title: Two-Dimensional Superlattices of Bi Nanoclusters Formed on a Au(111) Surface Using Porous Supramolecular Templates.
abstract: We used porous supramolecular structures as templates to make two-dimensional (2D) superlattices of Bi nanoclusters on a Au(111) surface. First, we applied on-surface self-assembly to prepare 2D porous supramolecular structures containing well-ordered nanopores. Then, we deposited Bi atoms on the surface. The Bi atoms were confined in the supramolecular pores and formed nanoclusters of a critical size that is defined by the pore size. These nanoclusters were arranged as a 2D superlattice dictated by the structure of the supramolecular templates. The nanocluster size and superlattice periodicity can be adjusted by appropriately designing the supramolecular structures. We further studied the formation mechanism of the nanoclusters. We found that Bi atoms could diffuse across the pore boundaries at room temperature and nucleated as clusters inside the pores. The clusters grew until they reached the critical size and became stable. We used kinetic Monte Carlo simulations to reproduce the experimental results and quantified the interpore diffusion barrier to be 0.65 eV.
authors.affiliation: Department of Physics, The Hong Kong University of Science and Technology , Clear Water Bay, Hong Kong, China.
authors.forename: Ran
authors.initials: R
authors.lastname: Zhang
authors.affiliation: Department of Physics, The Hong Kong University of Science and Technology , Clear Water Bay, Hong Kong, China.
authors.forename: Guoqing
authors.initials: G
authors.lastname: Lyu
authors.affiliation: Department of Physics, The Hong Kong University of Science and Technology , Clear Water Bay, Hong Kong, China.
authors.forename: Cheng
authors.initials: C
authors.lastname: Chen
authors.affiliation: Department of Physics, The Hong Kong University of Science and Technology , Clear Water Bay, Hong Kong, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Lin
authors.affiliation: Shanghai Key Laboratory of Functional Materials Chemistry and Institute of Fine Chemicals, East China University of Science and Technology , Meilong Road 130, Shanghai 200237, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Liu
authors.affiliation: Shanghai Key Laboratory of Functional Materials Chemistry and Institute of Fine Chemicals, East China University of Science and Technology , Meilong Road 130, Shanghai 200237, China.
authors.forename: Pei Nian
authors.initials: PN
authors.lastname: Liu
authors.affiliation: Department of Physics, The Hong Kong University of Science and Technology , Clear Water Bay, Hong Kong, China.
authors.forename: Nian
authors.initials: N
authors.lastname: Lin
keywords: Bi nanoclusters; kinetic Monte Carlo simulations; scanning tunneling microscopy; superlattice; supramolecular templates