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Appl. Sci. 2019, 9(5), 1030; https://doi.org/10.3390/app9051030

北京pk10全天稳定计划: Controlling the Oxygen Electrocatalysis on Perovskite and Layered Oxide Thin Films for Solid Oxide Fuel Cell Cathodes

1
Department of Mechanical Engineering, University of South Carolina, Columbia, SC 29208, USA
2
Energy Lab, Samsung Advanced Institute of Technology, Suwon, Gyeonggi-do 16678, Korea
*
Author to whom correspondence should be addressed.
Received: 13 February 2019 / Revised: 5 March 2019 / Accepted: 6 March 2019 / Published: 12 March 2019
(This article belongs to the Special Issue Progress in Solid-Oxide Fuel Cell Technology)
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Figure 1
<p>Schematic of possible elementary reaction steps during oxygen reduction reaction (ORR) and possible pathways for two different classes of cathode materials; (<bold>a</bold>) pure electronic conductor and (<bold>b</bold>) mixed ionic and electronic conducting (MIEC) cathodes.</p> ">
Figure 2
<p>Schematic crystal structure of ABO<sub>3</sub> perovskite oxides, where A and B are a rare earth and transition metal atom.</p> ">
Figure 3
<p>Arrhenius plots of surface exchange coefficients (<italic>k</italic>*) for epitaxial La<sub>1?x</sub>Sr<sub>x</sub>CoO<sub>3?δ</sub> thin films. (<bold>a</bold>) Effect of thickness difference on <italic>k</italic>* for La<sub>0.6</sub>Sr<sub>0.4</sub>CoO<sub>3?δ</sub> [<xref ref-type="bibr" rid="B96-applsci-09-01030">96</xref>] and of substrate difference (STO and LAO) on <italic>k</italic>* for La<sub>0.8</sub>Sr<sub>0.2</sub>CoO<sub>3?δ</sub> [<xref ref-type="bibr" rid="B64-applsci-09-01030">64</xref>] thin films and La<sub>0.8</sub>Sr<sub>0.2</sub>CoO<sub>3?δ</sub> [<xref ref-type="bibr" rid="B9-applsci-09-01030">9</xref>] polycrystalline samples. (<bold>b</bold>) Effect of Sr substitution on <italic>k</italic>* for La<sub>1?x</sub>Sr<sub>x</sub>CoO<sub>3?δ</sub> (x = 0, 0.2 and 0.4, [<xref ref-type="bibr" rid="B64-applsci-09-01030">64</xref>,<xref ref-type="bibr" rid="B95-applsci-09-01030">95</xref>,<xref ref-type="bibr" rid="B96-applsci-09-01030">96</xref>]) thin films and La<sub>0.8</sub>Sr<sub>0.2</sub>CoO<sub>3?δ</sub> [<xref ref-type="bibr" rid="B9-applsci-09-01030">9</xref>] polycrystalline oxides.</p> ">
Figure 4
<p>(<bold>a</bold>) Schematic electronic structure plots to illustrate the correlation of the ORR energetics vs. the O p-band center based on the rigid band model. Reprinted from [<xref ref-type="bibr" rid="B100-applsci-09-01030">100</xref>] with permission of The Royal Society of Chemistry. (<bold>b</bold>) DFT calculations for the oxygen 2p-band center with respect to the Fermi level as a function of strain in LSCO films. The calculated oxygen 2p-band centers are averaged over LSCO films with five different Sr orderings. Reprinted from [<xref ref-type="bibr" rid="B96-applsci-09-01030">96</xref>] with permission of The American Chemical Society.</p> ">
Figure 5
<p>Arrhenius plots of surface exchange coefficients (<italic>k</italic>*) for La<sub>1?x</sub>Sr<sub>x</sub>Co<sub>1?y</sub>Fe<sub>y</sub>O<sub>3?δ</sub> thin films. (<bold>a</bold>) Effect of strain on <italic>k</italic>* for La<sub>0.6</sub>Sr<sub>0.4</sub>Co<sub>0.2</sub>Fe<sub>0.8</sub>O<sub>3?δ</sub> [<xref ref-type="bibr" rid="B117-applsci-09-01030">117</xref>] and La<sub>0.6</sub>Sr<sub>0.4</sub>Co<sub>0.2</sub>Fe<sub>0.8</sub>O<sub>3?δ</sub> [<xref ref-type="bibr" rid="B118-applsci-09-01030">118</xref>] films and La<sub>0.6</sub>Sr<sub>0.4</sub>Co<sub>0.2</sub>Fe<sub>0.8</sub>O<sub>3?δ</sub> (Ref. [<xref ref-type="bibr" rid="B119-applsci-09-01030">119</xref>]) polycrystalline samples. (<bold>b</bold>) Effect of Sr substitution on <italic>k</italic>* for La<sub>1?x</sub>Sr<sub>x</sub>Co<sub>1?y</sub>Fe<sub>y</sub>O<sub>3?δ</sub> (red [<xref ref-type="bibr" rid="B117-applsci-09-01030">117</xref>], black [<xref ref-type="bibr" rid="B47-applsci-09-01030">47</xref>] and blue [<xref ref-type="bibr" rid="B114-applsci-09-01030">114</xref>]) films and La<sub>0.6</sub>Sr<sub>0.4</sub>Co<sub>0.2</sub>Fe<sub>0.8</sub>O<sub>3?δ</sub> [<xref ref-type="bibr" rid="B119-applsci-09-01030">119</xref>] polycrystalline oxides.</p> ">
Figure 6
<p>Schematic crystal structure of RP oxides, where A and B are a rare earth and transition metal atom.</p> ">
Figure 7
<p>Arrhenius plots of surface exchange coefficients (<italic>k</italic>*) for A<sub>2</sub>NiO<sub>4+δ</sub> (A = La and Nd): (<bold>a</bold>) Tensile (Tens.) and compressive (Comp.) strained (001)-oriented La<sub>2</sub>NiO<sub>4+δ</sub> films [<xref ref-type="bibr" rid="B61-applsci-09-01030">61</xref>] and tensile, zero, and compressive strained (100)-oriented Nd<sub>2</sub>NiO<sub>4+δ</sub> thin films [<xref ref-type="bibr" rid="B135-applsci-09-01030">135</xref>]; (<bold>b</bold>) (001)- and (100)-oriented La<sub>2</sub>NiO<sub>4+δ</sub> [<xref ref-type="bibr" rid="B61-applsci-09-01030">61</xref>,<xref ref-type="bibr" rid="B63-applsci-09-01030">63</xref>] thin films with various thickness and substrates.</p> ">
Figure 8
<p>Oxygen surface exchange coefficients (<italic>k</italic>*) of La<sub>2</sub>CuO<sub>4</sub> (light blue), LaSrCoO<sub>4</sub> (green), La<sub>1.85</sub>Sr<sub>0.15</sub>CuO<sub>4</sub> (blue), La<sub>1.6</sub>Sr<sub>0.4</sub>CuO<sub>4</sub> (deep blue), and LaSrNiO<sub>4</sub> (red) films with (001) orientations measured at 550 °C versus the computed DFT bulk O 2p-band centers (relative to the Fermi level, E<sub>Fermi</sub>). The gray dashed lines represent the correlation between experimental oxygen surface-exchange coefficients and the computed bulk O 2p-band centers for a series of SOFC perovskites. Reprinted from [<xref ref-type="bibr" rid="B126-applsci-09-01030">126</xref>] with permission of The American Chemical Society.</p> ">
Figure 9
<p>Arrhenius plots of surface exchange coefficients (<italic>k</italic>*) for different RP oxides: (<bold>a</bold>) <italic>k</italic>* along c-direction in La<sub>2-<italic>x</italic></sub>Sr<italic><sub>x</sub></italic>MO<sub>4</sub> (M = Cu, Co, Ni, [<xref ref-type="bibr" rid="B126-applsci-09-01030">126</xref>,<xref ref-type="bibr" rid="B133-applsci-09-01030">133</xref>,<xref ref-type="bibr" rid="B135-applsci-09-01030">135</xref>,<xref ref-type="bibr" rid="B144-applsci-09-01030">144</xref>]); and (<bold>b</bold>) <italic>k</italic>* along a-b plane in A<sub>2-<italic>x</italic></sub>Sr<italic><sub>x</sub></italic>MO<sub>4</sub> (A = Sr, La, Nd and M = Co, Ni, [<xref ref-type="bibr" rid="B61-applsci-09-01030">61</xref>,<xref ref-type="bibr" rid="B65-applsci-09-01030">65</xref>,<xref ref-type="bibr" rid="B128-applsci-09-01030">128</xref>,<xref ref-type="bibr" rid="B133-applsci-09-01030">133</xref>,<xref ref-type="bibr" rid="B135-applsci-09-01030">135</xref>,<xref ref-type="bibr" rid="B144-applsci-09-01030">144</xref>]) thin films.</p> ">
Figure 10
<p>(<bold>a</bold>) The calculated Sr/La substitution energies in the bulk LSC<sub>214</sub>, LSC<sub>113</sub>, and LSCF<sub>113</sub> (all relative to that of LSC<sub>113</sub>, which is set to 0). (<bold>b</bold>) The heterostructured interface model used in the DFT simulations and the results of Sr/La substitution energies. The elements are represented as: La/Sr (dark blue), Fe/Co (light blue, center of the octahedra), and O (red). Reprinted from [<xref ref-type="bibr" rid="B86-applsci-09-01030">86</xref>] with permission of The Royal Society of Chemistry.</p> ">
Figure 11
<p>Arrhenius plots of surface exchange coefficients (<italic>k</italic>*) for various heterostructure oxide thin films. Effect of heterostructure interfaces on <italic>k</italic>* for La<sub>0.6</sub>Sr<sub>0.4</sub>CoO<sub>3?δ</sub>/(LaSr)<sub>2</sub>CoO<sub>4±δ</sub> [<xref ref-type="bibr" rid="B150-applsci-09-01030">150</xref>], La<sub>0.625</sub>Sr<sub>0.375</sub>Fe<sub>0.75</sub>Co<sub>0.25</sub>O<sub>3?δ</sub>/(LaSr)<sub>2</sub>CoO<sub>4±δ</sub> [<xref ref-type="bibr" rid="B86-applsci-09-01030">86</xref>], La<sub>0.8</sub>Sr<sub>0.2</sub>CoO<sub>3?δ</sub>/La<sub>0.8</sub>Sr<sub>0.2</sub>MnO<sub>3?δ</sub> [<xref ref-type="bibr" rid="B76-applsci-09-01030">76</xref>], La<sub>0.8</sub>Sr<sub>0.2</sub>CoO<sub>3?δ</sub>/(LaSr)<sub>2</sub>CoO<sub>4±δ</sub> [<xref ref-type="bibr" rid="B148-applsci-09-01030">148</xref>] and La<sub>0.6</sub>Sr<sub>0.4</sub>Fe<sub>0.8</sub>Co<sub>0.2</sub>O<sub>3?δ</sub>/La<sub>0.4</sub>Sr<sub>0.6</sub>CoO<sub>3?δ</sub>:(LaSr)<sub>2</sub>CoO<sub>4±δ</sub> [<xref ref-type="bibr" rid="B66-applsci-09-01030">66</xref>].</p> ">

Abstract

Achieving the fast oxygen reduction reaction (ORR) kinetics at the cathode of solid oxide fuel cells (SOFCs) is indispensable to enhance the efficiency of SOFCs at intermediate temperatures. Mixed ionic and electronic conducting (MIEC) oxides such as ABO3 perovskites and Ruddlesden-Popper (RP) oxides (A2BO4) have been widely used as promising cathode materials owing to their attractive physicochemical properties. In particular, oxides in forms of thin films and heterostructures have enabled significant enhancement in the ORR activity. Therefore, we aim to give a comprehensive overview on the recent development of thin film cathodes of SOFCs. We discuss important advances in ABO3 and RP oxide thin film cathodes for SOFCs. Our attention is also paid to the influence of oxide heterostructure interfaces on the ORR activity of SOFC cathodes. View Full-Text
Keywords: solid oxide fuel cells; cathodes; oxygen reductions reaction; oxygen surface exchange kinetics; oxide thin films; ABO3 oxides; Ruddlesden-Popper oxides; heterostructure oxide thin films; strain engineering; oxide interfaces solid oxide fuel cells; cathodes; oxygen reductions reaction; oxygen surface exchange kinetics; oxide thin films; ABO3 oxides; Ruddlesden-Popper oxides; heterostructure oxide thin films; strain engineering; oxide interfaces
Figures

秒速赛车是哪里的开奖 www.0dv0k.cn Figure 1

Figure 1
<p>Schematic of possible elementary reaction steps during oxygen reduction reaction (ORR) and possible pathways for two different classes of cathode materials; (<bold>a</bold>) pure electronic conductor and (<bold>b</bold>) mixed ionic and electronic conducting (MIEC) cathodes.</p> ">
Figure 2
<p>Schematic crystal structure of ABO<sub>3</sub> perovskite oxides, where A and B are a rare earth and transition metal atom.</p> ">
Figure 3
<p>Arrhenius plots of surface exchange coefficients (<italic>k</italic>*) for epitaxial La<sub>1?x</sub>Sr<sub>x</sub>CoO<sub>3?δ</sub> thin films. (<bold>a</bold>) Effect of thickness difference on <italic>k</italic>* for La<sub>0.6</sub>Sr<sub>0.4</sub>CoO<sub>3?δ</sub> [<xref ref-type="bibr" rid="B96-applsci-09-01030">96</xref>] and of substrate difference (STO and LAO) on <italic>k</italic>* for La<sub>0.8</sub>Sr<sub>0.2</sub>CoO<sub>3?δ</sub> [<xref ref-type="bibr" rid="B64-applsci-09-01030">64</xref>] thin films and La<sub>0.8</sub>Sr<sub>0.2</sub>CoO<sub>3?δ</sub> [<xref ref-type="bibr" rid="B9-applsci-09-01030">9</xref>] polycrystalline samples. (<bold>b</bold>) Effect of Sr substitution on <italic>k</italic>* for La<sub>1?x</sub>Sr<sub>x</sub>CoO<sub>3?δ</sub> (x = 0, 0.2 and 0.4, [<xref ref-type="bibr" rid="B64-applsci-09-01030">64</xref>,<xref ref-type="bibr" rid="B95-applsci-09-01030">95</xref>,<xref ref-type="bibr" rid="B96-applsci-09-01030">96</xref>]) thin films and La<sub>0.8</sub>Sr<sub>0.2</sub>CoO<sub>3?δ</sub> [<xref ref-type="bibr" rid="B9-applsci-09-01030">9</xref>] polycrystalline oxides.</p> ">
Figure 4
<p>(<bold>a</bold>) Schematic electronic structure plots to illustrate the correlation of the ORR energetics vs. the O p-band center based on the rigid band model. Reprinted from [<xref ref-type="bibr" rid="B100-applsci-09-01030">100</xref>] with permission of The Royal Society of Chemistry. (<bold>b</bold>) DFT calculations for the oxygen 2p-band center with respect to the Fermi level as a function of strain in LSCO films. The calculated oxygen 2p-band centers are averaged over LSCO films with five different Sr orderings. Reprinted from [<xref ref-type="bibr" rid="B96-applsci-09-01030">96</xref>] with permission of The American Chemical Society.</p> ">
Figure 5
<p>Arrhenius plots of surface exchange coefficients (<italic>k</italic>*) for La<sub>1?x</sub>Sr<sub>x</sub>Co<sub>1?y</sub>Fe<sub>y</sub>O<sub>3?δ</sub> thin films. (<bold>a</bold>) Effect of strain on <italic>k</italic>* for La<sub>0.6</sub>Sr<sub>0.4</sub>Co<sub>0.2</sub>Fe<sub>0.8</sub>O<sub>3?δ</sub> [<xref ref-type="bibr" rid="B117-applsci-09-01030">117</xref>] and La<sub>0.6</sub>Sr<sub>0.4</sub>Co<sub>0.2</sub>Fe<sub>0.8</sub>O<sub>3?δ</sub> [<xref ref-type="bibr" rid="B118-applsci-09-01030">118</xref>] films and La<sub>0.6</sub>Sr<sub>0.4</sub>Co<sub>0.2</sub>Fe<sub>0.8</sub>O<sub>3?δ</sub> (Ref. [<xref ref-type="bibr" rid="B119-applsci-09-01030">119</xref>]) polycrystalline samples. (<bold>b</bold>) Effect of Sr substitution on <italic>k</italic>* for La<sub>1?x</sub>Sr<sub>x</sub>Co<sub>1?y</sub>Fe<sub>y</sub>O<sub>3?δ</sub> (red [<xref ref-type="bibr" rid="B117-applsci-09-01030">117</xref>], black [<xref ref-type="bibr" rid="B47-applsci-09-01030">47</xref>] and blue [<xref ref-type="bibr" rid="B114-applsci-09-01030">114</xref>]) films and La<sub>0.6</sub>Sr<sub>0.4</sub>Co<sub>0.2</sub>Fe<sub>0.8</sub>O<sub>3?δ</sub> [<xref ref-type="bibr" rid="B119-applsci-09-01030">119</xref>] polycrystalline oxides.</p> ">
Figure 6
<p>Schematic crystal structure of RP oxides, where A and B are a rare earth and transition metal atom.</p> ">
Figure 7
<p>Arrhenius plots of surface exchange coefficients (<italic>k</italic>*) for A<sub>2</sub>NiO<sub>4+δ</sub> (A = La and Nd): (<bold>a</bold>) Tensile (Tens.) and compressive (Comp.) strained (001)-oriented La<sub>2</sub>NiO<sub>4+δ</sub> films [<xref ref-type="bibr" rid="B61-applsci-09-01030">61</xref>] and tensile, zero, and compressive strained (100)-oriented Nd<sub>2</sub>NiO<sub>4+δ</sub> thin films [<xref ref-type="bibr" rid="B135-applsci-09-01030">135</xref>]; (<bold>b</bold>) (001)- and (100)-oriented La<sub>2</sub>NiO<sub>4+δ</sub> [<xref ref-type="bibr" rid="B61-applsci-09-01030">61</xref>,<xref ref-type="bibr" rid="B63-applsci-09-01030">63</xref>] thin films with various thickness and substrates.</p> ">
Figure 8
<p>Oxygen surface exchange coefficients (<italic>k</italic>*) of La<sub>2</sub>CuO<sub>4</sub> (light blue), LaSrCoO<sub>4</sub> (green), La<sub>1.85</sub>Sr<sub>0.15</sub>CuO<sub>4</sub> (blue), La<sub>1.6</sub>Sr<sub>0.4</sub>CuO<sub>4</sub> (deep blue), and LaSrNiO<sub>4</sub> (red) films with (001) orientations measured at 550 °C versus the computed DFT bulk O 2p-band centers (relative to the Fermi level, E<sub>Fermi</sub>). The gray dashed lines represent the correlation between experimental oxygen surface-exchange coefficients and the computed bulk O 2p-band centers for a series of SOFC perovskites. Reprinted from [<xref ref-type="bibr" rid="B126-applsci-09-01030">126</xref>] with permission of The American Chemical Society.</p> ">
Figure 9
<p>Arrhenius plots of surface exchange coefficients (<italic>k</italic>*) for different RP oxides: (<bold>a</bold>) <italic>k</italic>* along c-direction in La<sub>2-<italic>x</italic></sub>Sr<italic><sub>x</sub></italic>MO<sub>4</sub> (M = Cu, Co, Ni, [<xref ref-type="bibr" rid="B126-applsci-09-01030">126</xref>,<xref ref-type="bibr" rid="B133-applsci-09-01030">133</xref>,<xref ref-type="bibr" rid="B135-applsci-09-01030">135</xref>,<xref ref-type="bibr" rid="B144-applsci-09-01030">144</xref>]); and (<bold>b</bold>) <italic>k</italic>* along a-b plane in A<sub>2-<italic>x</italic></sub>Sr<italic><sub>x</sub></italic>MO<sub>4</sub> (A = Sr, La, Nd and M = Co, Ni, [<xref ref-type="bibr" rid="B61-applsci-09-01030">61</xref>,<xref ref-type="bibr" rid="B65-applsci-09-01030">65</xref>,<xref ref-type="bibr" rid="B128-applsci-09-01030">128</xref>,<xref ref-type="bibr" rid="B133-applsci-09-01030">133</xref>,<xref ref-type="bibr" rid="B135-applsci-09-01030">135</xref>,<xref ref-type="bibr" rid="B144-applsci-09-01030">144</xref>]) thin films.</p> ">
Figure 10
<p>(<bold>a</bold>) The calculated Sr/La substitution energies in the bulk LSC<sub>214</sub>, LSC<sub>113</sub>, and LSCF<sub>113</sub> (all relative to that of LSC<sub>113</sub>, which is set to 0). (<bold>b</bold>) The heterostructured interface model used in the DFT simulations and the results of Sr/La substitution energies. The elements are represented as: La/Sr (dark blue), Fe/Co (light blue, center of the octahedra), and O (red). Reprinted from [<xref ref-type="bibr" rid="B86-applsci-09-01030">86</xref>] with permission of The Royal Society of Chemistry.</p> ">
Figure 11
<p>Arrhenius plots of surface exchange coefficients (<italic>k</italic>*) for various heterostructure oxide thin films. Effect of heterostructure interfaces on <italic>k</italic>* for La<sub>0.6</sub>Sr<sub>0.4</sub>CoO<sub>3?δ</sub>/(LaSr)<sub>2</sub>CoO<sub>4±δ</sub> [<xref ref-type="bibr" rid="B150-applsci-09-01030">150</xref>], La<sub>0.625</sub>Sr<sub>0.375</sub>Fe<sub>0.75</sub>Co<sub>0.25</sub>O<sub>3?δ</sub>/(LaSr)<sub>2</sub>CoO<sub>4±δ</sub> [<xref ref-type="bibr" rid="B86-applsci-09-01030">86</xref>], La<sub>0.8</sub>Sr<sub>0.2</sub>CoO<sub>3?δ</sub>/La<sub>0.8</sub>Sr<sub>0.2</sub>MnO<sub>3?δ</sub> [<xref ref-type="bibr" rid="B76-applsci-09-01030">76</xref>], La<sub>0.8</sub>Sr<sub>0.2</sub>CoO<sub>3?δ</sub>/(LaSr)<sub>2</sub>CoO<sub>4±δ</sub> [<xref ref-type="bibr" rid="B148-applsci-09-01030">148</xref>] and La<sub>0.6</sub>Sr<sub>0.4</sub>Fe<sub>0.8</sub>Co<sub>0.2</sub>O<sub>3?δ</sub>/La<sub>0.4</sub>Sr<sub>0.6</sub>CoO<sub>3?δ</sub>:(LaSr)<sub>2</sub>CoO<sub>4±δ</sub> [<xref ref-type="bibr" rid="B66-applsci-09-01030">66</xref>].</p> ">
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Yang, G.; Jung, W.; Ahn, S.-J.; Lee, D. Controlling the Oxygen Electrocatalysis on Perovskite and Layered Oxide Thin Films for Solid Oxide Fuel Cell Cathodes. Appl. Sci. 2019, 9, 1030.

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