Preparation and heat-insulating properties of biomorphic ZrO2 hollow fibers derived from a cotton template

Zirconia (ZrO2) fibers are lightweight polycrystalline refractory materials that have long service life, and are suitable for use at ultra-high temperatures (above 1600 degrees C). In this study, biomorphic ZrO2 ceramic fibers were prepared by a simple impregnation method using a zirconic solution using cotton fibers as a biomaterial template. First, cotton fibers were immersed in a zirconyl chloride octahydrate (ZrOCl(2)8H(2)O) solution, which also contained yttrium nitrate hexahydrate [Y(NO3)(3)6H(2)O], stannic chloride (SnCl(4)5H(2)O), and polyvinyl pyrrolidone. The precursor fibers were sintered at different temperatures to produce the final biomorphic ZrO2 ceramic fibers in air. Phase analysis, microstructures, thermoanalysis, and thermal conductivity were investigated. The experimental results show that these ZrO2 ceramic fibers faithfully retain the morphologies of the cotton fibers: parts of the fibers are hollow, allowing greater heat insulation than traditional ZrO2 fibers. In this study, we utilized the morph-genetic theory to prepare insulation material, providing a new and effective way to fabricate materials with excellent heat-insulating properties.