Polarization loss-enhanced honeycomb-like MoS2 nanoflowers/undaria pinnatifida-derived porous carbon composites with high-efficient electromagnetic wave absorption

Abstract

The increasingly serious electromagnetic pollution has caused an urgent demand for easy preparation, sustainable and low-cost electromagnetic absorbing materials with super absorption capacity. Herein, inspired by the nature, spherical MoS2 nanoflowers/undaria pinnatifida-derived honeycomb-like porous carbon composites were fabricated by a simple carbonization and subsequent hydrothermal process. The unique honeycomb-like porous microstructure of undaria pinnatifida facilitates the generation of multiple scattering and reflections and the construction of interconnected conducting networks, while the rich porous structure provides a vast surface for the growth of MoS2 crystals. In addition, MoS2 significantly not only improved the impedance matching of the composites but also greatly enhanced the polarization loss due to the simultaneous growth of MoS2 nanoflowers on the surface and in the internal pores of the undaria pinnatifida. As a result, the hybrids achieved a maximum electromagnetic wave (EMW) absorption capacity with a reflection loss (RL) value of up to −75.94 dB at a thickness of only 1.68 mm. The results indicated that the C/MoS2 hybrids can be a new prospective candidate as sustainable EMW absorbers with low density and superb EMW absorption performance.