Rational Design of a Core-Shelled Ti₃AlC₂@La₂Zr₂O₇ Composite for High-Temperature Broadband Microwave Absorption

Microwave-absorbing materials adapting to high temperatures and harsh environments are in great demand. Herein, a core-shelled Ti₃AlC₂@La₂Zr₂O₇ (TAC@LZO) composite was designed and fabricated by encapsulating the La₂Zr₂O₇ (LZO) thermal insulation ceramic on the surface of highly conductive Ti₃AlC₂ (TAC) via chemical coprecipitation and subsequent heat treatment. The continuous LZO ceramic coating on the surface improved the oxidation resistance of the composite at 600 °C and modulated its dielectric properties. The TAC@LZO composite exhibited an excellent microwave absorption performance within the temperature range of 25-600 °C, minimum reflection loss (RL_min) < -55 dB, and effective absorption bandwidth (EAB, RL < -10 dB) of 4 GHz. This work presents an effective approach for developing stable high-temperature microwave absorbers from thermal insulation ceramics.