Growing bimetallic CoNi-MOF derivatives between MXene layers with hierarchically coral-like interfaces for enhanced electromagnetic wave absorption

Two-dimensional MXenes have gained tremendous attention in the domain of electromagnetic wave absorption (EWA) owing to their outstanding conductivity and unique layered structures. Nevertheless, the disadvantages of easy stacking and non-magnetic properties often lead to incoordinate impedance matching and a single EWA mechanism, making it difficult to obtain optimal EWA performance. Herein, inspired by the hierarchically coral-like architecture, we demonstrated a controllable embedding strategy for in situ growing bimetallic CoNi metal-organic framework (MOF) derived carbon composite materials (CoNi@C) on the interlaminations of layered MXene via solvothermal and subsequent high-temperature annealing processes. The resultant MXene/CoNi@C showed excellent EWA capabilities, which mainly benefitted from a harmonious dielectric-magnetic coupling network with numerous heterointerfaces and porous structures brought about by interlaced CoNi nanorods. As anticipated, an optimal minimum reflection loss of -66.4 dB at 9.5 GHz, corresponding to an effective absorption bandwidth of 3.2 GHz, could be obtained by adjusting the ratios of MXene and CoNi-MOFs. This study will propose a bioinspired structure design strategy for developing high-performance MXene-based absorbers. High-performance MXene-based composites exhibit superior electromagnetic wave absorption capability, owing to the hierarchically coral-like architecture constructed by MXene and bimetallic CoNi-MOFs.