Porous electrospun fibre mats with with proton conductivity for composite membranes

该项目的目的是通过静电纺丝合成柔性SiO2纤维垫，该纤维垫将被磺酸或苯并咪唑基团官能化以实现高质子传导。为了获得高孔隙率的静电纺丝纳米纤维，将采用不同的策略，以实现质子传导官能团的高负载。首先，分散的SiO2纳米颗粒将用于静电纺丝，以获得多孔SiO2纤维垫，这是由于种间孔隙率。随后，这些多孔纤维垫将用质子传导基团官能化。因此，特别是一个新开发的CVD型方法将用于避免任何机械应力的纤维垫。为了比较和实现高的固有质子传导的所得纤维垫，分散体的介孔SiO2纳米粒子，改性与磺酸基团或苯并咪唑基团，将用于静电纺丝。纳米颗粒的尺寸和孔结构的变化计划优化在低相对湿度下所得纤维垫的质子传导。将通过阻抗谱研究所生产的纤维垫的温度和湿度依赖的质子传导。随后，纤维垫将用Nafion或sPEEK渗透，并研究了复合膜的湿度和温度依赖性质子传导。此外，这些新的纤维垫将被应用于光电化学电池的光电化学水裂解。

Aim of this project is the synthesis of flexible SiO2 fibre mats via electrospinning, which will be functionalized with sulfonic acid or benzimidazole groups for high proton conduction. Different strategies will be pursued to achieve electrospun nanofibers with high porosity, to enable high loading with proton conducting functional groups.Firstly, dispersed SiO2 nanoparticles will be used for electrospinning to achieve porous SiO2 fibre mats due to interparticular porosity. Subsequently, those porous fibre mats will be functionalized with proton conducting groups. Therefore, especially a newly developed CVD-type method will be used to avoid any mechanical stress on the fibre mat.For comparison and to achieve high intrinsic proton conduction of the resulting fibre mats, dispersions of mesoporous SiO2 nanoparticles, modified with either sulfonic acid groups or benzimidazole groups, will be used for electrospinning. Variations of the size and the pore structure of the nanoparticles are planned to optimize the proton conduction of the resulting fibre mats at low relative humidities.The produced fibre mats will be investigated concerning their temperature- and humidity-dependent proton conduction via impedance spectroscopy.Subsequently, the fibre mats will be infiltrated either with Nafion or sPEEK, and the humidity- and temperature-dependent proton conduction of the composite membranes will be investigated. Moreover, these novel fibre mats will be applied in photoelectrochemical cells for photoelectrochemical water splitting.