Coronene and Phthalocyanine Trapping Efficiency of a Two-Dimensional Kagomé Host-Nanoarchitecture

Abstract

The trapping of coronene and zinc phthalocyanine (ZnPc) molecules at low concentration by a two-dimensional self-assembled nanoarchitecture of a push–pull dye is investigated using scanning tunneling microscopy (STM) at the liquid–solid interface. The push–pull molecules adopt an L-shaped conformation and self-assemble on a graphite surface into a hydrogen-bonded Kagomé network with porous hexagonal cavities. This porous host-structure is used to trap coronene and ZnPc guest molecules. STM images reveal that only 11% of the Kagomé network cavities are filled with coronene molecules. In addition, these guest molecules are not locked in the host-network and are desorbing from the surface. In contrast, STM results reveal that the occupancy of the Kagomé cavities by ZnPc evolves linearly with time until 95% are occupied and that the host structure cavities are all occupied after few hours.

Fabricating 2D Host −Guest Kagomé Packing for C2-Symmetric Aromatic Carboxylic Acids with Different Spatial Configuration: Different Ways, Same Destination

“…Controlling two-dimensional self-assembled supramolecular nanostructures on surfaces has received a great deal of attention for purely theoretical research reasons as well as applications in nanotechnology and crystal engineering. − Particularly, the well-ordered nanoporous networks, such as rhombus, Kagomé, and honeycomb, constructed by intermolecular noncovalent interactions are extensively used as host templates to immobilize and recognize functional guest molecules. − With this view, a broad range of host template structures could be obtained by adopting various geometries and functionalities of molecular building blocks. − Utilizing the so-called host–guest assembly method, the functionality and complexity of interfacial architectures can be expanded significantly. − The coadsorption of guest molecules may maximize the host–guest interactions and the van der Waals (vdW) interactions between the adsorbates and substrates to stabilize the coassembly system. − In most cases, the incorporation of guest molecules with appropriate size into the host template does not result in any movement of the host matrix. − Besides, the host molecule could adaptively reorganize 2D nanoporous networks more flexibly via the breakage and generation of noncovalent bonds induced by guest species. − Thus, it is frequently proposed that the size and shape complement of the host porous template and guest molecules play a key role in responding to guest inclusion assembly. , …”

Coronene guest molecule selectivity in host templates formed by hydrogen bonding and van der Waals forces at liquid/solid interfaces

“…21,22 Recently, a lamellar, non-porous template for the stepwise adsorption of guest species was discovered. 23 At present, there have been many studies on the adsorption kinetics of guest molecules, 24,25 the design of organic nanopore templates, 26,27 and host-guest reactions. [28][29][30] However, studies on the selective adsorption of guest molecules in different host templates are not common.…”

STM studies on porphyrins and phthalocyanines at the liquid/solid interface for molecular-scale electronics

“…[17][18][19] We argue that it is easy to transfer molecules onto a solid surface through drop casting and to control the ways in which molecules stay on the surface. [20][21][22] In addition, the presence of a solution phase facilitates the posi- tioning of molecules between the tip and the substrate for molecular junctions. Molecular level studies on porphyrins and phthalocyanines will be discussed in terms of conductance, rectification, magnetism and switching, with the prospects for application of these metal complexes in single-molecule electronics.…”