Strong, flexible, and thermal-stable Gd2Zr2O7 nanofiber membranes with excellent thermal insulation performance

Abstract

The demands for high-temperature resistant thermal insulation materials in the realms of aviation, aerospace, and military technology are constantly escalating. The development of thermal insulation materials capable of stable operation at high temperatures above 1200°C has become a significant research direction. In response, Gd₂Zr₂O₇ has emerged as a promising flexible thermal insulation material due to its low thermal conductivity, high melting point and thermal stability. This study addresses the challenge of fabricating Gd₂Zr₂O₇ nanofibers with superior mechanical properties and high-temperature stability. Defect fluorite-structured Gd₂Zr₂O₇ nanofibers were prepared by using the sol-gel method and electrospinning technique. The resulting nanofibers exhibited small grain size (84.5 nm@1300°C), dense structure and high tensile strength (1.69 MPa@1100°C), excellent bending fatigue resistance (recoverable bending strain up to 80%). Additionally, the nanofibers demonstrated high strength retention (68%) and low area shrinkage (<2%) after heat-treatment at 1300°C, indicating excellent high-temperature stability. The thermal conductivity of Gd₂Zr₂O₇ nanofiber membranes was very low (26.2 mW·m^-1·K^-1@1300°C), showcasing outstanding high-temperature insulation property. Therefore, the simple and effective preparation method proposed in this study, along with the superior thermal insulation performance of the Gd₂Zr₂O₇ nanofibers, shows great potential for large-scale practical applications.