Nanopatterning of Donor/Acceptor Hybrid Supramolecular Architectures on Highly Oriented Pyrolytic Graphite: A Scanning Tunneling Microscopy Study

Abstract

Hybrid supramolecular architectures have been fabricated with acceptor 1,4-bis(4-pyridylethynyl)-2,3-bis-dodecyloxy-benzene (PBP) and donor 2,6-bis(3,4,5-tris-dodecyloxyphenyl)dithieno[3,2-b:2′,3′-d]thiophene (DTT) compounds on highly oriented pyrolytic graphite (HOPG) surfaces and their structures and molecular conductance are characterized by scanning tunneling microscopy/spectroscopy (STM/STS). Stable, one-component adlayers of PBP and DTT are also investigated. The coadsorption of two-component mixtures of PBP and DTT results in a variety of hybrid nanopattern architectures that differ from those of their respective one-component surface assemblies. Adjusting the acceptor/donor molar ratio in mixed adlayer assemblies results in dramatic changes in the structure of the hybrid nanopatterns. STS measurements indicate that the HOMO and LUMO energy levels of PBP and DTT on an HOPG surface are relatively insensitive to changes in the hybrid supramolecular architectures. These results provide important insight into the design and fabrication of two-dimensional hybrid supramolecular architectures.

Structure and structural transition of chiral domains in oligo(p-phenylenevinylene) assembly investigated by scanning tunneling microscopy

“…These diversiform chiral organizations can be unified into one chiral structure after thermal annealing. An effective way is proposed to change the chiral structure by cocrystallization of OPV3-CHO with other molecules like that used in molecular engineering, surface science, and supramolecular chemistry (19)(20)(21)). Here we demonstrate that with coadsorption of OPV3-CHO with alkyl bromides, diversiform chiral structures can be unified into one chirality.…”

Molecular insights into photostability of fluorinated organic photovoltaic blends: role of fullerene electron affinity and donor–acceptor miscibility

“…Scanning tunneling spectroscopy (STS) coupled with scanning tunneling microscopy (STM) is a powerful technique for probing nanoscale morphology in semiconductor materials. [57][58][59][60] Indeed, the STS/STM technique has been employed to determine the band edges of nanostructures, 59 to map the band structure in a pn-junction with nanometer resolution, 61 to investigate cross-sectional interfaces in model BHJ OPV systems, 62 and was recently used by us to probe the inuence of additives on polymer and fullerene domain size in an OPV active layer. 16 With this technique, transient conductance (dI/ dV) images can be used to differentiate semiconductor components based upon their electronic levels and localized density of states (DOS), i.e., polymer and fullerene HOMO and LUMO levels.…”

Thermodynamic Controlled Hierarchical Assembly of Ternary Supramolecular Networks at the Liquid–Solid Interface

“…The structural difference between the three components results in different molecule/substrate interactions and therefore preferential adsorption is expected when these molecules are brought into contact with the substrate 9d. 25 Thus after reaching equilibrium the molar ratio in solution is not neccesarily the same as on the surface, and may also be different from the original solution conditions due to adsorption of the molecules 26…”