2D/2D coupled MOF/Fe composite metamaterials enable robust ultra-broadband microwave absorption.

The combination between macroscopic structure designs and microscopic material designs offers tremendous possibilities for the development of advanced electromagnetic wave (EMW) absorbers. Herein, we propose a metamaterial design to address persistent challenges in this field, including narrow bandwidth, low-frequency bottlenecks, and, particularly, the urgent issue of robustness (i.e., oblique, and polarized incidence). Our absorber features a semiconductive metal-organic framework/iron 2D/2D assembly (CuHT-FCIP) with abundant crystal/crystal heterojunctions and strong magneto-electric coupling networks. This design achieves remarkable EMW absorption across a broad range (2 to 40 GHz) at a thickness of just 9.3 mm. Notably, it maintains stable performance against oblique incidence (within 75°) and polarizations (both transverse electric and transverse magnetic). Furthermore, the absorber demonstrates high specific compressive strength (201.01 MPa·cm 3 ·g -1 ) and low density (0.89 g·cm -3 ). This advancement holds promise for developing robust EMW absorbers with superior performance.