Enhanced Electron Transport in Fractal Conductive MOF Aerogels Boosting Microwave Absorption

Inherently conductive metal-organic frameworks (c-MOFs) have emerged as promising absorbers of electromagnetic wave (EMW) due to their synergistic combination of intrinsic porosity, high surface area, and tunable topological structures. However, the challenges exist in constructing robust c-MOF monoliths with high electron transport efficiency, which limits their functional applications. Here, electrospun fibers are hydrothermally etched, creating fractal fibers with abundant polar functional groups to induce in situ growth of c-MOFs. Such facilitates the formation of crystal-cluster configurations on fiber surfaces, significantly elevating electron transport efficiency across c-MOFs and reducing overall interfacial contact resistance. The constructed fractal c-MOF aerogels achieve a minimum reflection loss of −61 dB, and an effective absorption bandwidth of 8.24 GHz at an ultra-low density of 0.040 g cm −3 , significantly outperforming existing EMW absorbing c-MOFs. This work demonstrates new c-MOF aerogels for enhanced EMW absorption and multifunctionalities, advancing the engineering of c-MOFs devices.