ADVANCED FUNCTIONAL MATERIALS
·
2024
·
IF 18.5
Yang Gao,Min Fu,Shuang Zhao,Zhongyu Hou,Kechen Liu,Xiangbo Deng,Zetian Tao
One of the key challenges for high-performance proton-conducting solid oxide fuel cells (H-SOFCs) is the mismatch in thermal expansion coefficients (TEC) between the cathode and electrolyte. While incorporating negative thermal expansion (NTE) materials can mitigate this issue, mechanical mixing often weakens cathode strength. To address this, a TEC gradient cathode is proposed and successfully implemented by co-sintering PrBa(Co 0.7 Fe 0.3 ) 2 O 5-δ (PBCF) with Y 2 W 3 O 12 (YWO) in this work. In this work, Ba atoms at the A-site of PBCF migrated from the lattice, generating A-site defects. The resulting BaWO 4 and Y 10 W 8 O 21 phases, which have low TEC, are uniformly distributed between PBCF and YWO, forming a TEC gradient composite cathode. In addition, the transition phase captures the A-site element Ba in the electrolyte layer, optimizing the electrolyte-cathode interface. The composite cathode exhibits a reduced TEC, closely matching that of the electrolyte, significantly enhancing interface bonding, thereby providing a lower ohmic resistance of 0.051 Ω cm 2 and a higher power density of 1.88 W cm −2 at 700 °C. Remarkably, thermal cycling tests conducted under temperature switching conditions demonstrate the composite cathode's long-term thermal and chemical stability.
研究领域:
材料科学
·
能源工程
✓ 已验证
DOI
高影响因子
Journal of Advanced Ceramics
·
2022
·Vol. 11
·期 5
·794-804
·
IF 11.534
Xu Yangsen,Xu Xi,Bi Lei
A high-entropy ceramic oxide is used as the cathode for the first time for proton-conducting solid oxide fuel cells (H-SOFCs). The Fe 0.6 Mn 0.6 Co 0. 6 Ni 0.6 Cr 0.6 O 4 (FMCNC) high-entropy spinel oxide has been successfully prepared, and the in situ chemical stability test demonstrates that the FMCNC material has good stability against CO 2 . The first-principles calculation indicates that the high-entropy structure enhances the properties of the FMCNC material that surpasses their individual components, leading to lower O 2 adsorption energy for FMCNC than that for the individual components. The H-SOFC using the FMCNC cathode reaches an encouraging peak power density (PPD) of 1052 mW·cm −2 at 700 °C, which is higher than those of the H-SOFCs reported recently. Additional comparison was made between the high-entropy FMCNC cathode and the traditional Mn 1. 6 Cu 1.4 O 4 (MCO) spinel cathode without the high-entropy structure, revealing that the formation of the high-entropy material allows the enhanced protonation ability as well as the movement of the O p-band center closer to the Fermi level, thus improving the cathode catalytic activity. As a result, the high-entropy FMCNC has a much-decreased polarization resistance of 0.057 Ω·cm 2 at 700 °C, which is half of that for the traditional MCO spinel cathode without the high-entropy design. The excellent performance of the FMCNC cell indicates that the high-entropy design makes a new life for the spinel oxide as the cathode for H-SOFCs, offering a novel and promising route for the development of high-performance materials for H-SOFCs.
研究领域:
材料科学
·
能源工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2021
·
IF 9.127
Xin Zhou,Nianjun Hou,Tian Gan,Lijun Fan,Yongxin Zhang,Jingyu Li,Ge Gao,Yicheng Zhao,Yongdan Li
BaCe 0.2 Fe 0.8-x Pr x O 3-δ (x = 0–0.3) is studied as a cobalt-free cathode material for proton-conducting solid oxide fuel cells. The cathode is composed of a cubic BaFeO 3-δ phase and an orthorhombic BaCeO 3-δ phase, and Pr is doped in both phases. The partial substitution of Pr for Fe decreases the content of the BaFeO 3-δ phase, leading to a lower electrical conductivity . BaCe 0.2 Fe 0.6 Pr 0.2 O 3-δ has the most adsorbed oxygen and Fe 3+ on the surface, resulting in the fastest oxygen surface exchange kinetics and the highest activity. The partial pressure of H 2 O shows a negligible effect on the polarization resistance of the cathode. In contrast, the polarization resistance increases remarkably with the decrease of oxygen partial pressure , indicating that the rate of the cathode process is controlled by the surface exchange of oxygen. At 700 °C, BaCe 0.2 Fe 0.6 Pr 0.2 O 3-δ shows the lowest polarization resistance of 0.057 Ω cm 2 , and a single cell with that cathode exhibits the highest maximum power density of 562 mW cm −2 . The results demonstrate that Pr doped BaCe 0.2 Fe 0.8 O 3-δ is a promising cobalt-free cathode material for proton-conducting solid oxide fuel cells.
研究领域:
材料科学
·
能源科学
✓ 已验证
DOI
高影响因子
APPLIED ENERGY
·
2019
·
IF 8.426
Yidan Zhang,Ankang Zhu,Youmin Guo,Chunchang Wang,Meng Ni,Hao Yu,Chuanhui Zhang,Zongping Shao
Proton conducting solid oxide fuel cells are solid state electrochemical devices for power generation at a conversion efficiency (>60%) higher than conventional thermal power plants (∼40%). The cathode is the key component of proton conducting solid oxide fuel cells as it contributes to more than 50% of the total overpotential loss of an H + -SOFC with thin film electrolyte. This work aims to develop high performance and durable cathode for proton conducting solid oxide fuel cells by doping Ba 2+ into the Sr-site of the SrSc 0.175 Nb 0.025 Co 0.8 O 3-δ perovskite oxide. The influence of moisture on the catalytic activity of Ba 0.5 Sr 0.5 Sc 0.175 Nb 0.025 Co 0.8 O 3-δ cathode was investigated using electrochemical impedance spectroscopy of symmetric cell at 600 °C. The resistance in the low-frequency range was found to be the rate-limiting step of the oxygen reduction reaction in the dry air, while the resistance in the medium-frequency range became the rate-limiting step in the moist air. With a Ba 0.5 Sr 0.5 Sc 0.175 Nb 0.025 Co 0.8 O 3-δ cathode, a proton conducting single cell achieved good performance at a temperature of 700 °C with a power density of 633 mW cm −2 . However, the performance of single cell decreased with time, probably due to the agglomeration of cathode particles and the coverage of produced water on the active surface. To improve the durability of the proton conducting solid oxide fuel cell, it is critical to minimize the cathode particle agglomeration and remove the produced water effectively. The research results contribute to the development of high-performance fuel cell for efficient energy conversion.
研究领域:
材料科学
·
能源工程
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Hao Qiu,Mingzhuang Liang,Jing Zhao,Zhixian Liang,Shanshan Jiang,Huangang Shi,Wei Wang,Huabing Wen,Chao Su
In order to accelerate the widespread application of solid oxide fuel cells (SOFCs), especially proton-conducing solid oxide fuel cells (PCFCs), it is crucial to develop a cathode material with high activity for the oxygen reduction reaction (ORR), excellent long-term stability and CO 2 tolerance. Herein, an A-site deficient cobalt-free (Co-free) perovskite oxide Sr 0.95 Ta 0.1 Fe 0.9 O 3-δ (S 0.95 TF) is prepared by introducing cation deficiencies into SrTa 0.1 Fe 0.9 O 3-δ (STF), and it proves to be a highly active cathode. The increased oxygen vacancies , the decreased thermal expansion coefficient (TEC) value and improved CO 2 tolerance, efficiently enhance electrochemical performance and durability during long-term stability testing. As a result, the area specific resistance (ASR) values of S 0.95 TF at 600 °C are only 0.095 and 0.42 Ω cm 2 with the Sm 0.2 Ce 0.8 O 1.9 (SDC) and BaZr 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3-δ (BZCYYb) electrolytes, respectively. In addition, both of the single cells with S 0.95 TF cathodes, based on different electrolytes, can function stably for 200 h without obvious performance decrease. These results clearly demonstrate that S 0.95 TF is a highly promising candidate for both oxygen ion-conducting SOFCs and PCFCs.
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Jie Zheng,Ying Li,Yongtao Huang,Zezhong Wang,Wei Zhang,Chunsheng Zhuang
The cathode is a critical component of proton-conducting fuel cells (H-SOFCs), as its performance is influenced by the distinct atmospheric conditions on the cathode side. In this study, Pr 6 O 11 was incorporated into the BaCo 0.5 Fe 0.5 O 3-δ cathode material to form BaCo 0.5 Fe 0.5 O 3-δ -Pr 6 O 11 heterostructured composites. These heterostructures significantly enhance oxygen ion diffusion and valence electron transitions, leading to improved electrical conductivity and electrocatalytic activity in H-SOFCs. XPS analysis demonstrated that the BaCo 0.5 Fe 0.5 O 3-δ -Pr 6 O 11 cathode exhibits superior chemical stability and oxygen adsorption capacity. Symmetric cell tests revealed that its polarization impedance is significantly lower than that of single-phase BaCo 0.5 Fe 0.5 O 3-δ , indicating excellent ORR activity. Furthermore, an H-SOFC with a BaCo 0.5 Fe 0.5 O 3-δ -Pr 6 O 11 cathode achieved a peak power density of 847 mW cm −2 at 700 °C, markedly outperforming the single-phase cathode.
研究领域:
材料科学
·
能源工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2020
·
IF 8.247
Jun Li,Jie Hou,Ying Lu,Qi Wang,Xiuan Xi,Yun Fan,Xian-Zhu Fu,Jing-Li Luo
CO 2 -poisoning effect on cathodes is an unnegligible problem for commercial application of solid oxide fuel cells (SOFCs). In order to enhance CO 2 tolerance of cathodes, partial replacement of Ba by Ca in BaCo 0·4 Fe 0·4 Zr 0·1 Y 0·1 O 3-δ (BCFZY) cathode is proposed in this study. The stability of Ba 0·95 Ca 0·05 Co 0·4 Fe 0·4 Zr 0·1 Y 0·1 O 3-δ (BCaCFZY) and BCFZY in CO 2 -containing atmosphere is investigated comparably. When tested in a symmetrical cell and exposed to air with 1% CO 2 or 10% CO 2 , the electrochemical performance of BCFZY cathode shows obviously degradation and carbonate particles are formed on the cathode surface . Exhilaratingly, the polarization resistance of BCaCFZY cathode is more stable and the cathode surface remains clean. The durability test in proton-conducting single cells further proves that the fine stability of BCaCFZY cathode can be achieved in air with 1% CO 2 atmosphere. In addition, thermodynamic analysis reveals the mechanism of Ca doping to improve stability. Ca dopant itself has a high CO 2 resistance and the introduction of Ca element reduces Ba segregation on surface. Base on the experimental results above, the BCaCFZY cathode is a promising candidate for SOFC applications .
研究领域:
材料科学
·
能源工程
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2023
·
IF 6.7
Junyi Gong,Jie Hou
Meliorating the particle surface could alter the surface properties, thus potentially enhancing the electrode reactions. In this assignment, a recovery of the intrinsic nanostructure at La 1.2 Sr 0.8 Ni 0.5 Mn 0.5 O 4+δ (LSNM) particle surface with the elimination of the bi-shell nano-surface layers caused by dopant segregation was attempted based on the lower powder calcination temperature and introduction of A-site cation deficiency. The A-site deficient (La 1.2 Sr 0.8 ) 0.9 Ni 0.5 Mn 0.5 O 4+δ [D-LSNM], accompanied with no phase separation on surface, is successfully obtained, in which the smaller particles and more oxygen vacancies would promote the electrocatalysis, oxygen reduction reaction and oxygen migration, thus boosting the electrode reactions. The surface nanostructure-recovered D-LSNM cathode achieves a preeminent performance with power output of 1547 and 1030 mW cm −2 at 700 and 600 °C, being better than other K 2 NiF 4 -type R-P cathodes in the literature. Anyhow, the preferable cell performance along with the fine stability suggests that the original surface-nanostructured D-LSNM is a promising cathode alternative for low-temperature proton-conducting solid oxide fuel cells. This work provides a new kind of reverse thinking to design highly catalytically active cathode materials via the restoration of the intrinsic nanostructure at surface, which would be beneficial to the related electrocatalytic fields.
研究领域:
材料科学
·
电化学
·
能源材料
·
燃料电池
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Shenglin Liu,Wu Menglin,Lanying Lu,Jiupai Ni,Chengsheng Ni,John T.S. Irvine
La 0.5 Ba 0.5 Cu x Fe 1−x O 3−δ (0 ≤ x ≤ 1) perovskite was investigated as a cathode for a protonic solid oxide fuel cell (H-SOFC) using BaZr 0.1 Ce 0.7 Y 0.2 O δ (BZCY) electrolyte. A maximum electric conductivity (76.84 S cm −1 at 700 °C) was achieved in the air at the composition of La 0.5 Ba 0.5 Cu 0.4 Fe 0.6 O 3−δ . Comparing to La 0.5 Ba 0.5 CuO 3−δ (LBC), the increase in Fe content increased the D chem (1.07x10 −5 to 1.74x10 −5 cm 2 S −1 ) and K chem (1.12x10 −10 to 3.01x10 −10 cm 2 S −1 ) at La 0.5 Ba 0.5 Cu 0.2 Fe 0.8 O 3−δ (LBCF28) but decreased the proton conductivity from 7.5 to 4.3 mS cm −1 . Either Fe doping in LBC or Cu doping in La 0.5 Ba 0.5 FeO 3−δ increased the thermal expansion coefficient (TEC), but a low TEC among samples with mixed cations was achieved at La 0.5 Ba 0.5 Cu 0.5 Fe 0.5 O 3−δ (LBCF55) (16.12 ppm K −1 ). LBC suffered from superficial decomposition in the ambient air, causing an ohmic resistance loss of the full cell on Ni(O)-BZCY support. A high initial cell performance (820 mW cm −2 ) can be achieved for the cell with LBCF55 and LBCF28 cathode but the latter was unstable under a cathodic bias owing to the increase in ohmic resistance owing to the production of intermediate layer between electrode and electrolyte. With better stability than LBCF28 and higher performance than LBC, LBCF55 was regarded as a viable cathode material for H-SOFC. This work explores systematically the behavior of a perovskite with mixed Cu and Fe cations as a cathode for H-SOFCs.
研究领域:
材料科学
·
能源
·
电化学
·
燃料电池
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）