Nanoscale stripe arrays templated on Moire patterns in graphite

SURFACE SCIENCE

卷:646

Article

McNally, Michael J.¹  Koc, Mumin Mehmet¹  Torricelli, Gauthier¹  von Haeften, Klaus¹ 

[1] Univ Leicester, Dept Phys & Astron, Univ Rd, Leicester LE1 7RH, Leics, England

关键词: Nanoparticles;    HOPG;    Graphene;    Self assembled monolayers;    Moire;   

DOI  :  10.1016/j.susc.2015.09.006

来源: Elsevier

【 摘 要 】

Large areas of nanoscale stripe arrays were produced by drop casting silica nanoparticle solutions on highly oriented pyrolytic graphite surfaces at room temperature and imaged with atomic force microscopy. The alignment of the striped areas always reflected the threefold symmetry of the graphite surface. Two different patterns were observed, with different coverages, line separations and mutual orientation, being offset by 30 degrees. Measurement of the relative angles and separations of the line patterns showed a very good match with an underlying Moire pattern, resulting from the rotation of the top graphene layers. Closer-spaced lines were attributed to the zig-zag direction of the Moire pattern whereas wider-spaced lines belonged to the armchair direction. The different abundance and apparent difference in long-term stability suggested that stability was governed by the number of reactive vertices per unit area as opposed to the number of vertices per line-length. Whilst sequential images recorded over several days revealed long term stability of all zig-zag arrays, attachment and detachment of single nanoparticles was observed. By contrast, arrays aligned in the armchair direction appeared and vanished collectively, suggesting condensation and evaporation of a fluid of nanoparticles floating on the surface. (C) 2015 Elsevier B.V. All rights reserved.

【 授权许可】

Free