Hollow MoC/NC Sphere for Electromagnetic Wave Attenuation: Direct Observation of Interfacial Polarization on Nanoscale Hetero-interfaces

Carbon-based composites with hetero-interfaces is a group of promising electromagnetic wave absorbing materials (EWAMs) for its excellent dielectric loss. For developing this kind of EWAM, in situ constructing hetero-interfaces and revealing its attenuation mechanism are of great importance, but remain challenges. Herein, a MoC incorporated N-doped carbon hollow sphere (H-MoC/NC) with uniformly distributed nanoscale MoC/NC hetero-interfaces is precisely synthesized for evaluating interfacial polarization in electromagnetic wave attenuation. The Mo defects in MoC not only contributed to the impedance matching through the hollow shell, but also accelerate the charge transfers displaying an enhanced interfacial charge polarization. More importantly, this polarized charge distribution on MoC(-)/Carbon(+) interface was first observed directly through the hologram at nanometer scale. The atomic-level understanding of interfacial polarization in electromagnetic attenuation process will greatly promote the development of designing and synthesizing non-magnetic carbon-based EWAMs.