Dual bionics of structure and preparation: Gradient architectured carbon/ceramic composite as light as water but bearing ultra-high temperature max to 2500 °C

The ultra-lightweight and high-performance materials have always been in demand for modern technology, especially in the aerospace industry. A rational solution to learning from nature is constructing gradient architectures, which remains a great challenge. Inspired by the cellulose fibrous structure in trees for absorbing nutrition from the soil, a convenient strategy based on capillary adsorption is proposed to achieve autonomous and controllable transportation of ceramic inside carbon fabric. Using this method, we obtained gradient architectured carbon/ceramic composites with density at 1.0 and 1.4 g/cm³, which endured 2000 °C and 2500 °C over 300s respectively. The excellent thermal endurance with ultralow density realized great performance as thermal protection material. The ultralight carbon/ceramic composite offered competitive thermal insulation performance with a back temperature below 120 °C while enduring 1300∼1400 °C for 30 min on the front side. This dual bionics of structure and preparation provides flexible designing and constructing gradient architecture composites based on a fibrous framework.