Flexible SiO2 nanofiber membrane for thermal insulation

Abstract In recent years, driven by improved energy utilization efficiency and the growing demand for applications in extreme environments, traditional ceramic insulation materials, such as ceramic fiber felt, have shown inherent limitations, particularly brittleness and a lack of flexibility. In contrast SiO 2 nanofibers, owing to their lightweight structure, exceptional flexibility, structural stability, high-temperature resistance, and superior corrosion resistance, have become a focal point in the development of high-performance insulation materials. In this study, a highly spinnable and stable solution was formulated via the sol-gel method, a by optimizing the ratio of TEOS/H 2 O ratio, types and concents of spinning additives, and catalyst HCl/H 2 O content. A flexible SiO 2 nanofiber membrane (SNM), featuring superior flexibility and a degree of fluffy structure, was fabricated using electrospinning technology followed by high-temperature calcination. The SNM exhibits key characteristics such as low density, high mechanical strength (tensile breaking strength of 112.8 kPa, tensile breaking strain of 4.85%), low thermal conductivity (0.02541 W·m −1 ·K −1 , and excellent thermal insulation performance. The developed SiO 2 nanofiber material is a promising candidate for use in lightweight, high-efficiency thermal insulation systems.