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1.
Developing a low-cost and effective proton-conductive electrolyte to meet the requirements of the large-scale manufacturing of proton exchange membrane (PEM) fuel cells is of great significance in progressing towards the upcoming “hydrogen economy” society. Herein, utilizing the one-pot acylation polymeric combination of acyl chloride and amine precursors, a polyamide with in-built -SO3H moieties (PA-PhSO3H) was facilely synthesized. Characterization shows that it possesses a porous feature and a high stability at the practical operating conditions of PEM fuel cells. Investigations of electrochemical impedance spectroscopy (EIS) measurements revealed that the fabricated PA-PhSO3H displays a proton conductivity of up to 8.85 × 10−2 S·cm−1 at 353 K under 98% relative humidity (RH), which is more than two orders of magnitude higher than that of its -SO3H-free analogue, PA-Ph (6.30 × 10−4 S·cm−1), under the same conditions. Therefore, matrix-mixed membranes were fabricated by mixing with polyacrylonitrile (PAN) in different ratios, and the EIS analyses revealed that its proton conductivity can reach up to 4.90 × 10−2 S·cm−1 at 353 K and a 98% relative humidity (RH) when the weight ratio of PA-PhSO3H:PAN is 3:1 (labeled as PA-PhSO3H-PAN (3:1)), the value of which is even comparable with those of commercial-available electrolytes being used in PEM fuel cells. Additionally, continuous tests showed that PA-PhSO3H-PAN (3:1) possesses a long-life reusability. This work demonstrates, using the simple acylation reaction with the sulfonated module as precursor, that low-cost and highly effective proton-conductive electrolytes for PEM fuel cells can be facilely achieved.  相似文献   
2.
利用3,3,4,4-四氟二苯砜、十氟联苯、6F-双酚A及6,13-双三蝶烯二酚,通过亲核取代共聚及后磺化方法制备了2个系列不同磺化度的磺化双三蝶烯型聚芳醚砜,并通过氢核磁共振波谱(1H NMR)对其化学结构进行了表征.研究发现,所得磺化聚芳醚砜均表现出了优异的热稳定性.此类膜材料具有优良的机械性能、尺寸稳定性、氧化稳定性及高温低湿度条件下高的质子传导率.透射电子显微镜的结果表明,聚合物主链中大量氟原子的引入显著改善了聚合物的相分离结构,并且随着聚合物主链中氟含量的增加,亲水区域明显增大.这也是含氟磺化双三蝶烯型聚芳醚砜质子交换膜材料在高温低湿度条件下具有高质子传导率的主要原因.  相似文献   
3.
本文合成并表征了一种水溶性七甲川吲哚菁染料,测试了染料在不同溶剂和不同浓度的表面活性剂十六烷基三甲基溴化铵(CTAB)中的吸收和荧光光谱性质.结果表明:染料的最大吸收和荧光发射光谱值(乙醇中)分别是796nm和813nm.随着溶剂的黏度增大,染料的荧光强度逐渐减弱.CTAB形成胶束前,随着CTAB浓度的增大,染料的吸收...  相似文献   
4.
染料中间体间氨基-N-取代-苯磺酰胺的合成研究   总被引:2,自引:0,他引:2  
以间氨基苯磺酸为原料,经乙酰化保护氨基,用氯磺酸/氯化亚砜将磺箕转变为磺酰氯,再分别与氨基G酸、吐氏酸、γ-酸、6-氨基-1,3-萘二磺酸、5,6-二氨基-1,3-萘二磺酸胺化缩合,水解去乙酰基,较高收率地合成了间氨基-N-取代-苯磺酰胺类染料中间体。产物结构经元素分析、红外、核磁和质谱确证。  相似文献   
5.
钒液流电池是近年来发展最为迅猛的储能电池之一。隔膜作为钒电池的重要组成部分直接关系到钒电池的转化储能效率和使用寿命。本文综述了近年来钒电池用隔离膜的发展现状。全氟磺酸质子交换膜(Nafion膜)作为当前使用最为广泛的隔膜,从传导机理、交换机理和表面涂覆、交联、复合等表面改性技术方面入手做了深入的研究,并对比分析了各种改性方法的优缺点。对磺化的特种工程塑料为主的非氟耐热型质子交换膜和功能化的聚烯烃隔膜在钒电池中的当前进展做了全面总结,并对钒液流电池用电池隔膜的发展方向做了展望。  相似文献   
6.
The functionalized multi‐wall carbon nanotube with 1,2‐naphthoquinone‐4‐sulfonic acid sodium (Nq‐MWNT) was fabricated by a simple and low‐cost method. Techniques of scanning electron microscope (SEM) with energy dispersive X‐ray (EDX) analysis, fourier transform infrared spectroscopy (FT‐IR), ultraviolet visible spectroscopy (UV‐vis) and cyclic voltammetry (CV) were used to characterize the property of the Nq‐MWNT. The results showed that the MWNT with high functionalization of Nq can be obtained using this simple method. The Nq‐MWNT modified carbon paste electrode (Nq‐MWNT/CPE) was fabricated by drop‐casting technique. The resulted modified electrode was tested successfully to detection D‐penicillamine (D‐PA) and captopril (CAP) in an aqueous solution. It is found that D‐PA and CAP participate in Michael addition reaction with Nq on MWNT to form the corresponding thioquinone derivative. The reoxidation of adducts at a potential of less positive than D‐PA and CAP at the surface of the bare CPE leads to an increase in the oxidative current, which is proportional to the concentration of D‐PA and CAP. The catalytic response showed a wide linear range (3‐200 μM and 1‐130 μM for D‐PA and CAP, respectively) as well as its experimental limit of detection can be achieved 0.8 μM, and 0.4 μM for D‐PA and CAP, respectively. The modified electrode for D‐PA and CAP determination is of the property of simple preparation, good stability and high sensitivity. Furthermore, the fabricated electrode was used to determine the content of D‐PA and CAP in the tablet, suggesting the good accuracy of the method.  相似文献   
7.
以十六胺插层磷酸锆为原料, 利用十二烷基二甲基苄基氯化铵为导向模板剂, 通过正硅酸乙酯和巯丙基三甲氧基硅烷的层间共水解缩聚, 并结合双氧水对巯丙基的熏蒸氧化, 制备了磺酸基修饰的硅柱磷酸锆材料。通过XRD、SEM、N2吸附-脱附和FT-IR等方法对柱撑材料进行了结构表征。结果表明, 通过调变预撑剂和模板剂中的碳链长度可以优化材料的柱撑结构和孔结构, 磺酸基修饰的材料孔径分布在2.17 nm左右, 比表面积可达163 m2·g-1, 且保留有规整有序的柱撑磷酸锆层板结构。磺酸基的修饰则成功调变了材料的酸位性质, Brönsted酸量最高可达2.71 mmol·g-1, 总酸量可达5.20 mmol·g-1。利用柠檬酸与正丁醇的酯化反应为探针反应, 由于磺酸基修饰的硅柱磷酸锆材料具有独特的空间反应效应和较为丰富的Brönsted酸位, 酯化反应转化率最高可达95.74%。  相似文献   
8.
The aromatic aldehydes underwent cross aldol condensation with cycloalkanones in the presence of a catalytic amount of nanoporous silica-based sulfonic acid (SiO2-Pr-SO3H) under solvent-free conditions to afford the corresponding α,α’-bis(substituted benzylidene)cycloalkanones in excellent yields with short reaction time without any side reactions. This method is very general, simple and environmentally friendly in contrast with other existing methods. SiO2-Pr-SO3H was proved to be an efficient heterogeneous solid acid catalyst, which could be easily handled and removed from the reaction mixture by simple filtration, and also recovered and reused without loss of reactivity.  相似文献   
9.
Post‐synthesis modification of MIL‐101(Cr)‐NO2 was explored in order to decorate the organic backbone by propyl‐sulfonic groups, with the aim to incorporate mobile and acidic protons for solid‐state proton electrolyte applications. The resulting solid switched from insulating towards proton superconductive behavior under humidity, while the conductivity recorded at 363 K and 95 % relative humidity reached 4.8×10?3 S cm?1. Propitiously, the impregnation of the material by strong acidic molecules (H2SO4) further boosted the proton conductivity performances up to the remarkable σ value of 1.3×10?1 S cm?1 at 363 K/95 % RH, which reaches the performances of the best proton conductive MOF reported so far.  相似文献   
10.
梁强  韩爱霞  牛丽红  张复实 《有机化学》2004,24(9):1052-1056
以空心酞菁(H2Pc)为原料,采用取代基转化法,经过氯磺酰化和酯化合成了空心酞菁磺酰氯和空心酞菁磺酸对甲氧基苯酯,经元素分析,1H NMR,IR,UV-Vis等方法,确定了空心酞菁磺酰氯和空心酞菁磺酸对甲氧基苯酯的组成分别为H2Pc(SO2Cl)4和H2Pc(SO2-p-OC6H4OCH3)4.结果表明,此两种产物在空心酞菁的苯环上引入取代基后,长波吸收增强,溶解度高,热稳定性良好.  相似文献   
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