Fiber Aerogels: Bridging Multi‐Scale Structure Design With Mechanical and Thermal Properties Enhancement

ABSTRACT Recent decades have witnessed a significant surge in research interest toward aerogels, driven by their exceptional physicochemical properties, including ultralow density, high porosity, and large specific surface area. However, conventional aerogels suffer from inherent brittleness, particulate release, and restricted service temperatures, severely impeding applications in complex structures or extreme environments. To overcome these constraints, researchers have innovatively replaced gel particles with ceramic fibers as building blocks, integrating the advantages of ceramic materials with fibrous architectures. This paradigm shift has yielded ceramic fiber aerogels (CFAs) characterized by superior flexibility and stable performance across a wide range of temperatures, demonstrating significant potential for thermal management under extreme conditions. This review comprehensively examines recent progress, optimization strategies, and application prospects of CFA‐based thermal insulation materials. We begin by outlining the classification of CFAs along with their respective advantages and limitations. Subsequently, we detail the characteristic features and synthetic methodologies of current predominant CFA structures. Building upon two pivotal performance metrics for thermal protection materials, mechanical robustness and thermal insulation efficacy, we systematically analyze state‐of‐the‐art optimization strategies for enhancing CFA performance. Furthermore, we highlight emerging applications of CFA thermal insulators in critical domains, including: battery thermal management (with focus on thermal runaway mitigation), personal thermal management systems, energy‐efficient building insulation, and aerospace thermal protection systems. Finally, we conclude with perspectives on future research trajectories and potential breakthroughs in the CFA domain.