Porous electrospun fibre mats with with proton conductivity for composite membranes

• Applicant: Professor Dr. Roland Marschall
• Subject Area: Solid State and Surface Chemistry, Material Synthesis ; Physical Chemistry of Solids and Surfaces, Material Characterisation
• Term: from 2019 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 413271034

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.

• DFG Programme: Research Grants