Molecular Nanotechnology Research Section

概要

Nanotechnology is essential for highly efficient
energy use. Our group studies the basics of assembling
small molecules into the advanced materials and
devices in energy sector with high efficiency. We have
already developed several unique techniques which
are totally new molecular assembling methodology
such as ‘electro-chemical Epitaxial Polymerization’
and ‘Two-Zone Chemical Vapor Deposition (2ZCVD)’ which enable to produce molecular wires on
metal surface from small molecules. By using these
techniques, organic electronic devices such as fieldeffect transistors and organic solar cells will be
developed.
Main research achievements in Molecular
Nanotechnology Research Section in 2022 are
described below.
2. Bottom-Up On-Surface Synthesis of Edgefunctionalized Graphene Nanoribbon
Graphene nanoribbons (GNRs) have shown great
potential for electronics, optoelectronics, and
photonics. These properties strongly depend on width
and edge structure of them. Therefore, precisely
controlled width and edge structure is required for
desired properties. Bottom-up synthesis of GNRs is
one of the suitable methods to satisfy these
requirements because of the definition of their edge
structures and widths by the shape of precursors.
Atomically precise synthesis of armchair-edged GNRs
has already been achieved under ultra-high vacuum
(UHV) condition. However, given GNRs in this
method were low yield and density was still low.
Therefore, it was difficult to develop organic
electronic devices with them. To develop devices,
high-yield fabrication of assembled GNR films,
isolation, and device fabrication are required.
We have developed 2Z-CVD to produce densely
packed, parallelly aligned self-assembled GNRs on
Au(111) under low vacuum condition of 1 Torr from
halogenated polycyclic aromatic hydrocarbon (PAH)
precursors. This technique successfully produced a
series of armchair-edged GNRs in high yield. ...