SEPARATION AND PURIFICATION TECHNOLOGY
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2022
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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
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能源
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电化学
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燃料电池
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2024
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IF 8.4
Xianfeng Guan,Wanzhen Wu,Shuyu Zhang,Guangpeng Ma,Xinpu Zhou,Cuicui Li,Di Yu,Yu Luo,Shuang Wang
ABSTRACT Achieving the right balance between electrical conductivity and long-term reliability in high-temperature proton exchange membrane (HT-PEM) technologies contributes to sustainable energy recycling. This study involves a groundbreaking effort to create amphiphilic polybenzimidazoles by incorporating 2-isocyanatopyridine into hydroxy-polybenzimidazole (OHPBI). A high hydrogen-bond density network is constructed through two-by-two interactions between the hydroxyl group, the imidazole molecule and quaternary ammonium group. Quaternary ammonium polymeric ionic liquid is introduced to maintain high phosphoric acid (PA) doping and PA retention. The PA retention of the amphiphilic polybenzimidazole membrane is 87.5% after 240 h at 160 °C/0% RH. Furthermore, the peak power density of the amphiphilic polybenzimidazole membrane reach 837.8 mW cm -2 at 180 °C and the voltage decay rate is 0.23 mV h -1 after long-term operation. More specifically, the amphiphilic polybenzimidazole membranes show a conductivity of 138.9 mS cm -1 at 180 °C. This indicates that the amphiphilic polybenzimidazole membrane has both high power output and long-term stability. This work introduces an innovative method to improve the efficiency of PBI-based HT-PEM.
研究领域:
材料科学
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化学工程
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能源技术
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聚合物化学
✓ 已验证
产品关联
DOI
高影响因子
Nature Communications
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2018
·Vol. 9
·期 1
·1-7
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IF 12.353
Ge Xiaolin,He Yubin,Liang Xian,Wu Liang,Zhu Yuan,Yang Zhengjin,Hu Min,Xu Tongwen
Synthetic polyelectrolytes, capable of fast transporting protons, represent a challenging target for membrane engineering in so many fields, for example, fuel cells, redox flow batteries, etc. Inspired by the fast advance in molecular machines, here we report a rotaxane based polymer entity assembled via host–guest interaction and prove that by exploiting the thermally triggered translational motion (although not in a controlled manner) of mechanically bonded rotaxane, exceptionally fast proton transfer can be fulfilled at an external thermal input. The relative motion of the sulfonated axle to the ring in rotaxane happens at ~60 °C in our cases and because of that a proton conductivity (indicating proton transfer rate) of 260.2 mS cm −1 , which is much higher than that in the state-of-the-art Nafion, is obtained at a relatively low ion-exchange capacity (representing the amount of proton transfer groups) of 0.73 mmol g −1 .
研究领域:
材料科学
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化学工程
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电化学
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分子机器
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2024
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IF 9.4
Ning Liu,Shuguang Bi,Ying Ou,Hai Liu,Yi Zhang,Chunli Gong
Proton exchange membranes with high ionic conductivity and good chemical stability are critical for achieving high power density and long lifespan of direct methanol cells (DMFCs). Herein, a zwitterionic molecule was grafted onto the surface of polyvinylidene fluoride (PVDF) nanofibers to obtain functionalized PVDF porous substrate (SBMA-PDA@PVDF). Then, sulfonated poly(ether ether ketone) (SPEEK) was filled into the pores of SBMA-PDA@PVDF, and further ionic cross-linked via H 2 SO 4 to prepare the composite membrane (SBMA-PDA@PVDF/SPEEK). The basic groups on the zwitterionic interface could not only establish ionic cross-linking with SPEEK to increase chemical stability and reduce swelling, but also serve as the adsorption sites for subsequent H 2 SO 4 cross-linking to significantly enhance proton conductivity. Super-high proton conductivity (165.34 mS cm −1 , 80 °C) was achieved for the membrane, which was 2.12 times higher than that of the pure SPEEK. Moreover, the SBMA-PDA@PVDF/SPEEK membrane exhibited remarkably improved oxidative stability of 91.6 % mass retention after soaking in Fenton’s agent for 12 h, while pure SPEEK completely decomposed. Satisfactorily, the DMFC assembled with SBMA-PDA@PVDF/SPEEK exhibited a peak power density of 99.01 mW cm −2 , which was twice as much as that of commercial Nafion 212 (48.88 mW cm −2 ). After 235 h durability test, only 11 % voltage loss was observed.
研究领域:
材料科学
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电化学
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能源材料
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燃料电池技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2021
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IF 5.816
Xue Li,Shubo Wang,Hong Zhang,Cheng Lin,Xiaofeng Xie,Chenxing Hu,Ran Tian
Copoly (arylene ether sulfone)s was employed for proton exchange membrane preparation via atom transfer radical polymerization followed by mild sulfonation , enhanced phase-separated morphology and favorable proton conductivity were achieved. The comprehensive ex-situ properties of a range of membranes with different ion exchange capacities were characterized alongside the fuel cell performances investigation. The membranes exhibit higher water uptake, which is beneficial to the proton conduction, compared to Nafion® 211 while maintaining similar swelling ratio. The prepared membranes exhibit reasonably high proton conductivity (0.16 S/cm at 85 °C) benefitting from the well-defined microstructure and high connectivity of the hydrophilic domains. Considering the comprehensive property, membrane with moderate ion exchange capacity (1.39 mmol/g) was employed to fabricate the membrane electrode assembly and peak power density of 0.65 W/cm 2 at 80 °C, 60% relative humidity was achieved for a H 2 /O 2 fuel cell, these hydrocarbon membranes can therefore be implemented in PEMFCs.
研究领域:
材料科学
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化学工程
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电化学
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能源材料
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2023
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IF 9.5
Cong Wang,Yujiao Sun,Zhaoji Yang,Jiantao Fan,Hui Li,Shaoyi Xu
A carbon-carbon linked polyaromatic electrolyte was designed and synthesized for proton exchange membranes. The facile synthesis consists of a metal-free Friedel-Crafts polymerization and a direct post-sulfonation. To prevent the random sulfonation, the trifluorobuanone monomer was incorporated as a spacer to sterically confine the sulfonated area. Hydrophobic/hydrophilic separation was observed in the polymer's microstructure. The membrane (ion exchange capacity = 1.88 mmolg −1 ) displayed low water swelling (area swelling = 38.0% at 80 °C) at a slightly higher proton conductivity than Nafion 212. Tensile strength of 39.3 MPa and elongation at break of 67.0% were confirmed by stress-strain measurements. The membrane electrode assembly afforded an electrolyzing performance of 4.6 A cm −2 @2.0 V while Nafion 212 was 3.6 A cm −2 @2.0 V under the same testing conditions. The 45 μm film exhibited better stability than Nafion 212 (∼50 μm) both in the preliminary in-situ cyclic accelerated stress test and the 800-h galvanostatic evaluation. The degradation rate of our thin membrane in the 800-h test was comparable to that of Nafion 115 (∼125 μm).
研究领域:
材料科学
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电化学
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高分子化学
✓ 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）