Spreading and orientation of silver nano-drop over a flat graphene substrate: An atomistic investigation

The spreading and orientation of silver nano-drop over the graphene substrate are important in various
applications such as flexible electronic, bio-medical, electrochemical, and coating materials, etc and have
been explored by molecular dynamics simulations. The tuning of interaction energy parameter between
graphene and silver affects both spreading and phase transitions of silver nano-drop over the graphene
substrate. At high interaction energy, silver nano-drops spread over the graphene substrate and solidified
at a higher temperature compared to lower interaction energies. Silver depicts fcc with a layered hcp
structure over the graphene substrate during cooling from 1500 K to 10 K. However, at the interface
between graphene and silver nano-drop, silver shows the fcc{111} planner orientations. Spreading and
orientation of silver nano-drop over the graphene substrate has been characterized by estimation of
interaction energies, average number distributions, bond order parameters, the percentage of a crystalline atom during solidification. The results suggest that the silver nano-drop depicts the unique crystal
structure with high thermal stability over the graphene substrate compared to the bulk. Therefore, it is
extremely desirable material for the development of an efficient catalyst and flexible electronic circuits.