Electrostatic-Interaction-Induced Molecular Deposition of a Hybrid Bilayer on Au(111): A Scanning Tunneling Microscopy Study

Abstract

Hybrid bilayers consisting of 8-hydroxypyrene-1,3,6-trisulfonic acid trisodium salt (HPTS) and meso-tetra(4-pyridyl)porphine (TPyP) have been successfully constructed on Au(111) and investigated by electrochemical scanning tunneling microscopy (ECSTM). Under the guidance of the electrostatic interaction between negatively charged sulfonate groups and positively charged pyridyl groups, the underlying HPTS arrays act as templates for the deposition of cationic TPyPs, forming two types of TPyP/HPTS complex bilayers. The present work provides a feasible way to fabricate hybrid multilayers on the electrode surface via electrostatic interaction, which has great significance for the design of molecular nanodevices.

Fabrication of bilayer tetrathiafulvalene integrated surface covalent organic frameworks

“…The bright dots in the second layer show larger contours than the lower ones, which has been observed in bilayer assemblies. 25 The cross-sectional profile in Fig. 2d also confirms the formation of bilayer sCOFs.…”

“…Meanwhile, the fabrication of bilayer structures in the vertical dimension (i.e., perpendicular to the basal plane of the substrate) via supramolecular self-assembly has been extensively studied for their potential use in single molecular devices. 23,24 A bilayer structure on the substrate surface can be obtained via electrostatic interaction, 25 p-p interaction, 26 as well as by assembly environment control. 27 Herein, we report the fabrication of a precise A-A stacked double layer surface COF by on-surface imine reaction between tetrathiafulvalene tetraaldehyde (4ATTF) and p-phenylenediamine (PPDA).…”

Squeezing, Then Stacking: From Breathing Pores to Three‐Dimensional Ionic Self‐Assembly under Electrochemical Control

“…Although generally highly developed,1 molecular self‐assembly at the solid–liquid interface still faces several challenges, in particular related to reaching into the third dimension. To the best of our knowledge, adaptable surface‐based supramolecular architectures perpendicular to the surface have been only achieved thus far by the use of multiple building blocks or tectons,2a–f or by charge reversal of the substrate through anion adsorption 2g. In this paper, we present a system based on an organic salt (polyaromatic cation+ perchlorate anion) whose rich supramolecular features allow us to do exactly that with a single compound and an unmodified substrate: by tuning the electrochemical potential, we can assemble the tectons into a porous structure, stretch these pores to accommodate another molecule as a guest, or stack them into an ordered bilayer in a controlled manner.…”

Electric-Field-Mediated Reversible Transformation between Supramolecular Networks and Covalent Organic Frameworks

“…For this end, the use of scanning tunneling microscopy (STM) was considered a good choice, as it combines localized control of a switchable electric field, and high-resolution imaging. The idea of applying an electric field together with STM to obtain switchable surfaces has been successfully demonstrated by taking advantage of reversible dynamic interactions, such as hydrogen bonds, , electrostatic interactions, π–π stacking, and metal–ligand interactions . In addition to these monocomponent systems, switching has also been demonstrated for bicomponent supramolecular systems and host–guest systems .…”