At the deep end: Atomic-scale imaging of graphene in liquids

Abstract

Researchers at the Materials Integration and Nanoscale Devices group at IBM Research, Zurich, are investigating the electronic structure and dynamics of single molecules on ultra-flat metals and emerging two-dimensional nanomaterials by means of an scanning tunneling microscopy (STM) operated in a liquid environment. The STM tool is capable of operating in constant-current mode at high-speeds in both polar (requires appropriate tip insulation) and non-polar liquids with minimal thermal fluctuations. The liquid medium within the enclosed liquid-cell setup ensures stable imaging conditions and secures the tunnel gap from external contamination. Currently they are investigating graphene electrodes known to possess reduced surface mobility with respect to gold and the structure-function dependence of tailored organic molecules on graphene in collaboration with theoretical modeling groups where atomic-scale molecular dynamics simulations on these systems is performed.