SiC nanowires (SiC NWs) possess both high thermal stability of SiC ceramic and one‐dimensional nanoscale features, which makes them highly attractive as reinforcements in ceramics or building units in resilient ceramic nanowires aerogels (NWAs) as well as blocks for electronic nanodevices. Understanding the oxidation behavior of SiC NWs at high temperatures is essential for their practical applications. Herein, we investigated the oxidation behavior of SiC NWs at 900–1200°C in air. Two oxidation stages were found, including an initial stage controlled by the reaction between oxygen and SiC at the SiO2/SiC interface and a subsequent oxygen diffusion–dependent stage. The oxide scale thickness was strongly influenced by the radius of the SiC NWs. With the increase of the NW radius from 40 to 120 nm, the oxidation activation energy of the oxidation process increases from 84.05 to 98.32 kJ/mol. The thermal insulation performances of SiC NWA, which is composed of SiC NWs, have been improved after oxidation. The evolution of the thermal insulation performance of SiC NWA during oxidation is consistent with the trends of the growth of the amorphous oxide layer, which indicates that exploring the oxidation kinetics is of great significance in understanding the high‐temperature behavior of SiC NW‐based materials. The present work provides insight into exploring the size effects on oxidation of SiC NWs, which may be helpful to further understanding the high‐temperature applications of SiC NWA.

Pursuing novel thermal barrier–coating materials with lower thermal conductivity and high‐temperature stability can simultaneously improve the working efficiency and service temperature of a gas turbine. In this study, a series of high‐entropy RE2(Y0.2Yb0.2Nb0.2Ta0.2Ce0.2)2O7 (RE = La, Nd, Sm, Gd, Dy, and Er) oxides were prepared though solid‐state reaction. Through tuning the rare‐earth cations, an order–disorder transition occurs from certain partially ordered weberite structure (C2221) to disordered defective fluorite structure (Fm3¯$\bar{3}$m). All the high‐entropy RE2(Y0.2Yb0.2Nb0.2Ta0.2Ce0.2)2O7 oxides possess low thermal conductivity in the range of 0.91–1.34 W m−1 K−1 at room temperature, which can be attributed to increased lattice anharmonicity and disorder, resulting in additional phonon scattering. Herein, we proved that the incorporation of heterovalent cations at B‐sites in high‐entropy A2B2O7 crystals is an effective strategy to reduce the thermal conductivity without compromising the decrease of oxygen vacancy. Moreover, the high‐entropy RE2(Y0.2Yb0.2Nb0.2Ta0.2Ce0.2)2O7 oxides show the relatively higher thermal expansion coefficients of 10.3–10.7 × 10−6°C−1 and excellent phase stability at elevated temperatures.

Ceramic aerogels are attractive for their promising applications in thermal insulation, ultrafiltration, catalysis, and many other areas, owing to their high porosity, low density, high specific surface area, low thermal conductivity, and thermal stability. However, the practical applications of conventional ceramic aerogels are usually impeded by brittleness. Resilient ceramic aerogels overcame the brittleness of conventional ceramic aerogels and realized reversible compressibility, but they usually show brittleness under tensile stress and limited load‐bearing ability. In this short review paper, we reviewed the strategies to modify the mechanical properties of resilient ceramic aerogel. These strategies were achieved through tuning the deformation and moving ability of the nanowire building blocks and the deformation resistance provided by the aerogel architecture. Perspectives for further modifying the mechanical properties of resilient ceramic aerogel are also discussed.

Integrating multiple functions such as high electromagnetic (EM) wave absorption, thermal insulation, and resilience into one material is critical, especially for applications in harsh environment. SiC ceramic has received considerable attention as high‐temperature wave absorber, but its applications are limited by common wave absorption performance and brittleness of ceramics. Here by incorporating SiO2 with SiC in a unique three‐dimensional network structure, SiOC/SiC foam consisting of abundant SiOC thin flakes interconnected by numerous long interweaving SiC nanowires have been prepared. The foam shows high EM wave absorption with minimum reflection loss of −30.23 dB, broad effective absorption bandwidth of 5.4 GHz, and a nearly complete compressive resilience from 10% strain. Besides, the foam displays high‐temperature resistance up to 1400°C in air and good thermal insulation performance. Such multifunctional material is promising for applications in advanced aerospace industry under extreme conditions.

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