JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2016
·Vol. 163
·期 13
·F1309
·
IF 3.014
Xiaojing Chen,Wen Wen,Jing Hu,Hejia Su,Haibin Li,Xiangyang Kong,Marta Boaventura
Based on CsH5(PO4)2, sulfonated poly(ether ether ketone) (SPEEK), and phosphosilicate sol, proton-conducting CsH5(PO4)2/phosphosilicate/SPEEK composite electrolyte membranes have been prepared by a sol–gel method followed by mechanical ballmilling. The chemical structures, morphologies, thermal performances, stability, and proton conductivities of the composite electrolyte membranes were investigated. After incorporating the SPEEK polymer, these composite membranes exhibited adequate flexibility and mechanical performance; despite inorganic content of up to 80 wt%, a tensile strength of 6.2 MPa was maintained. Specifically, the composite electrolyte membrane displays a high proton conductivity of 14.6 mS cm−1 at 250°C under 47% H2O/N2 atmosphere. A fuel cell equipped with the composite electrolyte membrane showed a stable output voltage over the continuous measurement of 50 h under a constant output current density of 40 mA cm−2.
研究领域:
材料科学
·
能源工程
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2022
·Vol. 169
·期 2
·024505
·
IF 4.386
Yifan Li,Jing Hu,Haibin Li,Li Chen
CsH5(PO4)2-doped polybenzimidazole (PBI) membranes exhibit good proton conductivity and mechanical properties. However, their application in fuel cells is impeded by poor performance. In this study, a novel method is confirmed to greatly improve the performance of a fuel cell based on a CsH5(PO4)2-doped PBI membrane. By coating phosphoric acid (PA) on the surface of the catalytic layer of the gas diffusion electrode, the interfacial contact between the electrolyte membrane and catalytic layer is improved, thereby reducing the ohmic resistance and improving the fuel cell performance. The cell performance is improved by ∼700%. Moreover, the effects of humidity and temperature on the performance and resistance analysis of membrane electrode assembly with a CsH5(PO4)2—doped PBI membrane are studied. Testing under a temperature range of 160 °C–220 °C and humidity range from dry to 30% relative humidity, a maximum peak power density of 554 mW cm−2 is found at 200 °C and 20% relative humidity. A durability test of the membrane electrode assembly indicates that its performance remains stable in a humid atmosphere but gradually decreases in a dry atmosphere. This means for the long-term operation of the molten proton conductor electrolyte membrane, a humid atmosphere is necessary to inhibit the performance decay.
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 MEMBRANE SCIENCE
·
2023
·
IF 9.5
Yutong Zhao,Bo Lv,Wei Song,Jinkai Hao,Junfang Zhang,Zhigang Shao
Conventional high-temperature proton exchange membranes use phosphoric acid (PA) as a proton conductor . However, PA loss, poor mechanical stability, and catalyst poisoning represent major limitations. Solid acids are an alternative to PA that does not require humidification and is less prone to leaching. In this study, we prepared two composite membranes by high-temperature impregnation to investigate the effects of the structure of polybenzimidazole (PBI) on the anchoring of solid acids: a laboratory-synthesized m -PBI/CsH 5 (PO 4 ) 2 and the commercial OPBI/CsH 5 (PO 4 ) 2 . Compared to PA-doped membranes, CsH 5 (PO 4 ) 2 -doped membranes showed excellent mechanical properties , particularly m -PBI/CsH 5 (PO 4 ) 2 . Scanning electron microscopy and energy dispersive spectroscopy images showed that CsH 5 (PO 4 ) 2 was uniformly dispersed on the surface and cross-section of both membranes, conducive to the formation of proton transport channels following the CsH 5 (PO 4 ) 2 melting in both samples. The characterization of the physical structures proved the interaction between the imidazole ring and solid acid. Furthermore, the proton conductivity without humidification was similar in m -PBI/CsH 5 (PO 4 ) 2 and OPBI/CsH 5 (PO 4 ) 2 , demonstrating the suitability of m -PBI for fuel cells production. To test this, we assembled a m -PBI/CsH 5 (PO 4 ) 2 cell that showed competitive performances, with a peak power density of 361.28 mW cm −2 at 160 °C in H 2 /O 2 atmosphere.
研究领域:
材料科学
·
燃料电池工程
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
·
2022
·Vol. 46
·期 15
·24148-24157
·
IF 4.672
Zhiyong Fu,Yifan Li,Joan Papavasiliou,Yijing Xing,Lei Liu,Zhuoqun Li,Li Chen,Haibin Li
Summary In this study, two kinds of membrane electrode assembly (MEAs) based on the CsH 5 (PO 4 ) 2 -doped polybenzimidazole (PBI) membrane and fabricated by the catalyst-coated membrane (CCM) method are reported. In the first one, named Type-GDL/PA MEA, phosphoric acid (PA) is sprayed onto the surface of the gas diffusion layer (GDL), and in the second one, named Type-CL/PA MEA, PA is sprayed onto the surface of the catalyst layer (CL). The results show that the Type-CL/PA MEA exhibits significantly higher performance than the Type-GDL/PA MEA, providing the highest peak power densities of 620 and 413 mW cm −2 at 180°C under humidified H 2 /O 2 and H 2 /air fuel cell conditions, respectively. Moreover, their performance is promoted in the presence of humidified gas feed streams as compared to dry gas conditions at the same temperature. The electrochemical impedance spectroscopy (EIS) analysis indicates a lower charge transfer resistance for the Type-CL/PA MEA as compared to the Type-GDL/PA MEA. The former MEA also presents higher stability, as confirmed by a 100 h durability test, resulting in a voltage degradation rate of 0.17 mV h −1 , which is much lower than the corresponding voltage drop of 0.71 mV h −1 for the Type-GDL/PA MEA. Novelty statement CCM-type MEAs for HT-PEMFC are studied. CCM-type MEAs with a CsH 5 (PO 4 ) 2 -doped Polybenzimidazole membrane are prepared. Type-GDL/PA MEA is to spray phosphoric acid onto the gas diffusion layer (GDL). Type-CL/PA MEA is to spray phosphoric acid onto the catalyst layer (CL). Type-CL/PA MEA exhibits significantly higher performance than Type-GDL/PA MEA.
研究领域:
能源科学
·
材料科学
✓ 已验证
DOI
高影响因子
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