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《膜科学与技术》2017,(4)
采用无水对氨基苯磺酸(SA)对氧化石墨烯(GO)进行了磺化,并得到磺化氧化石墨烯(SGO),将磺化聚醚醚酮(SPEEK)膜包裹在SGO纸的两侧,制备了SPEEK/SGO/SPEEK膜作质子交换膜(PEM).通过膜性能表征可知,与SPEEK和SPEEK/GO/SPEEK膜相比,SPEEK/SGO/SPEEK膜的离子交换容量(IEC)提高,质子传导活化能(Ea)明显降低,甚至与Nafion*112膜相近,而其甲醇渗透率远低于Nafion*112膜.将膜组装成直接甲醇燃料电池(DMFC),经测试电池性能得到SPEEK/SGO/SPEEK组装的DMFC的最高能量密度在80℃和1mol/L甲醇浓度时可达42.1mW/cm~2,比商业Nafion*112膜组装的电池的最高能量密度高35.4%,明显优于SPEEK和SPEEK/GO/SPEEK膜,且电池稳定性良好,证明SPEEK/SGO/SPEEK膜在PEM的应用方面具有很大的潜力. 相似文献
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聚乙烯醇膜的阻醇及导电性能研究(Ⅰ)热处理聚乙烯醇膜 总被引:5,自引:0,他引:5
直接甲醇质子交换膜燃料电池(DMFC)中甲醇的穿透问题是阻碍其发展的瓶颈,为提高膜的阻醇性能,采用在渗透蒸发领域广泛使用且具有良好分离效果的聚乙烯醇(PVA)为原料,制备了热处理PVA膜,对其阻醇及质子导电能力进行了研究。PVA膜的阻醇效果较目前在DMFC中广泛使用的Nafion全氟磺酸膜的有明显提高。但其自身不具有质子导电能力。需外加电解质溶液以提高其电导率。 相似文献
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以聚乙烯醇(PVA)、磷钨酸(PWA)和氧化铝(Al2O3)溶胶为原料,制备得到PVA—PWA—Al2O3无机-有机复合质子交换膜,测定了膜的电导率、含水率、溶胀度和甲醇透过系数等性质.测试结果表明,该复合膜具有较高的导电率和较好的阻醇效果,室温下测得电导率最高达到1.162S/cm,甲醇透过系数在10^-7cm^2/s左右.复合膜中PWA含量增加,膜的电导率、含水率、溶胀度和甲醇透过系数都有所上升;膜中Al2O3含量增加,膜的电导率、含水率、溶胀度提高,但甲醇渗透系数稍有下降. 相似文献
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聚合物 填料复合材料以其低廉的成本、简便的成型工艺、良好的气密性和耐腐蚀性而被认为是直接甲醇燃料电池(DMFC)双极板的适用材料之一。本文对模压成型的聚合物 填料复合材料进行了测试。四探针测试仪的测试结果显示材料的导电性良好,并且沿厚度方向的电导率高于沿平面方向的电导率。模拟DMFC阳极和阴极的内部环境以检验材料的耐腐蚀性,结果表明,该材料在 DMFC的工作环境中无明显腐蚀现象。材料的气密性极佳。此种复合材料满足DMFC对于低成本双极板的要求。 相似文献
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PVA-PWA-Al2O3无机-有机复合质子交换膜的研究 总被引:3,自引:0,他引:3
以聚乙烯醇(PVA)、磷钨酸(PWA)和氧化铝(Al2O3)溶胶为原料,制备得到PVA-PWA-Al2O3无机-有机复合质子交换膜,测定了膜的电导率、含水率、溶胀度和甲醇透过系数等性质.测试结果表明,该复合膜具有较高的导电率和较好的阻醇效果,室温下测得电导率最高达到1.162 S/cm,甲醇透过系数在10-7cm2/s左右.复合膜中PWA含量增加,膜的电导率、含水率、溶胀度和甲醇透过系数都有所上升;膜中Al2O3含量增加,膜的电导率、含水率、溶胀度提高,但甲醇渗透系数稍有下降. 相似文献
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聚乙烯醇膜的阻醇及导电性能(Ⅱ)戊二醛交联聚乙烯醇膜 总被引:3,自引:0,他引:3
为提高直接甲醇燃料电池(DMFC)用膜的阻醇性能,采用在渗透蒸发领域广泛使用且具有良好分离效果的聚乙烯醇(PVA)为主要材料,制备了戊二醛(GA)交联PVA膜,考察了此类膜的阻醇及质子导电能力。PVA(GA)膜的阻醇效果较目前在DMFC中广泛使用的Nation膜有显著提高,但其自身不具有质子导电能力,需外加电解质溶液以提高其电导率。 相似文献
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本文在聚醚醚酮(PEEK)磺化反应制备相同磺化度的磺化聚醚醚酮(SPEEK)基础上,采用不同的溶剂通过溶液法制备一系列SPEEK质子交换膜,采取交流阻抗法、扩散池法和溶胀法分别评价其导质子能力、阻醇性能和溶液稳定性,探讨溶剂种类对SPEEK质子交换膜性能的影响规律.试验结果表明溶剂对所制备膜的导质子能力和阻醇性能影响依赖于溶剂分子与SPEEK中磺酸基团的相互作用,若存在越强作用,膜的导质子能力越弱,而阻醇性能越高.此外,溶剂种类对膜的吸水溶胀性能存在较小的影响,对膜表面的微孔形态存在明显的影响,并与膜的导质子能力及阻醇性能存在对应关系.综合比较不同溶剂制备膜的导质子能力、阻醇性能和吸水溶胀性能,DMAc是优于DMF和DMSo的制膜溶剂. 相似文献
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直接甲醇燃料电池用磷酸掺杂PAN复合膜的研究 总被引:3,自引:0,他引:3
本文研究了聚丙烯腈-磷酸(PAN-xH3PO4)复合质子交换膜的结构、聚合物与酸之间的相互作用、甲醇渗透性能以及质子导电性能。结果表明。PAN-xH3PO4复合膜与Nation膜的甲醇渗透率相差不大。但是比聚丙烯腈膜的甲醇渗透率高两个数量级左右,而且随甲醇浓度增加而增加;PAN-xH3PO4复合膜具有较好的质子导电能力。电导率随频率(时间)的变化很小,其质子导电性能主要依赖于聚合物与酸的相互作用。 相似文献
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Self‐Healing Proton‐Exchange Membranes Composed of Nafion–Poly(vinyl alcohol) Complexes for Durable Direct Methanol Fuel Cells
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Yixuan Li Liang Liang Changpeng Liu Yang Li Wei Xing Junqi Sun 《Advanced materials (Deerfield Beach, Fla.)》2018,30(25)
Proton‐exchange membranes (PEMs) that can heal mechanical damage to restore original functions are important for the fabrication of durable and reliable direct methanol fuel cells (DMFCs). The fabrication of healable PEMs that exhibit satisfactory mechanical stability, enhanced proton conductivity, and suppressed methanol permeability via hydrogen‐bonding complexation between Nafion and poly(vinyl alcohol) (PVA) followed by postmodification with 4‐carboxybenzaldehyde (CBA) molecules is presented. Compared with pure Nafion, the CBA/Nafion–PVA membranes exhibit enhanced mechanical properties with an ultimate tensile strength of ≈20.3 MPa and strain of ≈380%. The CBA/Nafion–PVA membrane shows a proton conductivity of 0.11 S cm?1 at 80 °C, which is 1.2‐fold higher than that of a Nafion membrane. The incorporated PVA gives the CBA/Nafion–PVA membranes excellent proton conductivity and methanol resistance. The resulting CBA/Nafion–PVA membranes are capable of healing mechanical damage of several tens of micrometers in size and restoring their original proton conductivity and methanol resistance under the working conditions of DMFCs. The healing property originates from the reversibility of hydrogen‐bonding interactions between Nafion and CBA‐modified PVA and the high chain mobility of Nafion and CBA‐modified PVA. 相似文献
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A novel composite membrane was prepared by incorporation of silica-included phosphotungstic acid (PWA) additive into perfluorosulfonic
acid (PFSA) followed by solution casting. Physico-chemical properties of the composite membranes were studied by Fourier transform
infrared (FT-IR) spectroscopy, thermogravimetry analysis (TGA), water uptake and swelling ratio. The results of FT-IR and
TGA illustrated the stability of the PWA-silica additive in the PFSA matrix. Lower PWA-silica additive loading (2.5 and 5 wt%)
in the composite membranes helped to inhibit methanol crossover and enhance the proton conductivity. However, higher additive
content shows decrease in both methanol resistance and proton conductivity. 相似文献
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Gabriela Guevara-Carrion Jadran Vrabec Hans Hasse 《International Journal of Thermophysics》2012,33(3):449-468
Transport properties of ammonia and of the binary mixture ammonia + methanol are predicted for a broad range of liquid states
by molecular dynamics (MD) simulation on the basis of rigid, non-polarizable molecular models of the united-atom type. These
models were parameterized in preceding work using only experimental vapor-liquid equilibrium data. The self- and the Maxwell-Stefan
(MS) diffusion coefficients as well as the shear viscosity are obtained by equilibrium MD and the Green-Kubo formalism. Non-equilibrium
MD is used for the thermal conductivity. The transport properties of liquid ammonia are predicted for temperatures between
223 K and 473 K up to pressures of 200 MPa and are compared to experimental data and correlations thereof. Generally, good
agreement is achieved. The predicted self-diffusion coefficient as well as the shear viscosity deviates on average by less
than 15 % from the experiment and the thermal conductivity by less than 6 %. Furthermore, the self- and the MS transport diffusion
coefficients as well as the shear viscosity of the liquid mixture ammonia + methanol are studied at different compositions
and compared to the available experimental data. 相似文献