Generation of ultrathin two-dimensional MOF-derived nanocomposites based on ion-exchange strategy with enhanced microwave absorption properties

Metal-organic frameworks (MOFs) materials exhibit inherent advantages in microwave absorption (MA) due to their unique compositional and structural characteristics. However, it remains a significant challenge to systematically elucidate the coordinated effects of component modulation and morphology design on electromagnetic parameters during the complex modification process to enhance the MA performance of MOFs. In this study, the two-dimensional (2D) Co-based MOFs material, layered zeolitic imidazolate framework (ZIF-L), was meticulously selected as a structure design template and combined with an efficient ion-exchange component modulation method, aiming to stimulate the potential advantages between the two in the synergistic modulation of electromagnetic parameters. Specifically, the ion-exchange method enhanced various polarization mechanisms, including interface, dipole, and defect-induced polarizations. Meanwhile, the 2D template facilitates the formation of a robust conductive network on the surface and ensures the high efficiency and uniformity of the ion-exchange process. Ultimately, the resulting material achieved an adequate absorption bandwidth (EAB) of 6.47 GHz at a thickness of 2 mm, a 78% improvement over the untreated sample (EAB = 3.64 GHz). This research not only provides valuable theoretical insights into the application of 2D MOFs materials in MA but also offers innovative perspectives for the design and development of energy-saving and environmentally friendly microwave absorption materials (MAMs).