One-dimensional magnetic Ni@C porous nanorods derived from MOF-74 for strong lightweight microwave absorption

For next-generation microwave absorption materials (MAMs), the key performance benchmarks include: (i) minimized thickness matching parameters, (ii) maximized effective absorption bandwidth, and (iii) optimized reflection loss profiles. One-dimensional (1D) magnetic Ni@C porous nanorods have been successfully fabricated through the calcination of ZnNi-MOF precursors under an argon atmosphere. The Ni@C porous nanorods exhibit exceptional electromagnetic wave (EMW) absorption performance, achieving a minimum reflection loss (RL min ) of −64.4 dB at 1.89 mm thickness and an impressive effective absorption bandwidth (EAB) of 5.7 GHz at 2.50 mm thickness at a low filler loading of only 10 wt%. Furthermore, radar cross-section (RCS) simulations indicate the Ni@C porous nanorods achieve a substantial 33.07 dB·m² CST reduction compared to the pure perfect electric conductor (PEC) plate. The outstanding EMW absorption performance originates from the unique structural design of the porous Ni@C nanorods, which simultaneously optimizes impedance matching and incorporates multiple loss mechanisms including conductive loss, dipolar polarization, magnetic resonance, and interfacial polarization effects. This robust synthetic approach presents a versatile platform for developing various 1D magnetic carbon-based composites with superior electromagnetic wave attenuation properties.