Determination of Fe oxidation states in the B-site ordered perovskite-type Ba2Ca0.67Fe0.33NbO6-δ at the surface (nano-scale) and bulk by variable temperature XPS and TGA and their impact on electrochemical catalysis

Wang Hay Kan; Min Chen; Jong Seong Bae; Bok Hee Kim; Venkataraman Thangadurai

doi:10.1039/c4ta00811a

Determination of Fe oxidation states in the B-site ordered perovskite-type Ba₂Ca_0.67Fe_0.33NbO_6-δ at the surface (nano-scale) and bulk by variable temperature XPS and TGA and their impact on electrochemical catalysis

Wang Hay Kan, Min Chen, Jong Seong Bae, Bok Hee Kim, Venkataraman Thangadurai^*

^*Corresponding author for this work

School of Chemistry

Research output: Contribution to journal › Article › peer-review

Abstract

In this study, we analyzed the surface and bulk valences of Fe in the double perovskite-type Ba₂Ca_0.67Fe_0.33NbO _6-δ by both variable temperature X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA). The concentration of Fe²⁺ near-surface was found to be about 3 times higher than that in the bulk sample. The electrochemical performance of Ba₂Ca _0.67M_0.33NbO_6-δ (M = Mn, Fe and Co) was assessed by ac impedance spectroscopy using a Zr_0.84Y _0.16O_1.92 (YSZ) supported half-cell. The area specific polarization resistances (ASR) of all samples were found to decrease with increasing temperature. We speculate that ASR for H₂ oxidation are correlated with the higher concentrations of low valence Fe²⁺ species near-surface (nano-scale), as demonstrated for Ba₂Ca _0.67Fe_0.33NbO_6-δ. This journal is

Original language	English
Pages (from-to)	8736-8741
Number of pages	6
Journal	Journal of Materials Chemistry A
Volume	2
Issue number	23
DOIs	https://doi.org/10.1039/c4ta00811a
Publication status	Published - 21 Jun 2014

UN SDGs

This output contributes to the following UN Sustainable Development Goals (SDGs)

Access to Document

10.1039/c4ta00811a

Fingerprint

Dive into the research topics of 'Determination of Fe oxidation states in the B-site ordered perovskite-type Ba₂Ca_0.67Fe_0.33NbO_6-δ at the surface (nano-scale) and bulk by variable temperature XPS and TGA and their impact on electrochemical catalysis'. Together they form a unique fingerprint.

Cite this

Kan, W. H., Chen, M., Bae, J. S., Kim, B. H., & Thangadurai, V. (2014). Determination of Fe oxidation states in the B-site ordered perovskite-type Ba₂Ca_0.67Fe_0.33NbO_6-δ at the surface (nano-scale) and bulk by variable temperature XPS and TGA and their impact on electrochemical catalysis. Journal of Materials Chemistry A, 2(23), 8736-8741. https://doi.org/10.1039/c4ta00811a

@article{54903cb5afb542bd9e2863f9e99e4cf7,

title = "Determination of Fe oxidation states in the B-site ordered perovskite-type Ba2Ca0.67Fe0.33NbO6-δ at the surface (nano-scale) and bulk by variable temperature XPS and TGA and their impact on electrochemical catalysis",

abstract = "In this study, we analyzed the surface and bulk valences of Fe in the double perovskite-type Ba2Ca0.67Fe0.33NbO 6-δ by both variable temperature X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA). The concentration of Fe2+ near-surface was found to be about 3 times higher than that in the bulk sample. The electrochemical performance of Ba2Ca 0.67M0.33NbO6-δ (M = Mn, Fe and Co) was assessed by ac impedance spectroscopy using a Zr0.84Y 0.16O1.92 (YSZ) supported half-cell. The area specific polarization resistances (ASR) of all samples were found to decrease with increasing temperature. We speculate that ASR for H2 oxidation are correlated with the higher concentrations of low valence Fe2+ species near-surface (nano-scale), as demonstrated for Ba2Ca 0.67Fe0.33NbO6-δ. This journal is",

author = "Kan, {Wang Hay} and Min Chen and Bae, {Jong Seong} and Kim, {Bok Hee} and Venkataraman Thangadurai",

year = "2014",

month = jun,

day = "21",

doi = "10.1039/c4ta00811a",

language = "English",

volume = "2",

pages = "8736--8741",

journal = "Journal of Materials Chemistry A",

issn = "2050-7488",

publisher = "ROYAL SOC CHEMISTRY",

number = "23",

}

Kan, WH, Chen, M, Bae, JS, Kim, BH & Thangadurai, V 2014, 'Determination of Fe oxidation states in the B-site ordered perovskite-type Ba₂Ca_0.67Fe_0.33NbO_6-δ at the surface (nano-scale) and bulk by variable temperature XPS and TGA and their impact on electrochemical catalysis', Journal of Materials Chemistry A, vol. 2, no. 23, pp. 8736-8741. https://doi.org/10.1039/c4ta00811a

Determination of Fe oxidation states in the B-site ordered perovskite-type Ba₂Ca_0.67Fe_0.33NbO_6-δ at the surface (nano-scale) and bulk by variable temperature XPS and TGA and their impact on electrochemical catalysis. / Kan, Wang Hay; Chen, Min; Bae, Jong Seong et al.
In: Journal of Materials Chemistry A, Vol. 2, No. 23, 21.06.2014, p. 8736-8741.

Research output: Contribution to journal › Article › peer-review

TY - JOUR

T1 - Determination of Fe oxidation states in the B-site ordered perovskite-type Ba2Ca0.67Fe0.33NbO6-δ at the surface (nano-scale) and bulk by variable temperature XPS and TGA and their impact on electrochemical catalysis

AU - Kan, Wang Hay

AU - Chen, Min

AU - Bae, Jong Seong

AU - Kim, Bok Hee

AU - Thangadurai, Venkataraman

PY - 2014/6/21

Y1 - 2014/6/21

N2 - In this study, we analyzed the surface and bulk valences of Fe in the double perovskite-type Ba2Ca0.67Fe0.33NbO 6-δ by both variable temperature X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA). The concentration of Fe2+ near-surface was found to be about 3 times higher than that in the bulk sample. The electrochemical performance of Ba2Ca 0.67M0.33NbO6-δ (M = Mn, Fe and Co) was assessed by ac impedance spectroscopy using a Zr0.84Y 0.16O1.92 (YSZ) supported half-cell. The area specific polarization resistances (ASR) of all samples were found to decrease with increasing temperature. We speculate that ASR for H2 oxidation are correlated with the higher concentrations of low valence Fe2+ species near-surface (nano-scale), as demonstrated for Ba2Ca 0.67Fe0.33NbO6-δ. This journal is

AB - In this study, we analyzed the surface and bulk valences of Fe in the double perovskite-type Ba2Ca0.67Fe0.33NbO 6-δ by both variable temperature X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA). The concentration of Fe2+ near-surface was found to be about 3 times higher than that in the bulk sample. The electrochemical performance of Ba2Ca 0.67M0.33NbO6-δ (M = Mn, Fe and Co) was assessed by ac impedance spectroscopy using a Zr0.84Y 0.16O1.92 (YSZ) supported half-cell. The area specific polarization resistances (ASR) of all samples were found to decrease with increasing temperature. We speculate that ASR for H2 oxidation are correlated with the higher concentrations of low valence Fe2+ species near-surface (nano-scale), as demonstrated for Ba2Ca 0.67Fe0.33NbO6-δ. This journal is

U2 - 10.1039/c4ta00811a

DO - 10.1039/c4ta00811a

M3 - Article

AN - SCOPUS:84901279069

SN - 2050-7488

VL - 2

SP - 8736

EP - 8741

JO - Journal of Materials Chemistry A

JF - Journal of Materials Chemistry A

IS - 23

ER -