Bamboo‐Inspired Ceramic Fiber Aerogels With Tubular Through‐Hole Channels: Effects of Precursor and Overall Porosity

ABSTRACT Ceramic aerogels fabricated through the polymer‐derived ceramic route have garnered significant attention in high‐temperature thermal insulation. However, the practical application of conventional ceramic aerogels was seriously limited due to thermal shrinkage and structural damage during pyrolysis. To effectively tackle this issue, drawing inspiration from bamboo culm wall, ceramic fiber aerogels featuring tubular through‐hole channels were rationally fabricated. This unique microstructure provided ample buffering space for volume shrinkage during pyrolysis, guiding the material to undergo radial inward shrinkage within the channels instead of random deformation, which significantly enhanced its shrinkage resistance. The feasibility of this methodology was verified by the previous work, while the effects of precursor and overall porosity on the performance of the aerogels remained largely unexplored. In this work, the ceramic fiber aerogels were separately fabricated by different precursors, and the overall porosity of the aerogels was regulated by adjusting the electrospinning duration. Finite element simulation was implemented to quantitatively elucidate the stress distribution and heat transfer mechanisms. Precursor composition exerted a considerable impact on the properties of the aerogels, determining their intrinsic nature and core–shell interfacial interaction strength. Moreover, a moderate rise in the overall porosity significantly elevated their thermal insulation performance.