MoO3-MoC/Co@NC coupled heterostructures with strong connections and abundant interfaces for electromagnetic wave absorption

Abstract

Improving the electromagnetic wave (EMW) absorption capability at the thin thickness of heterostructures is critical but remains a great challenge. Here, we propose a MoO3 @ZIF-67 core-shell heterostructure derived molybdenum trioxide- molybdenum carbide/cobalt@N-doped carbon (MoO3-MoC/Co@NC) coupled heterostructure with a one-dimensional (1D) short rod-like structure for EMW absorption. A strong connection is constructed between Co@NC nanoparticles (NPs) and MoO3-MoC specie due to the pyrolysis strategy and in situ reaction between MoO3 nanobelts and ZIF-67 rhombic dodecahedrons. The abundant heterointerfaces between N-doped carbon (NC) and metallic Co, Co@NC NPs and MoC species, Co@NC NPs and MoO3 nanobelts, as well as MoC and MoO3 nanobelts improve the interfacial polarization. Abundant defects, such as N heteroatoms and oxygen vacancies, are also established in the MoO3-MoC/Co@NC coupled heterostructure. As a result, the MoO3-MoC/Co@NC coupled heterostructure inherits excellent EMW absorption performance with a reflection loss (RL) value of − 64.3 dB at a thickness of 3.875 mm, outperforming many advanced EMW absorbers. This work shows the great potential of strong connections and abundant interfaces in heterostructure for improvements of EMW absorbers.