Frontiers in Chemistry
·
2022
·
IF 5.545
Liang Qingwen,Tang Ping,Zhou Jing,Bai Jinghe,Tian Dan,Zhu Xiaofei,Zhou Defeng,Wang Ning,Yan Wenfu
Solid state electrolytes have been intensively studied in the solid oxide fuel cells (SOFCs). The aim of this work is to investigate the effects of MgO and Fe2O3 dual sintering aids on the microstructure and electrochemical properties of solid state Gd0.2Ce0.8O2-δ (GDC) electrolytes, which are prepared by a sol-gel method with MgO and Fe2O3 addition to the GDC system. It is found that the addition of MgO and Fe2O3 can reduce the sintering temperature, increase densification and decrease the grain boundary resistance of the electrolyte. The 2 mol% MgO and 2 mol% Fe2O3 co-doped GDC (GDC-MF) exhibits the highest grain boundary conductivity. At 400°C, the grain boundary conductivity and total conductivity of GDC-MF are 15.89 times and 5.56 times higher than those of GDC. The oxygen reduction reaction (ORR) rate at the electrolyte/cathode interface of GDC-MF is 47 % higher than that of GDC. Furthermore, the peak power density of a single cell supported by GDC-MF is 0.45 W cm−2 at 700°C, 36.7% higher than that of GDC. Therefore, the GDC-MF should be a promising electrolyte material for intermediate-temperature solid oxide fuel cells (IT-SOFCs).
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE
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2022
·Vol. 57
·期 30
·14398-14412
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IF 4.682
Zhou Dacheng,Yuan Chuan,Chen Xiyong,Chen Fangze,Xiong Xueqing,Liu Yihui,Yan Jialin,Fujita Toyohisa
Double-perovskite materials La 1− x Pr x BaCo 2 O 5+ δ (LPBCO), suitable for the application of intermediate-temperature solid oxide fuel cell (IT-SOFC) and other electrochemical devices, were successfully prepared through solid-state reaction method. The effects of La and Pr doping ratios on the crystallographic structure, thermochemical stability, thermal expansion, electrical conductivity, and electrochemical polarizations were analyzed and discussed. The X-ray diffraction results show that the crystal structure changes from single perovskite to double perovskite with the increase in Pr doping content. LPBCOs present excellent chemical stability with conventional electrolyte GDC at less than 1100 °C. The thermal expansion can be effectively reduced upon doping of Pr. The materials demonstrate high electrical conductivity even under relatively low temperatures, i.e., LP-73 ( x = 0.3 with single perovskite) has the highest conductivity at 1680 S/cm at 400 °C. Among the double-perovskite compositions, LP-55 presents the highest performance in electrical conductivity though. Analysis of the electrochemical impedance spectra of LPBCOs symmetric cells reveals low area specific polarization resistances for these double-lanthanide-doped double-perovskite materials, and the charge transfer is determined as the dominating sub-process for the oxygen transport through the materials. All the findings show that La 1− x Pr x BaCo 2 O 5+ δ possesses excellent oxygen reduction activity and is promising for the application in IT-SOFCs.
研究领域:
材料科学
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能源技术
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Qingjun Zhou,Yuhan Gong,Xinyue Zhang,Zilun Xia
A series of cathode materials of Pr 2-x Sr x NiO 4 (x = 0, 0.3, 0.5, 0.7, 1, 1.5) are synthesized by the EDTA-citric acid route. The results show that the Pr 1.7 Sr 0.3 NiO 4 , Pr 1.5 Sr 0.5 NiO 4 , Pr 1.3 Sr 0.7 NiO 4 and PrSrNiO 4 exhibit excellent structural stability and carbon dioxide resistance, and also exhibit good chemical compatibility and thermal matching with the SDC electrolyte. It is also found that the Sr doping is beneficial in improving the high temperature conductivity of Pr 2-x Sr x NiO 4 . At 800 °C, the electrical conductivity of Pr 1.5 Sr 0.5 NiO 4 and Pr 1.3 Sr 0.7 NiO 4 reaches 185 S cm −1 and 317 S cm −1 , respectively. In addition, the area-specific resistance (ASR) value increases significantly with Sr doping, which reduces the catalytic activity of the material. Acceptable ASR values are obtained for Pr 1.5 Sr 0.5 NiO 4 and Pr 1.3 Sr 0.7 NiO 4 , with ASR values of 0.079 Ω cm 2 and 0.082 Ω cm 2 at 800 °C, respectively. Additionally, the most interesting result is the ASR value obtained after high-temperature thermal decomposition of Pr 2 NiO 4 , where Pr 2 NiO 4 * (decomposed) has the lowest ASR value of only 0.027 Ω cm 2 at 800 °C, showing the best catalytic activity. The maximum power densities of Pr 2-x Sr x NiO 4 (x = 0.5 and 0.7) and Pr 2 NiO 4 * are found to be 515, 430, and 548 mW cm −2 at 800 °C, respectively. These results show that when the Sr doping amount is less than 1.5, the stability of the Pr 2-x Sr x NiO 4 cathode material can be effectively improved, but its catalytic performance is partially sacrificed.
研究领域:
材料科学
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能源科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2016
·
IF 3.205
Shengli Pang,Wenzhi Wang,Tao Chen,Yonggang Wang,Kaijie Xu,Xiangqian Shen,Xiaoming Xi,Jiwei Fan
An understanding of the relationships between the processing, compositions , and properties of perovskites is vitally important in the search for high performance cathode materials for intermediate-temperature solid oxide fuel cells (IT-SOFCs). In this work, the properties of PrBa 1−x Co 2 O 5+δ (x = 0.00–0.10) double perovskites were modified by introducing K during synthesis, and their performances as the cathode materials for IT-SOFCs were then characterized. The addition of K resulted in a greater cation deficiency in the double perovskites, improving bulk oxygen transport. However, K addition also markedly decreased the Co ion content on the perovskites' surfaces, which significantly deteriorated the perovskites’ electrochemical performances related to the surface exchange of oxygen.
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
ELECTROCHIMICA ACTA
·
2016
·
IF 4.803
Silin Li,Hengyong Tu,Lijun Yu,Muhammad Tuoqeer Anwar
Nd 2 NiO 4+δ (NNO)-Ce 0.8 Gd 0.2 O 2−δ (CGO) composites were investigated as cathodes for intermediate temperature solid oxide fuel cells (IT-SOFCs). Planar NiO-YSZ anode-supported cells in size of 50 mm × 50 mm were fabricated with YSZ as the electrolyte. The effects of sintering temperature and the relative proportions of NNO and CGO on the cell performance were investigated in combination with chemical reactivity tests of NNO-YSZ and NNO-CGO. NNO-CGO composite cathodes were successfully sintered on YSZ electrolyte at 1000 °C. By using La 0.6 Sr 0.4 CoO 3−δ (LSC) as current collector, the cell with 70NNO-30CGO composite cathode sintered at 1000 °C exhibited the highest power density of 620 mW cm −2 (at 0.7 V) and the lowest polarization resistance of 0.302 Ω cm 2 at 800 °C. Short-term durability studies revealed that the degradation of cell performance was attributed to the crack formation on the LSC current collector layer and the delamination between NNO-CGO cathode layer and LSC current collector layer.
研究领域:
材料科学
·
能源工程
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2021
·
IF 5.816
Zhiying Han,Jinghe Bai,Xu Chen,Xiaofei Zhu,Defeng Zhou
The cobalt-free cathode materials with high activity is critical to the commercial application of medium temperature solid oxide fuel cells (IT-SOFC). Herein, a series of cobalt-free Nb-doped Pr 2 Ni 1- x Nb x O 4 ( x = 0, 0.05, 0.10, and 0.15) perovskite oxides were successfully prepared, and the effects of Nb-doping on the structure, thermal stability and electrochemical properties of the cathode material are studied in detail. The Pr 2 Ni 1- x Nb x O 4 exhibits a K 2 NiF 4 type structure with Fmmm space group. The Nb 5+ cations that doped into Pr 2 NiO 4 replaces the Ni site, which increases the surface oxygen content, then effectively eliminates the phase transition of Pr 2 NiO 4 and significantly improves the ORR catalytic activity . The Pr 2 Ni 0.9 Nb 0.1 O 4 was found to occupy the lowest polarization resistance of 0.057 Ω cm 2 , and the peak power density of single cells supported by the electrolyte is 0.576 W cm −2 at 700 °C, which has good long-term stability.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
Nano Research
·
2021
·Vol. 15
·期 4
·3264-3272
·
IF 8.897
Cai Changkun,Xie Manyi,Xue Ke,Shi Yu,Li Shuting,Liu Yuanyuan,An Shengli,Yang Hong
La 06 Sr 04 Co 02 Fe 08 O 3− δ (LSCF) is recognized as one of the most promising cathode materials for the highly-desired intermediate-temperature solid oxide fuel cell (IT-SOFC) technology. However, it is still challenged by polarization losses due to reduced operation temperatures. In this work, a series of Ba 2+ -doped La 0.6− x Ba x Sr 0.4 Co 0.2 Fe 0.8 O 3− δ (LBSCF x, x = 0.05, 0.10, 0.15, and 0.20) materials are successfully synthesized and their electrochemical performances are evaluated as a cathode for IT-SOFC technology. The study shows that, compared to the un-doped LSCF, the Ba 2+ -doped LBSCF possess higher electrical conductivities at 500–800 °C and display lower polarization resistances to oxygen adsorption/dissociation. As a result, the Ni-SDC|SDC|LBSCF0.20 cell (SDC = samarium-doped cerium, Sm 0.2 Ce 0.8 O 1.9 ) delivers a high maximum power density of 0.704 W/cm 2 at 750 °C, which is > 30% higher than the Ni-SDC|SDC|LSCF cell. This work reveals that Ba 2+ -doping is effective in enhancing oxygen catalytic activity of LSCF-based cathode materials, demonstrating a new and commercial-feasible strategy in developing high performance cathode materials for the IT-SOFC technology.
研究领域:
材料科学
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2018
·
IF 5.116
Yu-Jun Jin,Zhan-Guo Liu,Zhao-Ying Ding,Gui Cao,Abdelkhalek Henniche,Hai-Bin Zhang,Xu-Yang Zhen,Jia-Hu Ouyang
A novel GdSmZr 2 O 7 –(Li 0.52 Na 0.48 ) 2 CO 3 composite electrolyte material is successfully developed by pressureless-sintering for intermediate temperature solid oxide fuel cells. GdSmZr 2 O 7 nanopowders are synthesized by a low cost chemical coprecipitation and calcination method. The phase structure and morphology as a function of the calcination temperature are investigated by means of X-ray diffraction, scanning electron microscopy and transmission electron microscopy . The resulting GdSmZr 2 O 7 nanopowders after calcination at 800 °C for 5 h exhibit good crystallization and uniform particle morphology with an average size of 50 nm. The GdSmZr 2 O 7 –40 wt.% (Li 0.52 Na 0.48 ) 2 CO 3 composite sintered at 600 °C for 1 h has a high conductivity of 0.54 S cm −1 at a temperature of 600 °C. From the Arrhenius curve of the composite, the activation energy has different temperature behaviors around the knee region of 480 °C, where the slope changes and separates the intrinsic oxygen vacancy conduction dominated region from the ‘superionic highway’ region. For GdSmZr 2 O 7 –40 wt.% (Li 0.52 Na 0.48 ) 2 CO 3 composite at temperatures above 480 °C, there is good correlation between ionic diffusivity and conductivity. The introduction of (Li 0.52 Na 0.48 ) 2 CO 3 carbonate into GdSmZr 2 O 7 ceramics significantly promotes the enhancement of its conductivity by one or two orders of magnitude at the intermediate temperatures, especially above 480 °C. A maximum power density of 221 mW cm −2 at 650 °C was achieved for excellent performance of fuel cell based on GSZ–40LN composite electrolyte.
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
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2019
·
IF 7.467
Jianqiu Wang,Xu Chen,Shenkun Xie,Lei Chen,Yuan Wang,Jian Meng,Defeng Zhou
We demonstrate the utilization of bismuth tungstate (Bi 2 WO 6 , BW) as a sintering aid and reinforcement component into neodymium-doped ceria (Nd 0.2 Ce 0.8 O 3-δ , NDC) to fabricate bismuth tungstate/neodymium-doped ceria composite electrolyte for intermediate-temperature solid oxide fuel cells (IT-SOFC). The presence of BW lowers the sintering temperature of NDC electrolyte to 1000 °C. Moreover, at 600 °C, the electrical conductivity of 5 mol.% BW-incorporated NDC (5BW-NDC) composite electrolyte is 7.12 times higher than the NDC. It is worth mentioning that the enhanced electrical conductivity of 5BW-NDC composite electrolyte does not include the contribution from electronic conductivity . Furthermore, NDC and 5BW-NDC exhibit excellent compatibility with La 0.6 Sr 0.4 Co 0.8 Fe 0.2 O 3-δ cathode and NiO anode in terms of thermal expansion coefficient and chemical reactivity . The oxygen reduction reaction at 5BW-NDC composite electrolyte/cathode interface is significantly enhanced by ∼40% compared to NDC. Moreover, 5BW-NDC electrolyte-supported SOFC delivers a power density of 0.86 W cm −2 at 700 °C, which is 45.76% higher than the NDC-based SOFC. The output performance remains stable during high-temperature operation for 120 h, which indicates the stability and chemical compatibility of the as-synthesized composite electrolyte with other cell components. The results reveal that BW-NDC composite is a potential electrolyte material for stable and high-performance IT-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
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2019
·
IF 4.084
Xiyu Nie,Dan Zheng,Ying Chen,Baoyuan Wang,Chen Xia,Wenjing Dong,Xunying Wang,Hao Wang,Bin Zhu
High power density performance at intermediate (600 °C–450 °C) temperatures (IT) must be considered in the development of solid oxide fuel cell (SOFC). A niobium and tantalum co-doped perovskite material SCNT (SrCo 0. 8 Nb 0 . 1 Ta 0 . 1 O 3-δ ) can be used as a cathode for IT-SOFC due to its (H + /O 2− /e − ) triple conduction and promising catalysis activity. In this work, the SCNT was composited with ionic conductor SCDC(Ce 0.8 Sm 0.05 Ca 0 . 15 O 2-δ ) and processed as electrolyte membrane into semiconductor-ionic membrane fuel cell (SIMFC), which delivered an appreciable performance at IT, i.e., a peak power output of 1016 mW/cm 2 at 550 °C and 401 mW/cm 2 at 450 °C, respectively. The high performance mainly originated from the (H + /O 2− ) dual-ion conduction of SCNT as well as the high oxygen ion conductivity of SCDC, the SCNT-SCDC electrolyte layer adjacent to cathode have promoted the oxygen reduction reaction (ORR) with some extent because of the excellent catalysis activity of SCNT. Moreover, the on-line generated carbonate suppressed the electronic conductivity and resulted in the attractive density of SCNT-SCDC electrolyte to further contribute to the desired cell performance.
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
ELECTROCHIMICA ACTA
·
2013
·
IF 3.777
Fucun Wang,Dengjie Chen,Zongping Shao
Ba 1− x Co 0.7 Fe 0.2 Nb 0.1 O 3− δ oxides ( x = 0, 0.05 and 0.10) were optimized as potential cathodes on oxygen ionic conductor electrolyte for intermediate temperature solid oxide fuel cells (IT-SOFCs). The creation of additional oxygen vacancies in Ba 0.9 Co 0.7 Fe 0.2 Nb 0.1 O 3− δ was confirmed. Low polarization resistances of 0.015, 0.029 and 0.089 Ω cm 2 were achieved at 700, 650 and 600 °C, respectively. By further optimizing the microstructure of the Ba 0.9 Co 0.7 Fe 0.2 Nb 0.1 O 3− δ electrode by using polyvinyl butyral as a pore former and adjusting the sintering temperature, the maximum power density was improved from 682 to 955 mW cm −2 at 650 °C. The operational stability of the Ba 0.9 Co 0.7 Fe 0.2 Nb 0.1 O 3− δ electrode was also investigated. The CO 2 in the surrounding air was detrimental to the oxygen reduction reaction ; however, the performance of the cell was recovered after removing the CO 2 in the air at 650 or 700 °C. In addition, the Ba 0.9 Co 0.7 Fe 0.2 Nb 0.1 O 3− δ electrode in symmetrical cells exhibited a stable performance at 650 °C for 400 h and maintained a reliable performance after repeated thermal cycles from room temperature to 700 °C. The results showed that Ba 0.9 Co 0.7 Fe 0.2 Nb 0.1 O 3− δ was a promising cathode material for practical application in IT-SOFCs.
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
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Ru-Yi Chen,De-Feng Zhou,Xiao-Fei Zhu,Ning Wang,Jing-He Bai,Chun-Qi Guo,Lian Ai
Cobalt-based perovskites are widely used as cathode materials for intermediate temperature solid oxide fuel cells (IT-SOFCs) due to their excellent catalytic activities. In this paper, a series of Nb-doped La 0.5 Sr 0.5 Co 0.8 Cu 0.2- x Nb x O 3–δ (LSCCu 0.2- x Nb x O 3-δ , x = 0.00 ≤ x ≤ 0.075) cathode materials with excellent electrochemical performance are prepared by a Pechini method, and the critical Nb-doping effect is studied in detail. In the new cathode material, the surface oxygen content increases with the Nb doping, while the segregation of Sr and the coefficient of thermal expansion (TEC) is reduced. The optimum LSCCu 0.15 Nb 0.05 O 3-δ shows the highest surface oxygen content, the lowest surface Sr content, and the highest oxygen reduced reaction (ORR) catalytic activity. At 700 °C, the polarization resistance (Rp) is 0.065 Ω cm 2 , and the peak power density (PPD) of single cells supported by the electrolyte is 518 mW cm −2 , which are promising for the IT-SOFCs. Therefore, the LSCCu 0.15 Nb 0.05 O 3-δ should be a promising cathode material for the high-performance IT-SOFCs.
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
危险品化学品经营许可证（带存储）