Hui Zhao, Jin Yun, Yali Zhang, Kunpeng Ruan, Yinsen Huang, Yaping Zheng, Lixin Chen* and Junwei Gu*. Pressure-Induced Self-Interlocked Structures for Expanded Graphite Composite Papers Achieving Prominent EMI Shielding Effectiveness and Outstanding Thermal Conductivities. ACS Applied Materials & Interfaces, 2022, 10.1021/acsami.1c22950. 2020IF=9.229.（1區材料科學Top期刊）
https://pubs.acs.org/doi/abs/10.1021/acsami.1c22950
Abstract
High-performance films via layer-by-layer assembly of two-dimensional (2D) materials would provide all possibilities for the development of modern integrated electronics. However, the stacked structure between nanosheets and large-scale fabrication still remain a great challenge. Herein, the Fe3O4/expanded graphite (EG) papers are fabricated via in situ oxidation of ferrocene onto EG nanosheets, followed by a continuous roll-in process. Upon mechanical compaction, the self-interlocked structures driven by close overlapping and hooking of nanosheets in Fe3O4/EG (FG) composites remarkably facilitate the construction of phonon and electron transmission channels and improve mechanical strength. FG papers exhibit prominent shielding effectiveness (67.1 dB at ~100 μm) with enhanced absorptivity (~0.1, surpassing lots of conductive film materials), stemming from the synergistic effect of electrical and magnetic properties. Also, the electromagnetic interference (EMI) shielding performance shows prominent reliability after bending (2000 cycles) and ultrasonic treatment (30 min). The corresponding tensile strength reaches 35.8 MPa; meanwhile, the corresponding in-plane thermal conductivity coefficient is as high as 191.7 W/(m·K), which can rapidly and efficiently accelerate heat dissipation. In particular, FG papers also reveal rapid-response, controllable and highly stable Joule heating performance, and present promising prospects in the fields of radiation-proof clothing, flexible heaters, portable wearable devices, and aerospace.
二維（2D）材料逐層自組裝工藝制備的高性能薄膜將為現代集成電子產品的發展提供一切可能。然而，納米片之間的堆疊結構和大規模制造仍然是一個巨大的挑戰。因此，本文通過二茂鐵在膨脹石墨（EG）納米片上的原位氧化和連續輥壓技術制備Fe3O4/EG復合紙。在機械壓力的作用下，Fe3O4/EG（FG）復合材料中納米片間緊密重疊和相互勾連產生了自連鎖結構，不僅有利于聲子和電子傳輸通道的構建且提高了機械強度。FG復合紙表現出優異的電磁屏蔽性能（厚度100 μm時，屏蔽效能為67.1 dB），以及高的電磁波吸收率（~0.1，超過大多數導電薄膜材料）。此外，經2000次彎曲循環和30 min超聲處理后，FG復合紙的電磁屏蔽性能表現出優異的穩定性能。FG復合紙的拉伸強度達到35.8 MPa；同時，FG復合紙的面內導熱系數高達191.7 W/(m·K)，可快速高效地散熱。特別是，FG復合紙還具有快速響應、可控和高度穩定的焦耳熱性能，在防輻射服、柔性加熱器、便攜式可穿戴設備和航空航天等領域具有廣闊的應用前景。