Facile Synthesis of Nitrogen-Doped Porous Ni@C Nanocomposites with Excellent Synergistically Enhanced Microwave Absorption and Thermal Conductive Performances

Abstract

Herein, multifunctional nitrogen-doped porous Ni@C (Ni@NPC) microwave absorbers with excellent synergistically enhanced microwave absorption and thermal management capabilities were successfully fabricated by a facile “Liquid-Solid-Solid” method. The as-synthesized Ni@NPC nanocomposites exhibited tunable excellent microwave absorption performance with a maximum effective absorption band (EAB) of 7.8 GHz with a thickness of 1.9 mm, and a minimum reflection loss (RL) of -54.8 dB at 13.12 GHz. The outstanding microwave absorbing performance should be attributed to the special 3D nitrogen-doped porous Ni@C hybrid hierarchical architecture, which can promote the formation of three-dimensional transmission network and provide multiple pathways of electromagnetic loss including dipolar polarization, interfacial polarization, magnetic loss and conduction loss to synergistically enhance microwave absorption performances of the absorbers. Thermal conductive experiment indicated that the as-synthesized Ni@NPC absorbers could significantly improve the thermal conductivity of the reference sample and exhibited excellent thermal management capacities. Thus, this work provides an idea for low-cost development of high-performance multifunctional absorbing materials.

Keywords: nitrogen-doped porous carbon, Ni nanoparticles, Microwave absorption, heat conduction