Synthesis of a Leaf-Like Co/C Nanosheet for Efficient Microwave Absorption.

Elaborate engineering of the microstructure of electromagnetic (EM) absorption materials affords infinite potential for achieving superior EM wave absorption performance. In this work, a leaf-like Co/C nanosheet was rationally fabricated by a facile pyrolysis of a CoZn-based zeolitic imidazolate framework-L (Co/Zn-ZIF-L) precursor. Herein, Co nanoparticles (NPs) are uniformly confined in the leaf-like porous carbon matrix, forming attractive heterostructures. A suitable 2D morphology and Co/C binary components endow the composite with superior impedance matching and synergetic EM losses for excellent microwave absorption and radar stealth performance. When the filler content is as low as 25 wt %, the strong absorption intensity of -47.6 dB is reached at a thickness of 2.1 mm, and a broad effective bandwidth of 4.9 GHz is achieved at a thickness of only 1.6 mm. At the detection theta of 0°, the maximum radar cross-sectional (RCS) reduction value reaches 17.9 dB·m. Hence, it is expected that the leaf-like Co/C nanosheet exhibits significant advantages in the field of EM wave absorption and radar stealth, which paves the way for future exploration of high-performance EM wave absorption materials.