磷酸基团修饰无机粒子填充型有机—无机杂化质子交换膜

发布时间：2018-04-27 08:05

本文选题：燃料电池 + 质子交换膜　；参考：《天津大学》2015年硕士论文

【摘要】：质子传导性能的强化是质子交换膜研究的关键问题。将磷酸基团引入质子交换膜是提高膜质子传导率的有效途径,如何简便有效地实现磷酸基团的固定是磷酸化质子交换膜面临的主要挑战。本研究以无机纳米材料为载体,通过共价键或包裹方式实现磷酸基团的固定,并与高分子膜基质混合制备了磷酸化有机-无机杂化膜。利用磷酸基团优异的导质子性能及其与无机载体间的协同作用,实现质子传导性能的强化。以TiCl4为前驱体,氨基三亚甲基膦酸(ATMP)为磷酸化试剂,在磺化聚醚醚酮(SPEEK)中原位生成粒径约为50 nm的二氧化钛颗粒(TiO2),制备了SPEEK/原位磷酸化二氧化钛杂化膜。ATMP通过稳定的共价键与TiO2连接,均匀分散于SPEEK中。磷酸化TiO2的加入增加了膜内质子传递位点数,提高了质子传递通道的连续性,从而强化了膜的质子传导性能。填充量为6 wt.%的杂化膜在65 oC、饱和湿度下质子传导率达0.334 S cm-1,较纯SPEEK膜高63.7%。利用多巴胺的自聚作用在片状氧化石墨烯(GO)表面包裹一层聚多巴胺,得到多巴胺修饰的GO(DGO),利用迈克尔加成反应将阿仑膦酸负载到DGO表面,制得磷酸化氧化石墨烯(PGO),并填充到Nafion膜基质中制备了Nafion/磷酸化氧化石墨烯杂化膜。PGO的加入提高了膜的吸水保水能力,密集分布于片状GO上的磷酸基团在膜内构建出新型质子传递通道,同时强化了饱和湿度和低湿度下的质子传导性能。填充量2 wt.%的杂化膜,110 oC、饱和湿度下质子传导率可达0.277 S cm-1,为纯Nafion重铸膜的2.2倍;80 oC、40 RH%时,质子传导率达0.0441 S cm-1,为纯Nafion重铸膜的7.6倍。采用水热法合成了具有规则三维孔道结构的MIL-101(Cr),并利用“瓶中船”法以磷酸氢二钠和钨酸钠为单体在其孔道内原位合成磷钨酸,将其填充到SPEEK中制备了SPEEK/MIL101负载磷钨酸杂化膜。由于磷钨酸粒径大于MIL-101(Cr)窗口尺寸,因此可有效防止磷钨酸的流失。MIL-101(Cr)表面的氢键网络和孔道内的磷钨酸在两相界面处与颗粒内部构建出新型传递通道,提高了膜内质子传递通道的连续性,强化了膜的低湿度质子传导性能。填充量9 wt.%的杂化膜在60 oC、40 RH%条件下质子传导率达0.00651 S cm-1,为纯SPEEK膜的7.2倍。
[Abstract]:The enhancement of proton conductivity is a key issue in the study of proton exchange membranes. The introduction of phosphoric acid groups into proton exchange membranes is an effective way to improve the proton conductivity of the membranes. It is a major challenge for phosphorylated proton exchange membranes to fix the phosphoric acid groups simply and effectively. In this study, phosphorylated organic-inorganic hybrid membranes were prepared by covalent bonding or encapsulation of inorganic nanomaterials, and phosphorylated organic-inorganic hybrid membranes were prepared by mixing with polymer membrane matrix. The proton conductivity was enhanced by using the excellent proton conductivity of phosphoric acid group and its synergistic effect with inorganic carrier. TiCl4 was used as precursor and amino trimethylphosphonic acid (TiCl4) as phosphorylation reagent. SPEEK/ in-situ phosphorylated TIO _ 2 hybrid film was prepared by in situ formation of TIO _ 2 particles with a diameter of about 50 nm in sulfonated polyether ether ketone (SPEEK). The SPEEK/ in-situ phosphorylated TIO _ 2 hybrid film was connected with TiO2 through stable covalent bonds and was uniformly dispersed in SPEEK. The addition of phosphorylated TiO2 increases the number of proton transfer sites in the membrane and improves the continuity of the proton transfer channel, thus enhancing the proton conductivity of the membrane. The hybrid membrane filled with 6 wt.% at 65oC has a proton conductivity of 0.334 Scm-1 at saturation humidity, which is 63.7% higher than that of pure SPEEK membrane. Dopamine was coated on the surface of flake graphene oxide by self-polymerization of dopamine to obtain dopamine modified GOD. Alendronic acid was loaded onto the surface of DGO by Michael addition reaction. The phosphorylated graphene oxide (PGO) was prepared, and the Nafion/ phosphorylated graphene oxide hybrid film. PGO was filled in the Nafion membrane matrix to improve the water absorption and water retention of the membrane. A novel proton transfer channel was constructed by concentrated phosphoric acid groups distributed on flake go, which enhanced the proton conductivity at saturation humidity and low humidity. The proton conductivity of the hybrid membrane with 2 wt.% filling can reach 0.277 Scm-1 in saturated humidity. The proton conductivity of pure Nafion recast membrane is 0.0441 Scm-1 and 7.6 times that of pure Nafion recast membrane at 2.2-fold 80oCm-40 RH%. MIL-101CrN with regular three-dimensional pore structure was synthesized by hydrothermal method, and phosphotungstic acid was synthesized in situ by "in-bottle ship" method in its pore channel with disodium hydrogen phosphate and sodium tungstate as monomers. SPEEK/MIL101 supported phosphotungstic acid hybrid films were prepared by filling them into SPEEK. Because the particle size of phosphotungstic acid is larger than the size of MIL-101Cr-window, it can effectively prevent the loss of phosphotungstic acid. MIL-101Cr) surface hydrogen bond network and phosphotungstic acid in the pore to construct a new transfer channel between the two phase interface and the particle interior. The continuity of the proton transfer channel in the membrane is improved and the proton conductivity of the membrane is enhanced. The proton conductivity of the hybrid membrane filled with 9 wt.% was 0.00651 Scm-1 at 60oC ~ (40) RH%, which was 7.2 times of that of pure SPEEK membrane.
【学位授予单位】：天津大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ051.893

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