In-situ measurement of the heat transport in defect- engineered free-standing single-layer graphene.
In-situ measurement of the heat transport in defect- engineered free-standing single-layer graphene.
复制标题
缺陷工程独立式单层石墨烯中热传输的原位测量
DOI：
10.1038/srep21823
复制
发表时间：
2016-02-24
影响因子：
4.6
通讯作者：
Takata Y
中科院分区：
文献类型：
--
作者：
Wang H;Kurata K;Fukunaga T;Takamatsu H;Zhang X;Ikuta T;Takahashi K;Nishiyama T;Ago H;Takata Y
利用纳米加工技术，可以通过引入不同的缺陷来操纵石墨烯中的热传输。然而，由于大面积单层石墨烯（SLG）的悬浮困难和现有探测方法对温度敏感性的限制，SLG的缺陷与热导率之间的关系尚不清楚。在这项工作中，我们开发了一种新的方法来制造微型悬浮SLG。随后，使用聚焦离子束（FIB）在SLG中产生纳米孔缺陷并调节热传输。在双光束系统中，使用新型T型传感器方法现场测量了FIB辐射前后相同SLG的热导率。纳米孔缺陷使热导率降低约42%。研究发现，较小的宽度和边缘卷曲也对SLG的热导率有明显的限制。基于晶格动力学理论的计算结果，边缘粗糙度的增加和对长波长声学声子的更强散射是热导率降低的主要原因。这项工作为理解有缺陷的SLG膜中的热传输提供了可靠的数据，这可能有助于未来基于石墨烯的MEMS器件的设计。
Utilizing nanomachining technologies, it is possible to manipulate the heat transport in graphene by introducing different defects. However, due to the difficulty in suspending large-area single-layer graphene (SLG) and limited temperature sensitivity of the present probing methods, the correlation between the defects and thermal conductivity of SLG is still unclear. In this work, we developed a new method for fabricating micro-sized suspended SLG. Subsequently, a focused ion beam (FIB) was used to create nanohole defects in SLG and tune the heat transport. The thermal conductivity of the same SLG before and after FIB radiation was measured using a novel T-type sensor method on site in a dual-beam system. The nanohole defects decreased the thermal conductivity by about 42%. It was found that the smaller width and edge scrolling also had significant restriction on the thermal conductivity of SLG. Based on the calculation results through a lattice dynamics theory, the increase of edge roughness and stronger scattering on long-wavelength acoustic phonons are the main reasons for the reduction in thermal conductivity. This work provides reliable data for understanding the heat transport in a defective SLG membrane, which could help on the future design of graphene-based electrothermal devices.