激光辐照法快速制备Co/C粒子吸波材料  

Rapid Preparation of Co/C Composite Absorber by Laser Irradiation

作　　者：王晓农 李晓霞 白秀军[1,4] 刘琦 王斌[1] Wang Xiaonong;Li Xiaoxia;Bai Xiujun;Liu Qi;Wang Bin(College of Electronic Engineering,National University of Defense Technology,Hefei 230037,Anhui,China;State Key Laboratory of Pulsed Power Laser Technology,Hefei 230037,Anhui,China;Anhui Laboratory of Advanced Laser Technology,Hefei 230037,Anhui,China;Key Laboratory of Infrared and Low Temperature Plasma of Anhui Province,Hefei 230037,Anhui,China)

机构地区：[1]国防科技大学电子对抗学院,安徽合肥230037 [2]脉冲功率激光技术国家重点实验室,安徽合肥230037 [3]先进激光技术安徽省实验室,安徽合肥230037 [4]安徽省红外与低温等离子体重点实验室,安徽合肥230037

出　　处：《光学学报》2023年第17期208-215,共8页Acta Optica Sinica

基　　金：脉冲功率激光技术国家重点实验室主任基金(2021ZR05)。

摘　　要：针对隐身和电磁防护技术对轻质、高效新型吸波材料的需求,以ZIF-67为前驱体,通过1064 nm激光辐照快速制备Co/C复合粒子。研究辐照功率对Co/C复合材料物相、微结构、电磁参数及其2~18 GHz波段吸波性能的影响。结果表明,激光辐照制备的Co纳米晶尺寸可稳定在5~20 nm,复合材料展现出丰富的Co-C界面,从而利于提升材料对电磁波的介电损耗能力。特别地,45 mW激光辐照获得的Co/C工作频段可覆盖完整的X波段(厚度为2.6 mm),最低反射损耗高达-53.9 dB,展现出优异的吸波能力。Objective Excessive electromagnetic radiation not only affects the normal operation of precision electronic equipment but also poses a potential threat to human health.Traditional microwave absorbers such as iron powder possess high magnetic permeability for effectively dissipating electromagnetic waves,but the high density restricts the applications.Although carbon materials have lower density and better conductivity,the electromagnetic wave attenuation performance needs further improvement for unfavored impedance matching.Aiming at developing the microwave absorber with light weight,high efficiency,and wide band,recently metal/carbon composites prepared by pyrolyzing metal-organic framework(MOFs)for microwave absorption have become research hotspots for their light weight and high efficiency.However,the pyrolysis process is usually performed in muffle or tube furnaces,and the slow heating rate usually leads to aggregated metal nanocrystals,thus resulting in weak interface polarization.Additionally,the preparation takes a long time(a few hours)and the pyrolysis atmosphere is usually inert gases such as argon,which makes it difficult to achieve rapid preparation.Therefore,we take laser beams as the thermal heat resource instead of traditional heat resources to achieve rapid preparation,and the micromorphology could be precisely controlled by the fast heating-quenching process,with metal nanocrystal size at nanoscale of 5-20 nm.Finally,the dielectric loss ability is enhanced with effective electromagnetic wave absorption.Methods First,we prepare the ZIF-67 precursor.0.24 g Co(NO3)2·6H2O is dissolved into 30 mL water as solution A.1.64 g 2-methylimidazole is dissolved in 30 mL water as solution B.Solution B is dropped into solution A dropwide with the reaction for 24 h.By centrifugation for three times,the purple powder ZIF-67 is obtained.Second,we prepare the Co/C composites by laser irradiation.ZIF-67 powder is uniformly spread on a platform,which could move at two dimensions(X-Y)with a moving rate of 1 cm/s.By

关 键 词：材料 激光辐照 ZIF-67 Co纳米晶 宽频 吸波 

分 类 号：O436[机械工程—光学工程]