燃料电池阴离子交换膜制备及性能研究
发布时间：2018-10-26 20:43
【摘要】：本文设计了一种多官能团离子交换膜制备方法,通过在单体中引入两个官能团提高单位体积内离子交换容量(IEC),从而提高离子传导率。利用密度泛函数(DTF)理论计算反应能垒,计算得到双季铵化单体中活性位点的反应能垒相近,证明分子结构设计合理,双季铵化结构单体制备方法可行。以计算结果为依据,以降冰片烯二酸酐(NA)为原料,通过酰胺化反应、还原反应和季铵化反应制备了双官能团降冰片烯衍生物单体,采用开环易位聚合(ROMP)制备了季铵型聚降冰片烯系列阴离子交换膜。通过核磁氢谱(1HNMR)和红外光谱(FTIR)对降冰片烯衍生物单体和聚合物(L-x、AEM-x)结构进行了表征,对制备的五种类型的离子交换膜进行各项性能进行了测试,发现交联型膜比线型膜具有更强的机械强度和更低的吸水溶胀率,这主要是因为交联单体的引入使聚合物线型结构连接成网状结构,使分子结构更加紧密,随着交联单体引入,拉伸强度从6.19 MPa提高到15.18MPa,溶胀率从29.26%降到12.45%。分析电化学性能发现,AEM-F膜的氢氧根离子传导率在25℃为64.79 mS·cm-1,接近同等条件下PEMNafion 117的质子传导率,远高于同类型阴离子交换膜(AEMs)氢氧根离子(OH-)的离子传导率。选取AEM-F膜制备膜电极(MEA)并组装单电池,电池开路电压在1.02- 1.06V之间,表现出优异的气体阻隔性,最大功率密度达到151.36 mW·cm-2。然后结合催化剂用量、气体流量和电池温度下电池的极化曲线和功率密度测试数据讨论了电池性能的影响因素。为了研究OH-传导机理,通过分子动力学(MD)方法模拟AEMs的使用环境,计算离子交换膜内分子作用关系和氢氧根离子的运动轨迹,进一步分析膜内的微相结构和氢氧根离子的传输机理,从而对实验现象进行解释并对以后实验起到一定的指导作用。
[Abstract]:In this paper, a preparation method of multifunctional ion-exchange membrane is designed. By introducing two functional groups into the monomer, the ion exchange capacity (IEC),) is increased in unit volume to improve the ionic conductivity. The reaction energy barrier was calculated by using the (DTF) theory of density universal function, and the reaction energy barrier of the active site in the double quaternary ammonium monomer was calculated. It is proved that the molecular structure design is reasonable and the preparation method of the double quaternary ammonium monomer is feasible. Based on the calculation results, difunctional norbornene derivatives were prepared by amidation, reduction and quaternary ammonium reaction from norbornic anhydride (NA). A series of quaternary ammonium polynorbornene anion exchange membranes were prepared by ring-opening translocation polymerization (ROMP). The structures of norbornene derivatives monomer and polymer (L-xAEM-x) were characterized by 1HNMR and (FTIR), and the properties of five kinds of ion-exchange membranes were tested. It is found that the cross-linked membrane has stronger mechanical strength and lower water swelling rate than the linear membrane, which is mainly due to the introduction of the cross-linked monomer to make the polymer linear structure connect to the network structure, and make the molecular structure more compact, with the introduction of the cross-linked monomer. The tensile strength was increased from 6.19 MPa to 15.18 MPA, and the swelling rate decreased from 29.26% to 12.45 MPA. By analyzing the electrochemical properties, it is found that the hydrogen oxygen ion conductivity of AEM-F membrane is close to the proton conductivity of PEMNafion 117 at 25 鈩，
本文编号：2296893
[Abstract]:In this paper, a preparation method of multifunctional ion-exchange membrane is designed. By introducing two functional groups into the monomer, the ion exchange capacity (IEC),) is increased in unit volume to improve the ionic conductivity. The reaction energy barrier was calculated by using the (DTF) theory of density universal function, and the reaction energy barrier of the active site in the double quaternary ammonium monomer was calculated. It is proved that the molecular structure design is reasonable and the preparation method of the double quaternary ammonium monomer is feasible. Based on the calculation results, difunctional norbornene derivatives were prepared by amidation, reduction and quaternary ammonium reaction from norbornic anhydride (NA). A series of quaternary ammonium polynorbornene anion exchange membranes were prepared by ring-opening translocation polymerization (ROMP). The structures of norbornene derivatives monomer and polymer (L-xAEM-x) were characterized by 1HNMR and (FTIR), and the properties of five kinds of ion-exchange membranes were tested. It is found that the cross-linked membrane has stronger mechanical strength and lower water swelling rate than the linear membrane, which is mainly due to the introduction of the cross-linked monomer to make the polymer linear structure connect to the network structure, and make the molecular structure more compact, with the introduction of the cross-linked monomer. The tensile strength was increased from 6.19 MPa to 15.18 MPA, and the swelling rate decreased from 29.26% to 12.45 MPA. By analyzing the electrochemical properties, it is found that the hydrogen oxygen ion conductivity of AEM-F membrane is close to the proton conductivity of PEMNafion 117 at 25 鈩，
本文编号：2296893
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