Ping Song, Zhonglei Ma*, Hua Qiu, Yifan Ru and Junwei Gu*. High-Efficiency Electromagnetic Interference Shielding of rGO@FeNi/Epoxy Composites with Regular Honeycomb Structures. Nano-Micro Letters, 2022, 14: 51. 2020IF=16.419.（1區材料科學Top期刊，2021中國最具國際影響力學術期刊）
https://doi.org/10.1007/s40820-022-00798-5
Abstract
With the rapid development of fifth-generation (5G) mobile communication technology and wearable electronic devices, electromagnetic interference (EMI) and radiation pollution caused by electromagnetic waves have attracted worldwide attention. Therefore, the design and development of highly efficient EMI shielding materials are of great importance. In this work, the three-dimensional (3D) graphene oxide (GO) with regular honeycomb structure (GH) is firstly constructed by sacrificial template and freeze-drying methods. Then the amino functionalized FeNi alloy particles (f-FeNi) are loaded on the GH skeleton followed by in-situ reduction to prepare rGH@FeNi aerogel. Finally, the rGH@FeNi/epoxy EMI shielding composites with regular honeycomb structure is obtained by vacuum-assisted impregnation of epoxy resin. Benefitting from the construction of regular honeycomb structure and electromagnetic synergistic effect, the rGH@FeNi/epoxy composites with a low rGH@FeNi mass fraction of 2.1 wt% (rGH and f-FeNi are 1.2 wt% and 0.9 wt% respectively) exhibit a high EMI shielding effectiveness (EMI SE) of 46 dB, which is 5.8 times of that (8 dB) for rGO/FeNi/epoxy composites with the same rGO/FeNi mass fraction. At the same time, the rGH@FeNi/epoxy composites also possess excellent thermal stability (heat-resistance index and temperature at the maximum decomposition rate are 179.1oC and 389.0oC respectively) and mechanical properties (storage modulus is 8296.2 MPa).
隨著現代5G通信技術和可穿戴電子設備的快速發展，由電磁波引起的電磁干擾和對人體的電磁輻射問題引起了社會各界的廣泛關注，高效電磁屏蔽材料的設計研發顯得尤為重要。本文首先通過犧牲模板-冷凍干燥法構建規整蜂窩結構石墨烯（rGH）骨架，再將表面功能化改性的磁性FeNi合金顆粒（f-FeNi）負載于rGH骨架制備rGH@FeNi氣凝膠，真空輔助浸漬環氧樹脂后經高溫固化得到具有規整蜂窩結構的rGH@FeNi/環氧樹脂電磁屏蔽復合材料。得益于規整蜂窩結構和電磁復合體系的構建，當rGH@FeNi質量分數僅為2.1 wt%時（rGH為1.2 wt%，f-FeNi為0.9 wt%），rGH@FeNi/環氧樹脂復合材料的電磁屏蔽效能（EMI SE）值提升至46 dB，是同等rGO/FeNi質量分數下共混rGO/FeNi/環氧樹脂復合材料EMI SE（8 dB）的5.8倍。同時，rGH@FeNi/環氧樹脂復合材料還具有優異的熱穩定性（耐熱指數和發生最大分解速率的溫度分別為179.1oC和389.0oC）和力學性能（儲能模量為8296.2 MPa）。
論文亮點
1. 通過“犧牲模板-冷凍干燥-真空輔助浸漬”法制備了具有規整三維蜂窩結構的rGH@FeNi/環氧樹脂電磁屏蔽復合材料。
2. 三維蜂窩結構的構建和電磁協同效應可以顯著提高復合材料的電磁屏蔽性能，同時賦予復合材料優異的熱穩定性和力學性能。