MOF-derived jujube pit shaped C/Co composites with hierarchical structure for electromagnetic absorption

A novel flake-assembled jujube pit shaped C/Co composites assembled by plentiful flakes has been successfully synthesized by annealing Co-based metal-organic frameworks (MOFs) at different temperatures. Owing to the optimal attenuation capacity, impedance matching and unique hierarchical structure, C/Co composites annealed at 600 degrees C exhibited excellent reflection loss (RL) performance. The minimum RL value could reach -41 dB at 8.3 GHz with a matching thickness of 2.8 mm. Moreover, the effective bandwidth could reach 5.6 GHz (10.2 similar to 15.8 GHz) with a matching thickness of only 2.0 mm. This study not only provides a promising microwave absorber but also develops a facile method to synthesize C/Co composites with regular hierarchical structure. (C) 2020 Elsevier B.V. All rights reserved.