Electrochemical Quantification of Electron-Donating and -Accepting Capacities of Smectites journal, August 2012

Redox Properties of Structural Fe in Clay Minerals. 2. Electrochemical and Spectroscopic Characterization of Electron Transfer Irreversibility in Ferruginous Smectite, SWa-1 journal, August 2012

Control of Fe(III) site occupancy on the rate and extent of microbial reduction of Fe(III) in nontronite journal, December 2005

Spectroscopic Evidence for Fe(II)–Fe(III) Electron Transfer at Clay Mineral Edge and Basal Sites journal, March 2013

Spectroscopic Evidence for Interfacial Fe(II)−Fe(III) Electron Transfer in a Clay Mineral journal, January 2011

Probing the importance of planar surfaces and crystal edges for electron transfer within iron-bearing clays journal, January 2014

Insights into the Mechanism of Fe(II) Adsorption and Oxidation at Fe–Clay Mineral Surfaces from First-Principles Calculations journal, October 2013

Redox Transformations of As and Se at the Surfaces of Natural and Synthetic Ferric Nontronites: Role of Structural and Adsorbed Fe(II) journal, September 2017

Electrochemical trapping of metastable Mn 3+ ions for activation of MnO 2 oxygen evolution catalysts journal, May 2018

Preparation and Handling of Dithionite-Reduced Smectite Suspensions journal, January 1984

ATHENA , ARTEMIS , HEPHAESTUS : data analysis for X-ray absorption spectroscopy using IFEFFIT journal, June 2005

IFEFFIT : interactive XAFS analysis and FEFF fitting journal, March 2001

Near-edge x-ray-absorption fine structure of Pb: A comparison of theory and experiment journal, June 1993

Multiple-scattering calculations of x-ray-absorption spectra journal, July 1995

Voigt-based methods for arbitrary-shape static hyperfine parameter distributions in Mössbauer spectroscopy journal, May 1991

Pertechnetate (TcO4−) reduction by reactive ferrous iron forms in naturally anoxic, redox transition zone sediments from the Hanford Site, USA journal, September 2012

Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set journal, October 1996

Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set journal, July 1996

From ultrasoft pseudopotentials to the projector augmented-wave method journal, January 1999

Why does the B3LYP hybrid functional fail for metals? journal, July 2007

Generalized Gradient Approximation Made Simple journal, October 1996

Polarized EXAFS, distance-valence least-squares modeling (DVLS), and quantitative texture analysis approaches to the structural refinement of Garfield nontronite journal, May 1998

Influence of Coprecipitated Organic Matter on Fe 2+ (aq) -Catalyzed Transformation of Ferrihydrite: Implications for Carbon Dynamics journal, July 2015

Redox Fluctuations Control the Coupled Cycling of Iron and Carbon in Tropical Forest Soils journal, November 2018

Electron Exchange and Conduction in Nontronite from First-Principles journal, January 2013

Quantifying surface areas of clays by atomic force microscopy journal, May 2002

Redox Transformation of Arsenic by Fe(II)-Activated Goethite (α-FeOOH) journal, January 2010

Effects of pH, dissolved oxygen, and aqueous ferrous iron on the adsorption of arsenic to lepidocrocite journal, June 2015

Electron-energy-loss spectra and the structural stability of nickel oxide: An LSDA+U study journal, January 1998

Reactivity of Fe(II) Species Associated with Clay Minerals
journal, February 2003

Heterogeneous reduction of Tc(VII) by Fe(II) at the solid–water interface
journal, March 2008

Partitioning of Fe(II) in reduced nontronite (NAu-2) to reactive sites: reactivity in terms of Tc(VII) reduction
journal, April 2008

Interaction between aqueous chromium solutions and layer silicates
journal, October 2000

Role of structural Fe in nontronite NAu-1 and dissolved Fe(II) in redox transformations of arsenic and antimony
journal, October 2012

Production of Abundant Hydroxyl Radicals from Oxygenation of Subsurface Sediments
journal, December 2015

Mechanisms of electron transfer from structrual Fe(II) in reduced nontronite to oxygen for production of hydroxyl radicals
journal, February 2018

Spectroscopic Investigations of Fe ²⁺ Complexation on Nontronite Clay
journal, January 2007

Oxidation-reduction mechanism of iron in dioctahedral smectites: II. Crystal chemistry of reduced Garfield nontronite
journal, January 2000

Oxidation-reduction mechanism of iron in dioctahedral smectites: I. Crystal chemistry of oxidized reference nontronites
journal, January 2000

Site Occupancies by Iron in Nontronites
journal, April 2002

Synthesis and characterization of redox-active ferric nontronite
journal, October 2017

Comparisons of structural iron reduction in smectites by bacteria and dithionite: II. A variable-temperature Mössbauer spectroscopic study of Garfield nontronite
journal, July 2009

Redox Properties of Structural Fe in Clay Minerals: 3. Relationships between Smectite Redox and Structural Properties
journal, November 2013

Reduction of Nitroaromatic Compounds by Fe(II) Species Associated with Iron-Rich Smectites
journal, January 2006

Redox Properties of Structural Fe in Clay Minerals. 1. Electrochemical Quantification of Electron-Donating and -Accepting Capacities of Smectites
journal, August 2012

Redox Properties of Structural Fe in Clay Minerals. 2. Electrochemical and Spectroscopic Characterization of Electron Transfer Irreversibility in Ferruginous Smectite, SWa-1
journal, August 2012

Control of Fe(III) site occupancy on the rate and extent of microbial reduction of Fe(III) in nontronite
journal, December 2005

Spectroscopic Evidence for Fe(II)–Fe(III) Electron Transfer at Clay Mineral Edge and Basal Sites
journal, March 2013

Spectroscopic Evidence for Interfacial Fe(II)−Fe(III) Electron Transfer in a Clay Mineral
journal, January 2011

Probing the importance of planar surfaces and crystal edges for electron transfer within iron-bearing clays
journal, January 2014

Insights into the Mechanism of Fe(II) Adsorption and Oxidation at Fe–Clay Mineral Surfaces from First-Principles Calculations
journal, October 2013

Redox Transformations of As and Se at the Surfaces of Natural and Synthetic Ferric Nontronites: Role of Structural and Adsorbed Fe(II)
journal, September 2017

Electrochemical trapping of metastable Mn ³⁺ ions for activation of MnO ₂ oxygen evolution catalysts
journal, May 2018

Preparation and Handling of Dithionite-Reduced Smectite Suspensions
journal, January 1984

ATHENA , ARTEMIS , HEPHAESTUS : data analysis for X-ray absorption spectroscopy using IFEFFIT
journal, June 2005

IFEFFIT : interactive XAFS analysis and FEFF fitting
journal, March 2001

Near-edge x-ray-absorption fine structure of Pb: A comparison of theory and experiment
journal, June 1993

Multiple-scattering calculations of x-ray-absorption spectra
journal, July 1995

Voigt-based methods for arbitrary-shape static hyperfine parameter distributions in Mössbauer spectroscopy
journal, May 1991

Pertechnetate (TcO4−) reduction by reactive ferrous iron forms in naturally anoxic, redox transition zone sediments from the Hanford Site, USA
journal, September 2012

Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set
journal, October 1996

Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set
journal, July 1996

From ultrasoft pseudopotentials to the projector augmented-wave method
journal, January 1999

Why does the B3LYP hybrid functional fail for metals?
journal, July 2007

Generalized Gradient Approximation Made Simple
journal, October 1996

Polarized EXAFS, distance-valence least-squares modeling (DVLS), and quantitative texture analysis approaches to the structural refinement of Garfield nontronite
journal, May 1998

Influence of Coprecipitated Organic Matter on Fe ²⁺ _(aq) -Catalyzed Transformation of Ferrihydrite: Implications for Carbon Dynamics
journal, July 2015

Redox Fluctuations Control the Coupled Cycling of Iron and Carbon in Tropical Forest Soils
journal, November 2018

Electron Exchange and Conduction in Nontronite from First-Principles
journal, January 2013

Quantifying surface areas of clays by atomic force microscopy
journal, May 2002

Redox Transformation of Arsenic by Fe(II)-Activated Goethite (α-FeOOH)
journal, January 2010

Effects of pH, dissolved oxygen, and aqueous ferrous iron on the adsorption of arsenic to lepidocrocite
journal, June 2015

Electron-energy-loss spectra and the structural stability of nickel oxide: An LSDA+U study
journal, January 1998