摘要
Renewable porous biochar and 2 D MXene have attracted significant attention in high-end electromagnetic interference(EMI)shielding fields,due to unique orderly structures and excellent electrical conductivity(r)value.In this work,the wood-derived porous carbon(WPC)skeleton from natural wood was performed as a template.And excellent conductive and ultra-light 3D MXene aerogel was then constructed to prepare the MXene aerogel/WPC composites,based on highly ordered honeycomb cells inner WPC as a microreactor.Higher carbonization temperature is more conducive to the graphitization degree of natural wood.MXene aerogel/WPC composites achieve the optimal EMI SE value of up to 71.3 d B at density as low as 0.197 g/cm^3.Such wall-like"mortar-brick"structures(WPC skeleton as"mortar"and MXene aerogel as"brick")not only effectively solve the unstable structure problem of MXene aerogel networks,but also greatly prolong the transmission paths of the electromagnetic waves and dissipate the incident electromagnetic waves in the form of heat and electric energy,thereby exhibiting the superior EMI shielding performance.In addition,MXene aerogel/WPC composites also exhibit good anisotropic compressive strength,excellent thermal insulation and flame retardant properties.Such ultra-light,green and efficient multi-functional bio-carbon-based composites have great application potential in the high-end EMI shielding fields of aerospace and national defence industry,etc.
研究制备轻质、绝热和阻燃于一体的电磁干扰(EMI)屏蔽材料来抵抗日益严重的辐射污染是一个巨大的挑战.可再生多孔生物碳和2D过渡金属碳化物(MXene)由于独特的结构和出色的电导率备受EMI屏蔽研究者的关注.本研究以天然木头高温碳化生成的木基多孔碳(WC)骨架为模板,基于WC内部高度有序的蜂窝微孔为微反应器,将高导电和轻质的3D MXene气凝胶构筑其中,制备MXene气凝胶/WC复合材料.研究表明,较高的碳化温度更利于天然木头的石墨化程度.制备的MXene气凝胶/WC复合材料在低至0.197g/cm^3的密度下实现了高达71.3 d B的优异EMI屏蔽效能.这种类似于墙的"泥-砖"结构(WC骨架充当"泥",MXene气凝胶充当"砖"),不仅有效解决了MXene气凝胶网络结构不稳健的问题,还可以大大延长电磁波的传输路径,从而表现出优异的EMI屏蔽性能.此外,更具有实际应用意义的是,这种兼具优异EMI屏蔽、绝热和阻燃性能的轻质材料在航空、航天等国防军事工业和建筑工程等领域有着巨大的应用潜能.
基金
supported by the Foundation of National Natural Science Foundation of China(51973173)
Natural Science Basic Research Plan for Distinguished Young Scholars in Shaanxi Province of China(2019JC-11)
Space Supporting Fund from China Aerospace Science and Industry Corporation(2019-HT-XG)
Foundation of Aeronautics Science Fund(2017ZF53071)
the School-enterprise Collaborative Innovation Fund for Graduate Students of Northwestern Polytechnical University(XQ201913)。
作者简介
Corresponding author:顾军渭,is a full Professor and Leader of the Structure/Function Polymer Composites Group at the School of Chemistry and Chemical Engineering,NPU.He received his Ph.D.degree of Materials Science from NPU in 2010.His current research focuses on the thermally conductive polymer composites,fibres/polymeric matrix wavetransparent composite materials as well as electromagnetic shielding polymer composites.E-mail addresses:gjw@nwpu.edu.cn,nwpugjw@163.com;梁超博, obtained a Bachelor’s degree from Northwestern Polytechnical University(NPU)in 2015.Currently,he is a doctoral student majoring in Materials Science at NPU.His research interests focus on the microstructure design,performance control and mechanisms investigation of the electromagnetic shielding polymer composites.
