Dual-functional graphene/carbon nanotubes thick film: Bidirectional thermal dissipation and electromagnetic shielding
Dual-functional graphene/carbon nanotubes thick film: Bidirectional thermal dissipation and electromagnetic shielding
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DOI：
10.1016/j.carbon.2020.09.017
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发表时间：
2021-01-01
期刊：
影响因子：
10.9
通讯作者：
Chen, Cheng-Meng
中科院分区：
文献类型：
--
作者：
Jia, Hui;Kong, Qing-Qiang;Chen, Cheng-Meng
航天器材料是制约航天探索领域快速发展的关键因素。在先进的航天器中，具有热管理和电磁屏蔽功能的优质多功能材料可以保证其设备在空间中的正常运行。目前，石墨烯薄膜还不能满足高热流密度和优良的通平面导热性能。本文成功制备了具有高热流密度的全碳双功能石墨烯/碳纳米管（CNTs）厚膜，并对其在2800℃热压碳化和石墨化后的结构和成分演变进行了研究，结果表明其具有致密、无缺陷、高结晶的碳结构。分子动力学模拟进一步证实了2800℃石墨化后石墨烯片与碳纳米管之间形成了C-C共价键，增强了通过面声子的传递。同时，轴向相邻的石墨烯片由CNTs连接，具有优异的导热性能。面内和透面热扩散系数分别高达1188.2 mm(2)/s和8.0 mm(2)/s。电导率高达1819.17 S/cm， EMI SE在ku波段达到75 dB。研究结果为航天器材料的制备和应用提供了广阔的前景。(C) 2020 Elsevier Ltd.版权所有。
Spacecraft materials are a key limiting factor for the rapid development of the aerospace exploration field. In an advanced spacecraft, superior multi-functional material with thermal management and electromagnetic shielding can ensure the normal operation of its equipment in space. Currently, graphene thin film can't satisfy a high heat flux and excellent through-plane thermal conduction. In this contribution, a full-carbon dual-functional graphene/carbon nanotubes (CNTs) thick film with high heat flux was successfully prepared, and the structure and composition evolution was investigated after hot-pressing carbonization and graphitization of 2800 degrees C, which indicates the existence of a compact defectsfree and high crystalline carbon structure. Molecular dynamics simulations further confirm the formation of C-C covalent bonds between graphene sheets and CNTs after 2800 degrees C graphitization, enhancing the phonons transfer in through-plane. Simultaneously, the axially adjacent graphene sheets are connected by the CNTs, which endow excellent thermal conductive properties. The in-plane and through-plane thermal diffusivity are as high as 1188.2 mm(2)/s and 8.0 mm(2)/s, respectively. Moreover, the electrical conductivity up to 1819.17 S/cm and EMI SE reach 75 dB in Ku-band. The results provide a bright prospect for spacecraft materials preparation and application. (C) 2020 Elsevier Ltd. All rights reserved.