In conventional foams, electrical properties often play a secondary role. However, this scenario becomes different for 3D graphene foams (GrFs). In fact, one of the motivations for synthesizing 3D GrFs is to inherit the remarkable electrical properties of individual graphene sheets. Despite immense experimental efforts to study and improve the electrical properties of 3D GrFs, lack of theoretical studies and understanding limits further progress. The causes to this embarrassing situation are identified as the multiple freedoms introduced by graphene sheets and multiscale nature of this problem. In this article, combined with transport modeling and coarse‐grained molecular dynamic (MD) simulations, a theoretical framework is established to systematically study the electrical conducting properties of 3D GrFs with or without deformation. In particular, through large‐scale and massive calculations, a general relation between contact area and conductance for two van der Waals bonded graphene sheets is demonstrated, in terms of which the conductivity maximum phenomenon in GrFs is first theoretically proposed and its competition mechanism is explained. Moreover, the theoretical prediction is consistent with previous experimental observations.

中文翻译：

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3D石墨烯泡沫的最大电导率

在常规泡沫中，电性能通常起次要作用。但是，这种情况对于3D石墨烯泡沫（GrFs）会有所不同。实际上，合成3D GrFs的动机之一是继承单个石墨烯片材的卓越电性能。尽管为研究和改善3D GrF的电性能付出了巨大的实验努力，但缺乏理论研究和了解限制了进一步的发展。造成这种尴尬局面的原因被确定为石墨烯片材引入的多重自由度和该问题的多尺度性质。在本文中，结合输运模型和粗粒分子动力学（MD）模拟，建立了一个理论框架来系统地研究3D GrFs变形或不变形的导电特性。特别是，通过大规模和大规模的计算，证明了两个范德华键合石墨烯片的接触面积与电导率之间的一般关系，据此，首先从理论上提出了GrFs中的最大电导率现象，并解释了其竞争机理。 。此外，理论预测与先前的实验观察结果一致。