DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Impact of Sr segregation on the electronic structure and oxygen reduction activity of SrTi1–xFexO3 surfaces

Abstract

The correlation between the surface chemistry and electronic structure is studied for SrTi1–xFexO3 (STF), as a model perovskite system, to explain the impact of Sr segregation on the oxygen reduction activity of cathodes in solid oxide fuel cells. Dense thin films of SrTi0.95Fe0.05O3 (STF5), SrTi0.65Fe0.35O3 (STF35) and SrFeO3 (STF100) were investigated using a coordinated combination of surface probes. Composition, chemical binding, and valence band structure analysis using angle-resolved X-ray photoelectron spectroscopy showed that Sr enrichment increases on the STF film surfaces with increasing Fe content. In situ scanning tunnelling microscopy/spectroscopy results proved the important and detrimental impact of this cation segregation on the surface electronic structure at high temperature and in an oxygen environment. While no apparent band gap was found on the STF5 surface due to defect states at 345 °C and 10–3 mbar of oxygen, the surface band gap increased with Fe content, 2.5 ± 0.5 eV for STF35 and 3.6 ± 0.6 eV for STF100, driven by a down-shift in energy of the valence band. This trend is opposite to the dependence of the bulk STF band gap on the Fe fraction, and is attributed to the formation of a Sr-rich surface phase in the form ofmore » SrOx on the basis of the measured surface band structure. Here, the results demonstrate that Sr segregation on STF can deteriorate oxygen reduction kinetics through two mechanisms – inhibition of electron transfer from bulk STF to oxygen species adsorbing onto the surface and the smaller concentration of oxygen vacancies available on the surface for incorporating oxygen into the lattice.« less

Authors:
 [1];  [1];  [1];  [1];  [1];  [1]
  1. Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
Publication Date:
Research Org.:
Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES)
OSTI Identifier:
1557716
Grant/Contract Number:  
SC0002633
Resource Type:
Accepted Manuscript
Journal Name:
Energy & Environmental Science
Additional Journal Information:
Journal Volume: 5; Journal Issue: 7; Journal ID: ISSN 1754-5692
Publisher:
Royal Society of Chemistry
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY

Citation Formats

Chen, Yan, Jung, WooChul, Cai, Zhuhua, Kim, Jae Jin, Tuller, Harry L., and Yildiz, Bilge. Impact of Sr segregation on the electronic structure and oxygen reduction activity of SrTi1–xFexO3 surfaces. United States: N. p., 2012. Web. doi:10.1039/c2ee21463f.
Chen, Yan, Jung, WooChul, Cai, Zhuhua, Kim, Jae Jin, Tuller, Harry L., & Yildiz, Bilge. Impact of Sr segregation on the electronic structure and oxygen reduction activity of SrTi1–xFexO3 surfaces. United States. https://doi.org/10.1039/c2ee21463f
Chen, Yan, Jung, WooChul, Cai, Zhuhua, Kim, Jae Jin, Tuller, Harry L., and Yildiz, Bilge. Tue . "Impact of Sr segregation on the electronic structure and oxygen reduction activity of SrTi1–xFexO3 surfaces". United States. https://doi.org/10.1039/c2ee21463f. https://www.osti.gov/servlets/purl/1557716.
@article{osti_1557716,
title = {Impact of Sr segregation on the electronic structure and oxygen reduction activity of SrTi1–xFexO3 surfaces},
author = {Chen, Yan and Jung, WooChul and Cai, Zhuhua and Kim, Jae Jin and Tuller, Harry L. and Yildiz, Bilge},
abstractNote = {The correlation between the surface chemistry and electronic structure is studied for SrTi1–xFexO3 (STF), as a model perovskite system, to explain the impact of Sr segregation on the oxygen reduction activity of cathodes in solid oxide fuel cells. Dense thin films of SrTi0.95Fe0.05O3 (STF5), SrTi0.65Fe0.35O3 (STF35) and SrFeO3 (STF100) were investigated using a coordinated combination of surface probes. Composition, chemical binding, and valence band structure analysis using angle-resolved X-ray photoelectron spectroscopy showed that Sr enrichment increases on the STF film surfaces with increasing Fe content. In situ scanning tunnelling microscopy/spectroscopy results proved the important and detrimental impact of this cation segregation on the surface electronic structure at high temperature and in an oxygen environment. While no apparent band gap was found on the STF5 surface due to defect states at 345 °C and 10–3 mbar of oxygen, the surface band gap increased with Fe content, 2.5 ± 0.5 eV for STF35 and 3.6 ± 0.6 eV for STF100, driven by a down-shift in energy of the valence band. This trend is opposite to the dependence of the bulk STF band gap on the Fe fraction, and is attributed to the formation of a Sr-rich surface phase in the form of SrOx on the basis of the measured surface band structure. Here, the results demonstrate that Sr segregation on STF can deteriorate oxygen reduction kinetics through two mechanisms – inhibition of electron transfer from bulk STF to oxygen species adsorbing onto the surface and the smaller concentration of oxygen vacancies available on the surface for incorporating oxygen into the lattice.},
doi = {10.1039/c2ee21463f},
journal = {Energy & Environmental Science},
number = 7,
volume = 5,
place = {United States},
year = {Tue Apr 03 00:00:00 EDT 2012},
month = {Tue Apr 03 00:00:00 EDT 2012}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 165 works
Citation information provided by
Web of Science

Save / Share:

Works referenced in this record:

Relationship between Cation Segregation and the Electrochemical Oxygen Reduction Kinetics of La0.6Sr0.4CoO3−δ Thin Film Electrodes
journal, January 2011

  • Kubicek, Markus; Limbeck, Andreas; Frömling, Till
  • Journal of The Electrochemical Society, Vol. 158, Issue 6
  • DOI: 10.1149/1.3581114

Atomic structures of reduced SrTiO3(001) surfaces
journal, April 1993


Structure change of TiO2-terminated SrTiO3(001) surfaces by annealing in O2 atmosphere and ultrahigh vacuum
journal, February 1999


A Linear Free Energy Relationship for Gas-Solid Interactions: Correlation between Surface Rate Constant and Diffusion Coefficient of Oxygen Tracer Exchange for Electron-Rich Perovskites
journal, September 2004

  • Merkle, Rotraut; Maier, Joachim; Bouwmeester, Henny J. M.
  • Angewandte Chemie International Edition, Vol. 43, Issue 38
  • DOI: 10.1002/anie.200460081

Enhancement of La0.6Sr0.4Co0.2Fe0.8O3-δ durability and surface electrocatalytic activity by La0.85Sr0.15MnO3±δ investigated using a new test electrode platform
journal, January 2011

  • Lynch, Matthew E.; Yang, Lei; Qin, Wentao
  • Energy & Environmental Science, Vol. 4, Issue 6
  • DOI: 10.1039/c1ee01188j

Variation of the Electronic Structure in Systematically Synthesized Sr 2 M O 4 ( M = Ti , V, Cr, Mn, and Co)
journal, October 2005


Structures and chemistry of the annealed SrTiO3(001) surface
journal, May 1994


The compound Sr 3 Ti 2 O 7 and its structure
journal, January 1958


In situ characterization of strontium surface segregation in epitaxial La0.7Sr0.3MnO3 thin films as a function of oxygen partial pressure
journal, October 2008

  • Fister, Tim T.; Fong, Dillon D.; Eastman, Jeffrey A.
  • Applied Physics Letters, Vol. 93, Issue 15
  • DOI: 10.1063/1.2987731

Characterization of surface defects formation in strontium titanate(100)
journal, May 1994


Optical absorption and emission near the band edge of SrO
journal, December 1979


Investigation of Cathode Behavior of Model Thin-Film SrTi[sub 1−x]Fe[sub x]O[sub 3−δ] (x=0.35 and 0.5) Mixed Ionic-Electronic Conducting Electrodes
journal, January 2008

  • Jung, WooChul; Tuller, Harry L.
  • Journal of The Electrochemical Society, Vol. 155, Issue 11
  • DOI: 10.1149/1.2976212

Investigation of surface Sr segregation in model thin film solid oxidefuel cell perovskite electrodes
journal, January 2012

  • Jung, WooChul; Tuller, Harry L.
  • Energy Environ. Sci., Vol. 5, Issue 1
  • DOI: 10.1039/C1EE02762J

X-ray photoelectron spectroscopic and ion scattering study of the SrTiO3(001) surface
journal, February 2001


Impedance study of SrTi1−xFexO3−δ (x=0.05 to 0.80) mixed ionic-electronic conducting model cathode
journal, June 2009


Surface segregation and restructuring of colossal-magnetoresistant manganese perovskites La 0.65 Sr 0.35 MnO 3
journal, December 2000


Oxygen vacancies in transition metal and rare earth oxides: Current state of understanding and remaining challenges
journal, June 2007

  • Ganduglia-Pirovano, M. Verónica; Hofmann, Alexander; Sauer, Joachim
  • Surface Science Reports, Vol. 62, Issue 6
  • DOI: 10.1016/j.surfrep.2007.03.002

The surface phases of the La0.65Pb0.35MnO3 manganese perovskite surface
journal, June 2002


Enhanced oxygen reduction activity on surface-decorated perovskite thin films for solid oxide fuel cells
journal, January 2011

  • Mutoro, Eva; Crumlin, Ethan J.; Biegalski, Michael D.
  • Energy & Environmental Science, Vol. 4, Issue 9, p. 3689-3696
  • DOI: 10.1039/c1ee01245b

Surface core-level shifts of barium observed in photoemission of vacuum-fractured BaTiO 3 (100)
journal, April 1993


Chemical Heterogeneities on La 0.6 Sr 0.4 CoO 3−δ Thin Films—Correlations to Cathode Surface Activity and Stability
journal, March 2012

  • Cai, Zhuhua; Kubicek, Markus; Fleig, Jürgen
  • Chemistry of Materials, Vol. 24, Issue 6
  • DOI: 10.1021/cm203501u

New Insights into the Strain Coupling to Surface Chemistry, Electronic Structure, and Reactivity of La 0.7 Sr 0.3 MnO 3
journal, March 2011

  • Jalili, Helia; Han, Jeong Woo; Kuru, Yener
  • The Journal of Physical Chemistry Letters, Vol. 2, Issue 7
  • DOI: 10.1021/jz200160b

Oxygen transport in La1−xSrxMn1−yCoyO3±δ perovskites
journal, November 1999


Systematic XPS studies of metal oxides, hydroxides and peroxides
journal, January 2000

  • Dupin, Jean-Charles; Gonbeau, Danielle; Vinatier, Philippe
  • Physical Chemistry Chemical Physics, Vol. 2, Issue 6
  • DOI: 10.1039/a908800h

Oxygen incorporation into Fe-doped SrTiO3: Mechanistic interpretation of the surface reaction
journal, August 2002

  • Merkle, Rotraut; Maier, Joachim
  • Physical Chemistry Chemical Physics, Vol. 4, Issue 17
  • DOI: 10.1039/b204032h

A universal empirical expression for the isotope surface exchange coefficients (k*) of acceptor-doped perovskite and fluorite oxides
journal, January 2006

  • De Souza, R. A.
  • Physical Chemistry Chemical Physics, Vol. 8, Issue 7
  • DOI: 10.1039/b511702j

Reaction of water with MgO(100) surfaces. Part I:
journal, September 1998


Electronic structure of La0.7Sr0.3MnO3 thin films for hybrid organic/inorganic spintronics applications
journal, December 2003

  • de Jong, M. P.; Dediu, V. A.; Taliani, C.
  • Journal of Applied Physics, Vol. 94, Issue 11
  • DOI: 10.1063/1.1625081

Stress relaxation of La1/2Sr1/2MnO3 and La2/3Ca1/3MnO3 at solid oxide fuel cell interfaces
journal, January 2008


Optical reflectivity and Raman spectra of Sr 2 FeO 4 under pressure
journal, October 1994


A New Model Describing Solid Oxide Fuel Cell Cathode Kinetics: Model Thin Film SrTi1-xFexO3-δ Mixed Conducting Oxides-a Case Study
journal, September 2011


Materials for fuel-cell technologies
journal, November 2001

  • Steele, Brian C. H.; Heinzel, Angelika
  • Nature, Vol. 414, Issue 6861, p. 345-352
  • DOI: 10.1038/35104620

Why gold is the noblest of all the metals
journal, July 1995


Ab initio study of Sr Fe x Ti 1 x O 3 : Jahn-Teller distortion and electronic structure
journal, February 2008


Electron tunneling characteristics on La0.7Sr0.3MnO3 thin-film surfaces at high temperature
journal, August 2009

  • Katsiev, Khabiboulakh; Yildiz, Bilge; Balasubramaniam, Kavaipatti
  • Applied Physics Letters, Vol. 95, Issue 9
  • DOI: 10.1063/1.3204022

Restructuring of the surface region in SrTiO 3
journal, December 1996

  • Szot, K.; Speier, W.; Herion, J.
  • Applied Physics A: Materials Science & Processing, Vol. 64, Issue 1
  • DOI: 10.1007/s003390050443

Scanning tunneling spectroscopy analysis with a triangular inverse transfer matrix and its application to reduced SrTiO3 (110) surface
journal, March 2001


Atomistic simulations of surface segregation of defects in solid oxide electrolytes
journal, April 2010


Factors Governing Oxygen Reduction in Solid Oxide Fuel Cell Cathodes
journal, October 2004


Electronic structure and band gap of the negative charge-transfer material Sr3Fe2O7
journal, January 2004


Surface Electronic Structure Transitions at High Temperature on Perovskite Oxides: The Case of Strained La 0.8 Sr 0.2 CoO 3 Thin Films
journal, November 2011

  • Cai, Zhuhua; Kuru, Yener; Han, Jeong Woo
  • Journal of the American Chemical Society, Vol. 133, Issue 44
  • DOI: 10.1021/ja2059445

Materials for Solid Oxide Fuel Cells
journal, February 2010


Island formation on 0.1 at.% La-doped SrTiO3(100) at elevated temperatures under reducing conditions
journal, January 2003


Oxygen diffusion in solid oxide fuel cell cathode and electrolyte materials: mechanistic insights from atomistic simulations
journal, January 2011

  • Chroneos, Alexander; Yildiz, Bilge; Tarancón, Albert
  • Energy & Environmental Science, Vol. 4, Issue 8
  • DOI: 10.1039/c0ee00717j

Prediction of solid oxide fuel cell cathode activity with first-principles descriptors
journal, January 2011

  • Lee, Yueh-Lin; Kleis, Jesper; Rossmeisl, Jan
  • Energy & Environmental Science, Vol. 4, Issue 10
  • DOI: 10.1039/c1ee02032c

Surface Structure of Oxygen Annealed Donor Doped SrTiO3(100) Single Crystals Studied with Spectroscopic Electron Microscopy
journal, January 2002

  • Wei, Han; Maus-Friedrichs, W.; Lilienkamp, G.
  • Journal of Electroceramics, Vol. 8, Issue 3, p. 221-228
  • DOI: 10.1023/A:1020850101504

Design principles for oxygen-reduction activity on perovskite oxide catalysts for fuel cells and metal–air batteries
journal, June 2011

  • Suntivich, Jin; Gasteiger, Hubert A.; Yabuuchi, Naoaki
  • Nature Chemistry, Vol. 3, Issue 7, p. 546-550
  • DOI: 10.1038/nchem.1069

Enhancement of oxygen surface kinetics of SrTiO3 by alkaline earth metal oxides
journal, October 2006


Effects of thickness on the cation segregation in epitaxial (001) and (110) La2/3Ca1/3MnO3 thin films
journal, August 2009

  • Estradé, S.; Rebled, J. M.; Arbiol, J.
  • Applied Physics Letters, Vol. 95, Issue 7
  • DOI: 10.1063/1.3211130

Surface electronic phase transition in colossal magnetoresistive manganese perovskites: La0.65Sr0.35MnO3
journal, July 2000

  • Dulli, Hani; Plummer, E. W.; Dowben, P. A.
  • Applied Physics Letters, Vol. 77, Issue 4
  • DOI: 10.1063/1.127047

Electronic structure of SrFe 4 + O 3 and related Fe perovskite oxides
journal, January 1992


Electronic Structure, Defect Chemistry, and Transport Properties of SrTi 1 - x Fe x O 3 - y Solid Solutions
journal, August 2006

  • Rothschild, Avner; Menesklou, Wolfgang; Tuller, Harry L.
  • Chemistry of Materials, Vol. 18, Issue 16
  • DOI: 10.1021/cm052803x

A Nano-Micro Engineering Nanofiber for Electromagnetic Absorber, Green Shielding and Sensor
journal, November 2020


Works referencing / citing this record:

Formation and Movement of Cationic Defects During Forming and Resistive Switching in SrTiO 3 Thin Film Devices
journal, May 2015

  • Lenser, Christian; Koehl, Annemarie; Slipukhina, Ivetta
  • Advanced Functional Materials, Vol. 25, Issue 40
  • DOI: 10.1002/adfm.201500851

How Does Moisture Affect the Physical Property of Memristance for Anionic-Electronic Resistive Switching Memories?
journal, July 2015

  • Messerschmitt, Felix; Kubicek, Markus; Rupp, Jennifer L. M.
  • Advanced Functional Materials, Vol. 25, Issue 32
  • DOI: 10.1002/adfm.201501517

Improving the Activity for Oxygen Evolution Reaction by Tailoring Oxygen Defects in Double Perovskite Oxides
journal, June 2019

  • Zhu, Yunmin; Zhang, Lei; Zhao, Bote
  • Advanced Functional Materials, Vol. 29, Issue 34
  • DOI: 10.1002/adfm.201901783

Effect of Cationic Interface Defects on Band Alignment and Contact Resistance in Metal/Oxide Heterojunctions
journal, November 2019

  • Andrä, Michael; Funck, Carsten; Raab, Nicolas
  • Advanced Electronic Materials, Vol. 6, Issue 1
  • DOI: 10.1002/aelm.201900808

Oxygen Ion Diffusion and Surface Exchange Properties of the α- and δ-phases of Bi 2 O 3
journal, March 2014

  • Bayliss, Ryan D.; Cook, Stuart N.; Kotsantonis, Sakis
  • Advanced Energy Materials, Vol. 4, Issue 10
  • DOI: 10.1002/aenm.201301575

Segregation Induced Self-Assembly of Highly Active Perovskite for Rapid Oxygen Reduction Reaction
journal, September 2018

  • Li, Yifeng; Zhang, Wenqiang; Wu, Tong
  • Advanced Energy Materials, Vol. 8, Issue 29
  • DOI: 10.1002/aenm.201801893

Enhancement of the SrTiO 3 Surface Reactivity by Exposure to Electric Fields
journal, May 2019


Chemomechanics of ionically conductive ceramics for electrical energy conversion and storage
journal, January 2014


Nano-socketed nickel particles with enhanced coking resistance grown in situ by redox exsolution
journal, September 2015

  • Neagu, Dragos; Oh, Tae-Sik; Miller, David N.
  • Nature Communications, Vol. 6, Issue 1
  • DOI: 10.1038/ncomms9120

Evolution of the electrochemical interface in high-temperature fuel cells and electrolysers
journal, January 2016

  • Irvine, John T. S.; Neagu, Dragos; Verbraeken, Maarten C.
  • Nature Energy, Vol. 1, Issue 1
  • DOI: 10.1038/nenergy.2015.14

Improved chemical and electrochemical stability of perovskite oxides with less reducible cations at the surface
journal, June 2016

  • Tsvetkov, Nikolai; Lu, Qiyang; Sun, Lixin
  • Nature Materials, Vol. 15, Issue 9
  • DOI: 10.1038/nmat4659

Real-time impedance monitoring of oxygen reduction during surface modification of thin film cathodes
journal, March 2017

  • Rupp, Ghislain M.; Opitz, Alexander K.; Nenning, Andreas
  • Nature Materials, Vol. 16, Issue 6
  • DOI: 10.1038/nmat4879

Influence of surface atomic structure demonstrated on oxygen incorporation mechanism at a model perovskite oxide
journal, September 2018


Bismuth and chromium co-doped strontium titanates and their photocatalytic properties under visible light irradiation
journal, January 2015

  • Lv, Meilin; Xie, Yinghao; Wang, Yawei
  • Physical Chemistry Chemical Physics, Vol. 17, Issue 39
  • DOI: 10.1039/c5cp03889h

Suppressing cation segregation on lanthanum-based perovskite oxides to enhance the stability of solid oxide fuel cell cathodes
journal, January 2016

  • Kwon, Hyunguk; Lee, Wonyoung; Han, Jeong Woo
  • RSC Advances, Vol. 6, Issue 74
  • DOI: 10.1039/c6ra15253h

Interfacial stability and ionic conductivity enhanced by dopant segregation in eutectic ceramics: the role of Gd segregation in doped CeO 2 /CoO and CeO 2 /NiO interfaces
journal, January 2020

  • Orera, Alodia; Wang, Funing; Ferreiro-Vila, Elías
  • Journal of Materials Chemistry A, Vol. 8, Issue 5
  • DOI: 10.1039/c9ta12315f

Electronic properties and surface reactivity of SrO-terminated SrTiO 3 and SrO-terminated iron-doped SrTiO 3
journal, March 2018

  • Staykov, Aleksandar; Tellez, Helena; Druce, John
  • Science and Technology of Advanced Materials, Vol. 19, Issue 1
  • DOI: 10.1080/14686996.2018.1440136

Can solute segregation in ceramic materials be reduced by lattice strain?
journal, October 2017

  • Harrington, George F.; Skinner, Stephen J.; Kilner, John A.
  • Journal of the American Ceramic Society, Vol. 101, Issue 3
  • DOI: 10.1111/jace.15259

The Electrochemical Properties of Sr(Ti,Fe)O 3-δ for Anodes in Solid Oxide Fuel Cells
journal, January 2017

  • Nenning, Andreas; Volgger, Lukas; Miller, Elizabeth
  • Journal of The Electrochemical Society, Vol. 164, Issue 4
  • DOI: 10.1149/2.1271704jes

Hydrogen Oxidation Mechanisms on Perovskite Solid Oxide Fuel Cell Anodes
journal, January 2016

  • Zhu, Tenglong; Fowler, Daniel E.; Poeppelmeier, Kenneth R.
  • Journal of The Electrochemical Society, Vol. 163, Issue 8
  • DOI: 10.1149/2.1321608jes

Oxygen Ion Diffusion and Surface Exchange Properties of the α-and δ-phases of Bi 2 O 3
journal, November 2014

  • Bayliss, Ryan D.; Cook, Stuart N.; Kotsantonis, Sakis
  • Advanced Energy Materials, Vol. 4, Issue 16
  • DOI: 10.1002/aenm.201401815

Effect of Cationic Interface Defects on Band Alignment and Contact Resistance in Metal/Oxide Heterojunctions
text, January 2019


The Electrochemical Properties of Sr(Ti,Fe)O3-delta for Anodes in Solid Oxide Fuel Cells
text, January 2017