A Grant-in-Aid for Scientific Research on Innovative Areas
The Area Number 2509 (2013-2018)

MOLECULAR ARCHITECTONICS
Orchestration of Single Molecules for Novel Functions
News Letter No.10

A01 Prof. Hidemitsu Uno

November 2016

Ring-expanded porphyrins without
meso-bridges

A03 Prof. Yoshihiro Asai
Thermoelectric effect and its dependence onmolecular length and sequence in single
DNA molecules

We have successfully synthesized cyclo[10]pyrrole

Studying the thermoelectric effect in DNA is

1 and POM-to-Rings 2. The absorption spectrum ofimportant

1 exhibited a markedly red-shifted, intensified L

mechanisms

band at 1982 nm. X-ray crystallographic analysis

applications of DNA molecules. Here we report arevealed the structure of 1 as the isolated largest

study of the thermoelectric effect in single DNA

cyclo[n]pyrrolethe and the sandwich structure of 2,molecules. By varying the molecular length and

the POM anion held between two cyclo[8]pyrroles

sequence, we tune the charge transport in DNA towith weak hydrogen-bonding interaction with theeither

POM to the pyrrolic NH groups. The CV of 2regimes. The thermoelectric effect is small andshowedofinsensitive to the molecular length in the hopping

cyclo[8]pyrrole and no wave of the POM anion inregime. In contrast, the thermoelectric effect is

contrast with the double-decker complex oflarge and sensitive to the length in the tunnelling

porphyrin directly coordinated with POM. The

regime. These findings indicate that one may

further investigations for the NDR measurement ofcontrol the thermo- electric effect in DNA by

POM-to-Rings 2 are under way with Ogawa group.

varying its sequence and length. We describe the(T. Okujima et al., JACS 2016, 138, 7540; TL 2016, 57,

experimental results in terms of hopping and3160.).

tunnelling charge transport models. (Y. Li et al.,positively

shiftedredox

waves

aforunravelling

andhopping-fororchargetransport

developing

relevant

tunnelling-

Nature Communication. 2016, 7, 11294).

dominated

~Molecular
A01
Optical effect ofmetal-coordination to an
insulated molecular wire

A02
Novel molecule sensor byusing atomic layeredmaterial technology

Mr. Takuro Hosomi(Kyoto University)

Mr. Nguyen Tat Trung(Tohoku University)!-conjugated polymers are promising materials

Molecule detection in a variety of environments

for use in molecular devices due to their superior

is indispensable technology for understand theoptical or electrical properties. However, theirlife phenomena and development of science

physicalbesociety. Electronic device is one of application

dramatically decreased in the condensed phases,

resolve the matter of previous molecule detection

due!-!

technique such as chemical reaction, fluorescenceinteractions. To suppress the interpolymer !-!

marker and radiation marker. In recent year, asinteractions,the material of electronic device, atomic layered

properties

to

their

werestrongwepolyrotaxane-type

known

to

interpolymer

previously
insulateddeveloped

molecularwires

material is paid attention.

(IMWs), which have macrocycles that cover

Atomic layered material like MoS2, WSe2 has!-conjugatedmainintermolecularinteractions.

tosuppress

two-dimensional

Theyexhibitedadvantage of two-dimensional structure is that itproperties,

suchashighitself is ultrathin film less than 1 nm. In otheremissionefficiency

andwords, the surface states much effect on solid

efficient wiring to nanoelectrodes. We recentlystates, for the surface area is very big against its

focuses on the effect of metal-coordination to thevolumes.

IMWs. For this purpose, a platform-type IMWIn this study, we try to read out the peculiar

which

the

information of molecule from electronic device

backbone was synthesized (figure). This structure

adsorbed bio-molecules by only using current. To

allows metal ions to access the coordination sites,

realize brain mapping by development of novel

simultaneously preventing interactions between

high accuracy molecule sensor is our priority.

superior

physicalconductivity,

has

highchainsmetal-coordination

sites

onthe wires by insulation. Metal coordination to thepolymer caused various change of their emission
color, enabling easy and reversible tuning of theluminescent color. The tuned results and efficientemission were maintained even in the solid-state
due

tostructures,

theirthree-dimensional

which

demonstrated

molecular properties of the material.

insulation
superiorstructure.

ThebiggestArchitects~

Electrical

A03

A04

Resistive Switching Effects inLarge-Area MolecularJunctions with Metal
Complex Molecular Wires

Rational Concept for Reducing
Growth Temperature in
Vapor-Liquid-Solid Process ofMetal Oxide Nanowires

Ms. Mariko Yamaguchi(Osaka University)

Mr. Zetao Zhu(Kyushu University)

switchingaVapor-liquid-solid (VLS) growth process of single

high-conductance state is one of the basic

crystalline metal oxide nanowires has proved theelements for application of data storage, logic

excellent ability to tailor the nanostructures.

operations or electric circuits to signal processing.

However, the VLS process of metal oxides in

It has been reported that the electrical properties

generaloftemperatures,

molecularfromjunctions

ausinglow-toredox-activerequires

relatively

whichhighessentially

growthlimits

themolecules show resistive switching. For practicalapplication range. Here we propose a rational

applications

aconcept to reduce the growth temperature in VLS

two-terminal crossbar structure is considered togrowth process of various metal oxide nanowires.

be suitable.

Molecular dynamics simulations theoreticallyofsuch

kindofjunctions,

We made large-area molecular junctions[1]predict that it is possible to reduce the growthwith metal complex molecular wires synthesizedtemperature in VLS process of metal oxide

in a stepwise manner on the Au bottom

nanowires by precisely controlling the vapor flux.

electrode[2]. First, a 40 nm thick Au electrode wasThis concept is based on the temperature

prepared. Bis(terpyridine)iron complex wires

dependent

were then coordinated in the holes of 10 µm in

appropriate vapor flux for VLS process ofdiameter. Finally, conductive poly(3,4-ethylene-nanowire growth decreases with decreasing thedioxythio-phene)-poly(styrenesulfonate) (PEDOT:

growth temperature. Experimentally, we foundPSS, 100 nm) was spin-coated in order to avoid

the applicability of this concept for reducing thethe penetration of metal atoms during thegrowth temperature of VLS processes for various

deposition of the top Au electrode (100 nm).

metal oxides including MgO, SnO2 and ZnO. In

Devicescurrent-voltage

addition, we show the successful applications ofcharacteristics as shown in the figure. Moreover,this concept to VLS nanowire growths of metal

nonvolatileoxides onto tin-doped indium oxide (ITO) glass

showedhysteretic

resistiveswitching

performancesmaterial

window

were observed with applying pulse voltage. Byandimpedance measurement, it is suggested that

relatively low growth temperatures.

these resistive switching effects mainly occur atthe molecular wire/conductive polymer interface.

[1] H.B. Akkerman et al., Nature 441, 69 (2006).
[2] Y. Nishimori et al., Chem. Asian. J. 4, 1361 (2009).

polyimide

fluxsubstrates,

which

that

therequire7th Area Meeting
19 October, 2016
Chikushi Hall, Fukuoka

The

Molecular

The 5th Workshop for Young Researchers,

Architectonics was held on October 19, 2016 at

attended by approximately 30 students from

Chikushi Hall, Kyushu University, Fukuoka.

our area, was held on the same day as the Area

There were more than 50 attendees includingMeeting.

allthe7thArea

group

Meeting

leaders,of5th Workshop for Young Researchers
19 October, 2016
Chikushi Campus, Fukuoka

groupmembers,students and collaborators.

We had a very long poster session, from 5p.m. to 10 p.m., with sandwiches and snacks.

In this meeting, all presentators reported

Every attendee voted for the best poster at thetheir collaborations. 53 intra-area and 105

end of the poster session. The best poster award

inter-area collaborations have been promoted

winners are listed below:

since the start of our project. It is important tohave suggestions from the members of ourMr. Yoichi Sasaki (Kyushu Univ.)area, particularly to early stage collaborations.

Mr. Takashi Tamaki (Osaka Univ.)

Finally we are grateful that Prof. Fukuyama

Ms. Chie Nakamura (Kyushu Univ.)

and Prof. Matsushige, the academic evaluators,

Mr. Zetao Zhu (Kyushu Univ.)

and Prof. Tanaka, the academic investigator,
also attended the meeting and provided

We also discussed the plan for the next

invaluable advice.

workshop for young researchers.

Edited by “Molecular Architectonics” Chief Office
1-3 Machikaneyama, Toyonaka, Osaka 560-8531
Mail: office@molarch.jp