在多晶石墨烯中跨越谷物界限定制电力运输
Adam W Tsen1, Lola Brown, Mark P Levendorf
1Department of Applied Physics, Cornell University, Ithaca, NY 14853, USA.
Science (New York, N.Y.)
|June 2, 2012
概括
在化学蒸汽沉积 (CVD) 石墨烯中的粒度边界 (GBs) 在连接良好时惊人地提高了电导率. 这表明高质量的多晶石墨烯可以与单晶性能相匹配.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 纳米技术 纳米技术
背景情况:
- 通过化学蒸汽沉积 (CVD) 合成的多晶石墨烯含有颗粒边界 (GB),可以阻碍电荷载体的移动性.
- 由于间接测量方法,以前的研究缺乏GB结构和电气特性之间的直接相关性.
研究的目的:
- 直接调查CVD石墨烯中的单个GBs的电性.
- 为了将GBs的原子结构和位置与其测量的电导率相关联.
- 评估聚晶石墨烯在高性能电子应用中的潜力.
主要方法:
- 传输电子显微镜 (TEM) 用于在CVD石墨烯中高分辨率成像GBs.
- 在现场测量各个GB的电力传输.
- TEM结构数据与电导度测量的相关性.
主要成果:
- 首次实现了对个别GBs的直接电气测量.
- 意想不到的是,对于具有优越域间连接性的 GBs,电导率提高了数量级.
- 证明了优化的生长和设备设计可以产生多晶石墨烯,其性能与剥皮石墨烯相比.
结论:
- CVD石墨烯的电性能高度依赖于GBs的质量.
- 连接良好的GB不一定会降低,甚至可以增强电气性能.
- 具有优化的GBs的多晶石墨烯为实现高性能电子设备提供了可行的途径.
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