Multilayer Graphene Enables Higher Efficiency in Improving Thermal Conductivities of Graphene/Epoxy Composites

详细信息    查看全文

• 作者：Xi Shen ; Zhenyu Wang ; Ying Wu ; Xu Liu ; Yan-Bing He ; Jang-Kyo Kim
• 刊名：Nano Letters
• 出版年：2016
• 出版时间：June 8, 2016
• 年：2016
• 卷：16
• 期：6
• 页码：3585-3593
• 全文大小：552K
• 年卷期：0
• ISSN：1530-6992

文摘

The effects of number of graphene layers (n) and size of multilayer graphene sheets on thermal conductivities (TCs) of their epoxy composites are investigated. Molecular dynamics simulations show that the in-plane TCs of graphene sheets and the TCs across the graphene/epoxy interface simultaneously increase with increasing n. However, such higher TCs of multilayer graphene sheets will not translate into higher TCs of bulk composites unless they have large lateral sizes to maintain their aspect ratios comparable to the monolayer counterparts. The benefits of using large, multilayer graphene sheets are confirmed by experiments, showing that the composites made from graphite nanoplatelets (n > 10) with over 30 μm in diameter deliver a TC of ∼1.5 W m^–1 K^–1 at only 2.8 vol %, consistently higher than those containing monolayer or few-layer graphene at the same graphene loading. Our findings offer a guideline to use cost-effective multilayer graphene as conductive fillers for various thermal management applications.