• 文献标题:   In Situ Graphene Growth Dynamics on Polycrystalline Catalyst Foils
  • 文献类型:   Article
  • 作  者:   WEATHERUP RS, SHAHAN AJ, WANG ZJ, MINGARD K, POLLARD AJ, WILLINGER MG, SCHLOEGL R, VOORHEES PW, HOFMANN S
  • 作者关键词:   graphene, platinum, chemical vapor deposition, growth dynamic, modeling, domain shape
  • 出版物名称:   NANO LETTERS
  • ISSN:   1530-6984 EI 1530-6992
  • 通讯作者地址:   Univ Cambridge
  • 被引频次:   28
  • DOI:   10.1021/acs.nanolett.6b02459
  • 出版年:   2016

▎ 摘  要

The dynamics of graphene growth on polycrystalline Pt foils during chemical vapor deposition (CVD) arelaveitigated using in situ scanning electron microscopy and complementary structural characterization of the catalyst with electron backscatter diffraction. A general growth model outlined that considers precursor dissociation, mass transport, and attachment to the edge of a growing domain. We thereby analyze graphene growth dynamics at different length scales and reveal that the rate -limiting 'step varies throughout the process and across different regions of the catalyst surface, including different facets of an individual. graphene domain. The facets, that define the domain shapes lie normal to Slow growth directions, which are determined, by the. interfacial mobility when attachment to domain edges is rate limiting, as well as anisotropy in surface diffusion as diffusion becomes rate limiting. Our observations and analysis thus reveal that the structure of CVD graphene films is intimately linked to that of the underlying polycrystalline catalyst, with both interfacial mobility and diffusional anisotropy depending on the presence of step edges and grain boundaries. The growth model developed serves as a general framework for understanding and optimizing the growth of 2D materials on polycrystalline catalysts.