• 文献标题:   Nanoparticle shape selection by repulsive interactions: Metal islands on few-layer graphene
  • 文献类型:   Article
  • 作  者:   SOMERS LA, ZIMBOVSKAYA NA, JOHNSON AT, MELE EJ
  • 作者关键词:  
  • 出版物名称:   PHYSICAL REVIEW B
  • ISSN:   1098-0121
  • 通讯作者地址:   Univ Penn
  • 被引频次:   2
  • DOI:   10.1103/PhysRevB.82.115430
  • 出版年:   2010

▎ 摘  要

Metal atoms adsorbed on few-layer graphenes condense to form nanometer-size droplets whose growth is size limited by a competition between the surface tension and repulsive electrostatic interactions from charge transfer between the metal droplet and the graphene. For situations where the work-function mismatch is large and the droplet surface tension is small, a growing droplet can be unstable to a family of shape instabilities. We observe this phenomenon for Yb deposited and annealed on few-layer graphenes and develop a theoretical model to describe it by studying the renormalization of the line tension of a two-dimensional droplet by repulsive interparticle interactions. Our model describes the onset of shape instabilities for nanoparticles where the growth is size limited by a generic repulsive potential and provides a good account of the experimentally observed structures for Yb on graphene.