Preprint of "Modifiable Inorganic-Organic Nanofiber Templates for Use in Solid-State Batteries"

This work focuses on the development and optimization of modifiable inorganic–organic templates in the form of submicron fibers and nanofibers for potential use in solid-state batteries. The main objective is to prepare composite structures that combine the advantages of organic polymer fibers and inorganic glassy components. Monodisperse boehmite (AlO(OH)) nanoparticles were used as an inorganic filler. After heat-treatment, they transform into alumina and can subsequently form mullite in the SiO₂–Al₂O₃ system. The fibers were prepared by electrospinning, which allows the production of homogeneous layers with diameters below 1 µm and a high specific surface area. The aim is to achieve a stable and reproducible process and high-quality, homogeneous, compact layers. The results show that heat-treatment at as low as 750 °C leads to the removal of the polymer organic component and the formation of inorganic glassy fibers while preserving the morphology and compactness of the layers. At higher temperatures, further fiber thinning occurs along with gradual mullite crystallization, which was confirmed only after prolonged annealing at 1200 °C. The prepared structures exhibit high thermal stability, porosity, and mechanical integrity, making them suitable for use as functional layers, such as separators or electrodes in solid-state batteries.