writer：Wang, RL (Wang, Ruili) [1] , [2] ; He, M (He, Man) [1] ; Zhou, YM (Zhou, Yuming) [1] ; Nie, SX (Nie,
keywords：Cubic hollow ZIF-67Self-templatedPDACo/N/C compositesMnO2 nanosheets
source：期刊
Issue time：2024年
Green and facile strategies for fabricating hollow microwave absorption materials without harmful solvent etching have attracted extensive attention but still remain a challenge. Herein, the cubic hollow Co/N/C@MnO2 composites were prepared through metal-organic frameworks (MOFs) self-templated eco-friendly method with polydopamine (PDA) as carbon source and hierarchical MnO2 nanosheets were incorporated for improving impedance mismatch caused by excessive permittivity in Co/N/C. Such a uniform distribution of Co particles in the N-doped porous carbon matrix, in association with the hollow structure and hierarchical MnO2 nanosheets, endow the composites with enhanced electromagnetic (EM) wave absorption. Notably, Co/N/C@MnO2 sample with a filler loading of 15 wt% shows extraordinary EM wave absorbing performance with the minimum reflection loss (RL) of -58.9 dB and wide absorption bandwidth of 5.5 GHz. Several minimum RL values at a thickness in the range of 1.5-5 mm, are below than -50 dB, outperforming many similar materials reported previously. Besides, the possible microwave absorption mechanism was elaborated in detail. Our work provides an environmentally friendly and facile route for fabricating MOFs self-templated hollow carbon-based microwave absorbers. (C) 2019 Elsevier Ltd. All rights reserved.