Investigation into the effect of Fe-site substitution on the performance of Sr2Fe1.5Mo0.5O6−δ anodes for SOFCs

Feng, Jie; Yang, Guoquan; Dai, Ningning; Wang, Zhenhua; Sun, Wang; Rooney, David; Qiao, Jinshuo; Sun, Kening

doi:10.1039/c4ta03216k

Cited by 77 publications

(24 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In recent decades, extensive efforts have been made to explore Ni-free anodes to resist coking. Among these, perovskite-type oxides Sr 2 Fe 1.5 Mo 0.5 O 6−δ , , Sr 2 MgMoO 6−δ , , PrBaMn 2 O 5+δ , and La 0.6 Sr 0.3 Cr 0.85 Fe 0.15 O 3−δ , have been proven to exhibit varying degrees of improvement in coking resistance and are identified as promising anode candidates for direct hydrocarbon SOFCs. Unfortunately, their catalytic activity is much lower than that of Ni-based anodes.…”

Section: Introductionmentioning

confidence: 99%

Enhanced Anode Performance and Coking Resistance by In Situ Exsolved Multiple-Twinned Co–Fe Nanoparticles for Solid Oxide Fuel Cells

Zhang

Wang

Guan

et al. 2019

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

The broad and large-scale application of solid oxide fuel cells (SOFCs) technology hinges significantly on the development of highly active and robust electrode materials. Here, Ni-free anode materials decorated with metal nanoparticles are synthesized by in situ reduction of Fe-doping Sr 2 CoMo 1−x Fe x O 6−δ (x = 0, 0.05, 0.1) double perovskite oxides under a reducing condition at 850 °C. The exsolved nanoparticles from the Sr 2 CoMo 0.95 Fe 0.05 O 6−δ (SCMF0.05) lattice are Co−Fe alloys with rich multipletwinned defects, significantly enhancing the catalytic activity of the SCMF0.05 anode toward the oxidation of H 2 and CH 4 . The electrolyte-supported single cell with the reuduced SCMF0.05 anode reaches peak power densities as high as 992.9 and 652.3 mW cm −2 in H 2 and CH 4 at 850 °C, respectively, while maintaining superior stability (∼50 h at 700 °C). The reduced SCMF0.05 anode also demonstrates excellent coking resistance in CH 4 , which can be attributed to the increased oxygen vacancies due to Fe doping and the effective catalysis of multiple-twinned Co−Fe alloy nanoparticles for reforming of CH 4 to H 2 and CO. The findings in this work may provide a new insight for the design of highly active and durable anode catalysts in SOFCs.

show abstract

Section: Introductionmentioning

confidence: 99%

Enhanced Anode Performance and Coking Resistance by In Situ Exsolved Multiple-Twinned Co–Fe Nanoparticles for Solid Oxide Fuel Cells

Zhang

Wang

Guan

et al. 2019

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

show abstract

“…Generally, the R p measurement is convoluted and collectively influenced by these factors. The R p values of the symmetrical cells measured by EIS have been commonly reported in the humidified H 2 with P H 2 O = 3% and compared in the literature, ,,− indicating that the influence of the cathodic impedance on the credible analysis of R p is minor and the comparison of measured R p values is rationalized, when P H 2 O is higher than 3%. As shown in Figure b and Table S7, the R p measured in the H 2 –H 2 O mixture atmosphere declines when the P H 2 O grows from 3 to 6% and is retained at the lowest level when P H 2 O rises to 10%.…”

Section: Resultsmentioning

confidence: 67%

Positive Effects of H₂O on the Hydrogen Oxidation Reaction on Sr₂Fe_1.5Mo_0.5O_6−δ-Based Perovskite Anodes for Solid Oxide Fuel Cells

Lee

Yang

et al. 2020

ACS Catal.

View full text Add to dashboard Cite

The steam is commonly supplied with H2 to the anodes of Ni-based solid oxide fuel cells (SOFCs). Humidified H2 is also widely used for emerging perovskite anodes of SOFCs, although the influences of H2O on the hydrogen oxidation reaction (HOR) on their surfaces have not been well understood yet. In this work, the effects of H2O on the HOR on Sr2Fe1.5Mo0.5O6−δ (SF1.5M), La0.5Sr1.5Fe1.5Mo0.5O6−δ (LSFM), and Pr0.5Sr1.5Fe1.5Mo0.5O6−δ (PSFM) were systematically investigated using the electrochemical impedance spectroscopy (EIS) and electrical conductivity relaxation (ECR) methods. The EIS spectra suggested the possible promotional effect of H2O on decreasing the polarization resistance of SF1.5M. The ECR results confirmed that the presence of H2O in H2 can significantly increase the oxygen exchange coefficients of SF1.5M, LSFM, and PSFM. To gain a mechanistic understanding of the role of H2O, the density functional theory-based calculations and thermodynamic modeling were performed to unravel the effect of H2O on the HOR on the SF1.5M (001) surfaces. Benefiting from the increment of the oxygen chemical potential and decrement of the free electron concentration upon increasing humidity, the plateau intermediate state in the HOR energy landscape, the step of H2O plus surface oxygen vacancy formation, is reduced on the SF1.5M (001) BO2 (B = Fe and Mo)-terminated surfaces, when decreasing the slab oxygen nonstoichiometry. Furthermore, by comparing the scenarios of the HOR on the dry and hydrated surfaces, the H2O plus surface oxygen vacancy formation energies are lower in the latter case. These two proposed factors, i.e., (i) change of electron chemical potential upon the change of near-surface δ and (ii) enhanced interaction of surface H species with the hydrated perovskite surfaces, contribute to the promoted HOR in the presence of H2O. This work provides important insights into the effects of H2O on the HOR for SOFCs.

show abstract

“…Figure 2a shows the XPS of Ni 2p for various powder materials. The peaks at the binding energies of 855.2 and 872.6 eV, which can be assigned to the Ni 2+ 2p 3/2 and Ni 2+ 2p 1/2 signals, 43,44 are detected in the oxidized Ni-SVM, demonstrating that nickel in the oxidized Ni-SVM presents as Ni 2+ . The peak at the binding energy of 852.4 eV, which corresponds to metal Ni 0 2p 3/2 , 45,46 is obvious for the reduced Ni-SVM, indicating that nickel in the reduced Ni-SVM presents as the metal state.…”

Section: Resultsmentioning

confidence: 93%

Vanadium-Doped Strontium Molybdate with Exsolved Ni Nanoparticles as Anode Material for Solid Oxide Fuel Cells

Wan

Xie

et al. 2019

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

Vanadium-doped strontium molybdate (SVM) has been investigated as a potential anode material for solid oxide fuel cells due to its high electronic conductivity of about 1000 S cm–1 at 800 °C in reducing atmospheres. In this work, NiO is introduced to SVM with the B-site excess design to induce in situ growth of Ni nanoparticles in the anodic operational conditions. The Ni particles are exsolved from the parent oxide phase as clearly demonstrated with various techniques including X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy. The exsolved Ni nanoparticles significantly boost the electrocatalytic activity toward fuel oxidation reaction, improving the peak power density by 160% from 0.21 to 0.56 W cm–2 at 800 °C when using H2 as the fuel, meanwhile reducing the total interfacial polarization resistance by 56% from 0.81 to 0.36 Ω cm2. The Ni-exsolved SVM anode also shows excellent catalytic activity toward H2S-containing and hydrocarbon fuels, providing peak power densities of 0.43, 0.36, and 0.22 W cm–2 at 800 °C for H2-50 ppm H2S, syngas, and ethanol, respectively. In addition, the cell with the Ni-exsolved SVM anode presents a stable power output, indicating that the Ni-SVM is a potential SOFC anode electrocatalyst for various fuels.

show abstract

Investigation into the effect of Fe-site substitution on the performance of Sr₂Fe_1.5Mo_0.5O_6−δ anodes for SOFCs

Cited by 77 publications

References 35 publications

Enhanced Anode Performance and Coking Resistance by In Situ Exsolved Multiple-Twinned Co–Fe Nanoparticles for Solid Oxide Fuel Cells

Enhanced Anode Performance and Coking Resistance by In Situ Exsolved Multiple-Twinned Co–Fe Nanoparticles for Solid Oxide Fuel Cells

Positive Effects of H₂O on the Hydrogen Oxidation Reaction on Sr₂Fe_1.5Mo_0.5O_6−δ-Based Perovskite Anodes for Solid Oxide Fuel Cells

Vanadium-Doped Strontium Molybdate with Exsolved Ni Nanoparticles as Anode Material for Solid Oxide Fuel Cells

Contact Info

Product

Resources

About

Investigation into the effect of Fe-site substitution on the performance of Sr2Fe1.5Mo0.5O6−δ anodes for SOFCs

Cited by 77 publications

References 35 publications

Enhanced Anode Performance and Coking Resistance by In Situ Exsolved Multiple-Twinned Co–Fe Nanoparticles for Solid Oxide Fuel Cells

Enhanced Anode Performance and Coking Resistance by In Situ Exsolved Multiple-Twinned Co–Fe Nanoparticles for Solid Oxide Fuel Cells

Positive Effects of H2O on the Hydrogen Oxidation Reaction on Sr2Fe1.5Mo0.5O6−δ-Based Perovskite Anodes for Solid Oxide Fuel Cells

Vanadium-Doped Strontium Molybdate with Exsolved Ni Nanoparticles as Anode Material for Solid Oxide Fuel Cells

Contact Info

Product

Resources

About

Investigation into the effect of Fe-site substitution on the performance of Sr₂Fe_1.5Mo_0.5O_6−δ anodes for SOFCs

Positive Effects of H₂O on the Hydrogen Oxidation Reaction on Sr₂Fe_1.5Mo_0.5O_6−δ-Based Perovskite Anodes for Solid Oxide Fuel Cells