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区材料科学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.

二维（2D）材料逐层自组装工艺制备的高性能薄膜将为现代集成电子产品的发展提供一切可能。然而，纳米片之间的堆叠结构和大规模制造仍然是一个巨大的挑战。因此，本文通过二茂铁在膨胀石墨（EG）纳米片上的原位氧化和连续辊压技术制备Fe3O4/EG复合纸。在机械压力的作用下，Fe3O4/EG（FG）复合材料中纳米片间紧密重叠和相互勾连产生了自连锁结构，不仅有利于声子和电子传输通道的构建且提高了机械强度。FG复合纸表现出优异的电磁屏蔽性能（厚度100 μm时，屏蔽效能为67.1 dB），以及高的电磁波吸收率（~0.1，超过大多数导电薄膜材料）。此外，经2000次弯曲循环和30 min超声处理后，FG复合纸的电磁屏蔽性能表现出优异的稳定性能。FG复合纸的拉伸强度达到35.8 MPa；同时，FG复合纸的面内导热系数高达191.7 W/(m·K)，可快速高效地散热。特别是，FG复合纸还具有快速响应、可控和高度稳定的焦耳热性能，在防辐射服、柔性加热器、便携式可穿戴设备和航空航天等领域具有广阔的应用前景。