Synthesis and characterization of sol-gel derived lanthanum zirconate ceramic aerogels toward ultralow thermal conductivity

La2Zr2O7 ceramic aerogels (LZO CAs) were successfully fabricated via sol-gel method followed by heat treatment process. The morphology, microstructure, and phase composition of the as-prepared samples were systematically studied using various technological means. The results indicated that the as-prepared LZO CAs present a typical three-dimentional (3-D) porous network with a single-phase pyrochlore crystal structure. In addition, the as-prepared LZO CAs presented high specific surface area of 594.85 m2/g, low thermal conductivity of 0.033 W/(m·K) at room temperature, and remarkable high temperature heat-insulating property. This work offers a novel strategy for the development of other rare-earth zirconates ceramic aerogels which can be used as high temperature insulations.