Constructing multi-interface Mo2C/Co@C nanorods for a microwave response based on a double attenuation mechanism.

In this work, novel one-dimensional (1D) Mo2C/Co@C nanorods (MCRs), using a metal-organic framework (zeolitic imidazolate framework; ZIF-67) as the coating layer to form multi-interfaces, were formed via a facile hard template method. Compared with previous works relating to porous-carbon-based Mo2C nanocomposites, the well-designed MCRs in this study possess a double attenuation mechanism due to the existence of the dielectric materials Mo2C and remaining carbon (RC) and the magnetic compound Co. Thanks to a new design and the multiple useful compounds, the as-prepared MCRs have the features of demonstrating multi-interfacial polarization, a large surface area and highly isotropic dissipation. Hence, the samples not only inherit the excellent microwave absorbing abilities of Mo2C but they also have a broadened effective bandwidth. For example, the minimum reflection loss (RL) value of MCRs with 35% sample loading could reach -47.98 dB. More importantly, RL values of less than -10 dB can be observed from 11.08 to 17.08 GHz (an effective bandwidth of 6.0 GHz) with a matching thickness of 1.6 mm, which is much better than previous work involving porous-carbon-based Mo2C nanocomposites. Firstly, we have reasonably redesigned the samples to have good absorbing properties for practical applications. Secondly, we have paved a highly efficient and universal way to synthesize 1D microwave absorbers with multiple valuable interfaces.