In Situ Formation of the TiCN Phase in SiBCN Ceramic Aerogels Enabling Superior Thermal and Structural Stability up to 1800 °C

Abstract

Ceramic aerogels show excellent thermal insulation and functional performance for their unique nanoporous structure. However, conventional ceramic aerogels often undergo structural collapse and performance deterioration in high-temperature environments due to sintering, crystallization, and/or phase transition. Here, we designed a TiCN/SiBCN ceramic aerogel in which the TiCN phase was in situ formed through a carbothermal reaction during pyrolysis. Benefiting from its unique pearl-necklace-like structure, the TiCN/SiBCN aerogel exhibits a high specific surface area (248 m2/g), a low thermal conductivity (0.08 W/m·K), and a considerable compressive strength (2.2 MPa). The formation of a stable TiCN phase endows the aerogel with significant resistance to thermal decomposition and crystallization up to 1800 °C. Moreover, the TiCN/SiBCN aerogel retains high surface area and low thermal conductivity after thermal treatment, indicative of the stability and reliability of the nanoporous structure. The TiCN/SiBCN ceramic aerogel with superior thermal and structural stability is an ideal candidate for structural and functional applications in high-temperature environments.

Double-Network MK Resin-Modified Silica Aerogels for High-Temperature Thermal Insulation

“…All stress− strain curves of the MK/SiO 2 aerogels show linear fracture behavior under compressive pressure, which is similar to the pure SiO 2 aerogel, as shown in Figure 6a, indicating their brittleness characteristic. 37,40,41 Differently, for the MK/SiO 2 aerogels, including MK/SiO 2 -0.1 without APTES (Figure S7), the elastic deformation could be over 30%, which is much higher than that of the pure SiO 2 aerogel, indicating the toughening effect of MK in the aerogel. Moreover, the compressive strength of the aerogels significantly increases after the addition of MK resin.…”

A Review of High-Temperature Aerogels: Composition, Mechanisms, and Properties

“…Additionally, Zhang et al [19] formulated a novel Y 2 SiO 5 trigenicity gel with thermal conductivities ranging from 0.029 to 0.05 W/(m•K). Su et al [20] introduced a TiCN/SiBCN ceramic aerogel with a thermal conductivity of 0.08 W/(m•K), while Ding et al [21] prepared ceramic nanofiber-particle composite aerogels, as illustrated in Figure 2a-c.…”

Lightweight polybenzoxazole aerogels with high compressive strength, ultralow dielectric constants, and excellent thermal stability

“…Aerogels are mainly used as thermal protection materials for spacecraft, materials for preventing the impact and vibration of spacecraft during high-speed flight, and structural materials for manufacturing light aerospace spacecraft. [1][2][3][4] Although silica aerogels have excellent thermal insulation properties, their application is severely restricted by their poor mechanical properties and cumbersome drying process. [5][6][7] Therefore, polymer aerogels have garnered increasing attention because they have better mechanical properties, processability, and density than inorganic aerogels.…”