3D Printing-Assisted Honeycomb-Structured Bricklike Aerogels Applied for Infrared Stealth with Good Thermal Management

Delicate structure design with lightweightness and good thermal management for infrared (IR) stealth are two important factors since relying solely on low emissivity surfaces to suppress thermal radiation will lead to heat buildup and erratic performance. Inspired by honeycomb bricks, an IR stealth aerogel of MXene@poly(vinyl alcohol) (PVA)/phase change material (PCM) is prepared by a 3D-printed mold, freeze-drying, and vacuum impregnation. The as-prepared aerogels have excellent properties including high latent heat (105.3 J/g), high compressive modulus (7.844 MPa, 80%), and low emissivity (0.273, 8–14 μm). Benefiting from the design of a honeycomb brick-like structure, which integrated heat insulation, heat absorption, and emissivity reduction strategies, the IR stealth performance is outstanding since they are consistent with the surrounding environment even when exposed to a heat source at 100 and 120 °C for 5 min, and the radiation temperatures when reaching the equilibrium are maintained only 30.9 and 33.8 °C, respectively. The remarkable thermal management and IR stealth properties for long-term use are also confirmed by a Comsol heat transfer simulation. Furthermore, they also possess excellent EMI shielding effect (SE), with SE T = 43.3 dB in the X-band. Therefore, this multimodal stealth composite is expected to be a potential candidate in the field of IR stealth.