Highly Thermally Conducting Polymer-Based Films with Magnetic Field-Assisted Vertically Aligned Hexagonal Boron Nitride for Flexible Electronic Encapsulation
Highly Thermally Conducting Polymer-Based Films with Magnetic Field-Assisted Vertically Aligned Hexagonal Boron Nitride for Flexible Electronic Encapsulation
复制标题
用于柔性电子封装的具有磁场辅助垂直排列六方氮化硼的高导热聚合物基薄膜
DOI：
10.1021/acsami.9b06062
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发表时间：
2019-05-15
影响因子：
9.5
通讯作者：
Liu, Zhi-Quan
中科院分区：
文献类型：
--
作者：
Yuan, Jie;Qian, Xitang;Liu, Zhi-Quan
本文提出了一种简单、低成本、高效率的方法来构建垂直排列的六方氮化硼纳米片(HBNN)导热通道结构，以提高导热系数。首先，剥离的带负电荷的BNN和带正电的FeCo纳米立方体通过强烈的静电相互作用自组装形成复杂的纳米材料。在磁场作用下，BNN可以与FeCo纳米立方体取向，BNN的{001}面吸附在FeCo纳米立方体的{100}面上。扫描电子显微镜观察到了大范围、高密度的FeCo/hBN取向结构，这种结构可以作为热耗散通道，通过优势导热方向传输更多的声子。加入30wt%FeCo和50wt%BN的复合膜的导热系数为2.25Wm(-1)K-1，是只含有50wt%随机分布HBN的复合膜(0.325 Wm(-1)K-1)的7倍，是纯聚二甲基硅氧烷(0.114 Wm(-1)K-1)的20倍。作为发光二极管芯片的导热衬底和红外热技术，评估了复合薄膜的热管理能力。除了令人惊讶的导热系数外，FeCo-BNNS复合薄膜还表现出极好的柔韧性。
Here, a facile, low-cost, and high-efficiency method to construct a vertically aligned hexagonal boron nitride nanosheet (hBNN) thermal conduction channel structure is proposed to improve the thermal conductivity. First, exfoliated negatively charged BNNs and positively charged FeCo nanocubes self-assemble to form complex nanomaterials by strong electrostatic interactions. Then, the BNNs can orient with FeCo nanocubes in magnetic field, and the {001} facets of BNNs adsorb on the {100} facets of FeCo nanocubes. The large scale range and high-density FeCo/hBN-aligned structures are observed by scanning electron microscopy, which can act as thermal dissipation channels by conveying more phonons through a preponderant thermally conductive direction. The thermal conductivity of the composite films with 30 wt % FeCo and 50 wt % BN filler is 2.25 W m(-1) K-1, 7 times higher than that of the films only containing 50 wt % randomly distributed hBN filler (0.325 W m(-1) K-1) and 20 times higher than pure polydimethylsiloxane films (0.114 W m(-1) K-1). The thermal management capability of the composite films is evaluated as a thermal conducting substrate of a light-emitting diode chip and the infrared thermal technology. Apart from the surprising thermal conductivity, FeCo-BNNs composite films also exhibit superb flexibility.