High-performance microwave absorption enabled by Co₃O₄ modified VB-group laminated VS₂ with frequency modulation from S-band to Ku-band

High performance microwave absorption (MA) materials especially those with tunable frequency are highly desirable for telecommunication industries and military camouflage in the information era. Herein, we constructed hierarchical heterostructures based on VB-group laminated vanadium disulfide (VS₂) nanosheets embedded with cobalt tetroxide (Co₃O₄) nanoparticles. The highly dispersed Co₃O₄ nanoparticles generate strong electromagnetic coupling networks that could enhance the loss properties of MA materials. Moreover, the interconnected VS₂ layered network results in dipolar/interfacial polarization, multiple reflection and scattering favorable for the enhanced MA performance. Impressively, the maximum reflection loss of the VS₂/Co₃O₄ hybrids containing 10% Co₃O₄ can reach 57.96 dB at a thin thickness of 1.57 mm, and the bandwidth with an RL value less than -10 dB is as large as 3.5 GHz. The effective MA band could be adjusted in a range of 15.1 GHz (2.9-18 GHz) from S to Ku bands by the increase in thickness from 1.2 mm to 5.5 mm. The results show that the synergistic effect of multiple loss mechanisms and good impedance matching could be the reasons for strong MA capability in nearly all frequency bands, and thus, the high-performance and lightweight MA materials could be developed by the VS₂/Co₃O₄ hybrids.