Nanomaterials Chemistry Workshop 2024

April 4-5, 2024
@Joint Research Laboratory Building
Uji Campus, Kyoto University

Sponsored byInternaJonal Joint Usage/Research Center (iJURC),
InsJtute for Chemical Research, Kyoto University

ScienJﬁc Program
April 4 (Thursday)
13:20-13:30

Welcome Remarks & Introduc9on of iJURC
Toshiharu TERANISHI (Kyoto Univ.)
Chair: Tatsuya TSUKUDA

13:30-14:00“Surface Engineering of Metallic Nanocrystals via Atomic Structure andComposi9on Control for Boos9ng Electrocatalysis”
Sang Woo HAN (KAIST)

14:00-14:30“Pla9num Group Metal-Based Solid-Solu9on Alloy Nanocrystals: Binary toHigh-Entropy Alloys”
Hiroshi KITAGAWA (Kyoto Univ.)

14:30-15:00“Designed Synthesis and Assembly of Inorganic Nanomaterials for Energy
and Cataly9c Applica9ons”
Taeghwan HYEON (Seoul Na9onal Univ.)

15:00-15:30“Transforma9on and Advanced Proper9es of Isolated and Assembled Ionic
Nanocrystals”
Toshiharu TERANISHI (Kyoto Univ.)

15:30-15:45

Break
Chair: Jinwoo CHEON

15:45-16:15“Nanoclusters and Quantum Dots”
Sungjee KIM (POSTECH)

16:15-16:45“Stability-Func9on Rela9onship in Molecular Electronics”
Hyo Jae YOON (Korea Univ.)

16:45-17:15“Metal-Organic Frameworks for Advanced Polymers”
Takashi UEMURA (Univ. Tokyo)

17:15-17:30

Discussion

Today’s all speakers

April 5 (Friday)
Chair: Toshiharu TERANISHI
09:30-10:00“Porous Ionic Crystals Based on Metal-Oxo Clusters as a Placorm for
Func9onal Materials”
Sayaka UCHIDA (Univ. Tokyo)

10:00-10:30“Chemical Nanoplasmonics: From Nanopar9cle Synthesis to SurfaceEnhanced Spectroscopic and Biodiagnos9c Applica9ons”
Jwa-Min NAM (Seoul Na9onal Univ.)

10:30-11:00“STM Studies of Plasmon-induced Chemical Reac9ons at a Single-molecule
Level”
Emiko KAZUMA (Univ. Tokyo)

11:00-11:15

Break
Chair: Jwa-Min NAM

11:15-11:45“Designer Nanomachines for Biological Systems”
Jinwoo CHEON (Yonsei Univ.)

11:45-12:15“Single-Atom Signaling and Metalloallostery: Bioinorganic Chemistry
Beyond Ac9ve Sites”
Christopher J. CHANG (Univ. California, Berkeley)

12:15-12:45“Atomically Precise Gold Clusters as Model Catalysts”
Tatsuya TSUKUDA (Univ. Tokyo)

12:45-13:00

Discussion

13:00-13:05

Concluding Remarks

Today’s all speakers

Tatsuya TSUKUDA (Univ. Tokyo)

Access & Venue• From the Airport to Kyoto StaJon
see hgps://www.kuicr.kyoto-u.ac.jp/sites/icr/about/access/to_kyoto_sta9on/• From Kyoto StaJon to Venue (Uji Campus)
JR Kyoto to Obaku sta9on: ~20 min(every 15 min; placorms 8-10; take a local train, NOT a rapid train)
JR Obaku sta9on to venue: ~5 min walk

Abstract
Surface Engineering of Metallic Nanocrystals via Atomic
Structure and ComposiJon Control for BoosJng Electrocatalysis
Sang Woo HAN (Korea Advanced Ins9tute of Science and Technology)
Since the clean energy industry emerged, developing eﬃcient nanocrystal catalysts has
agracted ever-increasing agen9on. Recently, the u9liza9on of metal nanocrystals as catalysts
for electrochemical reac9ons is entering a new era with the development of theories andtechniques that help incorporate surface chemistry into nanoscale materials. Current
approaches in the ﬁeld of nanocrystal catalysts include detailed analyses and modiﬁca9onsof the surface atoms of nanocrystals, with which op9mal structures and composi9ons fortarget electrochemical reac9ons could be realized. In this presenta9on, I introduce recently
developed strategies to engineer the surface structure of nanocrystals through control over
the atomic arrangement and composi9on of nanocrystal surfaces for boos9ng
electrocatalysis.

PlaJnum Group Metal-Based Solid-SoluJon Alloy Nanocrystals:
Binary to High-Entropy Alloys
Hiroshi KITAGAWA (Kyoto University)
Pla9num group metal (PGM) nanopar9cles (NPs) have been inves9gated in a variety of
research ﬁelds such as catalysis and electronics. Among the types of alloys, solid-solu9on
alloy NPs have the advantage of being capable of con9nuously changing their proper9es bytuning their composi9on. However, synthesizing PGM solid-solu9on alloy NPs with any
combina9on and composi9on is not an easy task due to the metallurgical aspects. In thiswork, we have focused on PGM-based solid-solu9on alloy NPs, and in par9cular those withimmiscible alloy systems.
The physical and chemical proper9es of most solids are strongly correlated to their electronic
structure, in par9cular the DOS at the EF. In 2015, we proposed the “DOS engineering”
concept for designing materials, which calls for the control not only of the loca9on of the dband center, but also of a suitable DOS shape, such as the band width and the DOS shape ofunoccupied and occupied stated around EF. We propose that by means of “interelement
fusion,” where the elemental periodic table is colored by the s, p, d, and f groups, it ispossible to manipulate the shape of the DOS freely by choosing elements from the s, p, d,and f groups according to the proper9es desired.

Designed Synthesis and Assembly of Inorganic Nanomaterials
for Energy and CatalyJc ApplicaJons
Taeghwan HYEON (Seoul Na9onal University)
Recently we have focused on the architecture engineering of inorganic nanomaterials fortheir applica9ons to electrocatalysis and photocatalysis. We present a synthesis of highly
durable and ac9ve fuel cell electrocatalysts based on ordered M-Pt alloy nanopar9cles foroxygen reduc9on reac9on (ORR) in PEMFC. We synthesized highly ac9ve and stableelectrocatalysts for hydrogen peroxide (H2O2) produc9on including Co-N4(O) moiety
incorporated in nitrogen-doped graphene (Co1-NG(O)) and cobalt phthalocyanine (CoPc)
immobilized on oxidized carbon nanotube substrate. The electrocataly9c oxygen evolu9on
reac9on (OER) plays a pivotal role in the mass produc9on of hydrogen fuel and chemical
feedstocks by various electrochemical reac9ons. We report that early transi9on metals withvacant d orbitals (d0-oxoanions) directly par9cipate in and accelerate the alkaline OER via aredox cycle associated with early transi9on metal–peroxo species. We demonstrate that
ac9ve machine-learning on even small datasets can discover a “champion” four-metal
perovskite oxide OER catalyst. We report on the design and synthesis of highly ac9ve TiO2
photocatalysts incorporated with site-speciﬁc single copper atoms that exhibit highphotocataly9c hydrogen genera9on and CO2 photoreduc9on ac9vity. We presented aﬂoatable photocataly9c placorm constructed from elastomer-hydrogel nanocomposites,
demonstra9ng its superiority over conven9onal systems in solar hydrogen produc9on. We
demonstrated a general method for synthesizing atomically dispersed catalysts via
photochemical defect tuning for controlling oxygen vacancy dynamics.

TransformaJon and Advanced ProperJes of
Isolated and Assembled Ionic Nanocrystals
Toshiharu TERANISHI (Kyoto University)
Elaborate chemical synthesis methods allow the produc9on of various types of inorganic
nanocrystals (NCs) with uniform shape and size distribu9ons. Then, how can we synthesize
NCs with thermodynamically metastable phases or very complex structures? The
transforma9on of already-synthesized NCs via elemental subs9tu9ons, such as ion exchange
reac9ons for ionic NCs and galvanic replacement reac9ons for metal NCs, can overcome thediﬃcul9es facing conven9onal one-step syntheses. In par9cular, NC ion exchange reac9ons
have been studied with numerous combina9ons of foreign ions and ionic NCs with various
shapes. The func9onality of the resul9ng ionic NCs, including semiconduc9ng and plasmonic
proper9es, can be easily tuned in a wide range, from the visible to near-infrared. Here wefocus on the full ion exchange reac9ons involving ionic NCs and NC superlatces, highligh9ng
important aspects such as the preserva9on of appearance and dimensions. Finally, we show
the advanced op9cal proper9es of ca9on-exchanged NCs and concerted op9cal proper9es ofNC superlatces.

Nanoclusters and Quantum Dots
Sungjee Kim (POSTECH)
Magic sized clusters (MSCs) are thermodynamically stable intermediate nanoclusters ouen
captured during the growth of semiconductor nanopar9cles (NPs). MSCs can be isolated asintermediates in quantum dot (QD) synthesis, and they provide pivotal clues inunderstanding QD growth mechanisms. We report syntheses for two families ofheterogeneous-atom-incorporated InP MSCs that have halide or zinc atoms. All the MSCs
could be directly synthesized from conven9onal molecular precursors. Alterna9vely, eachseries of MSCs could be prepared by sequen9al conversions. As the conversion proceeded,
evolu9on from uni-molecule-like to QD-like characters was observed. Early stage MSCs
showed ac9ve inter-state conversions in the excited states, which is characteris9cs of small
molecules. Later stage MSCs exhibited narrow photoinduced absorp9ons at lower-energy
region like QDs. The crystal structure also gradually evolved from polytwistane to more zincblende. We also introduced halide atoms (Cl, Br, I) as dopants into MSCs. Chirop9cal ac9vi9esof III-V group QD growth intermediates, or MSCs, will be addressed as sugges9ng chiral MSCs
as prospec9ve materials on designing chirop9cal nanomaterials. InP nanopar9cles andnanostructures synthesized from InP MSCs will be also discussed.

Stability-FuncJon RelaJonship in Molecular Electronics
Hyo Jae YOON (Korea University)
In the ﬁeld of molecular electronics, the stability of the ac9ve component, speciﬁcally, selfassembled monolayer (SAM), exerts a signiﬁcant inﬂuence over the func9onality of thecorresponding molecular tunnel junc9on. The number and types of molecular orbitals thatenter external bias windows dictate the shape of the current-voltage curve and themagnitude of current ﬂowing through the junc9on. Moreover, in thermoelectric molecular
junc9ons, the asymmetry in the hole-electron density of states (DOS) is inﬂuenced by theamount of heat applied to the junc9on. Consequently, the inherent instability of
conven9onal SAMs poses a formidable obstacle to fully understanding the mechanisms
underlying charge transport through organic magers and hinders the development of novel
func9onali9es. Addressing this challenge, our research group has recently devised strategies
grounded in supramolecular and organometallic approaches to bolster the electrical andthermal stability of SAMs on noble-metal surfaces. The remarkable improvements in stability
have enabled us to explore charge tunneling across unprecedentedly wide bias windows anddelve into the atomic-level intricacies of the Seebeck eﬀect at substan9ally elevatedtemperature ranges. These signiﬁcant ﬁndings will be described in detail in this presenta9on.

Metal-Organic Frameworks for Advanced Polymers
Takashi UEMURA (The University of Tokyo)
Metal-Organic Frameworks (MOFs) composed of metal ions and organic ligands have been
extensively studied. The characteris9c features of MOFs are highly regular channel structureswith controllable pore sizes approxima9ng molecular dimensions and designable surface
func9onality. Thus, MOFs have been successfully applied in numerous domains, including
storage and separa9on, catalysis, energy, and sensing. However, the majority of rela9ve
studies in the early stages of MOF research focused on gas and solvent molecules as guests,
despite the poten9al of inﬁnite nanochannel structures for the encapsula9on ofmacromolecules.
Since 2005, we have u9lized the regular and tunable channels of MOFs for a ﬁeld ofpolymeriza9on, which can allow mul9-level controls of polymers, nanopar9cles, andnanographenes. In addi9on, construc9on of nanocomposites between MOFs and polymers
provides unprecedented material placorms to accomplish many nanoscale func9on. We
have also developed direct inser9on of polymers into nanochannels of MOFs, which enables
powerful macromolecular recogni9on and separa9on technologies with excep9onally highselec9vity. Designing nano-sized pores of MOFs with a regular arrangement of reac9ve/
interac9ve/responsive en99es oﬀers the possibility of universal polymer produc9on andpuriﬁca9on that cannot be accomplished by conven9onal methods.

Porous Ionic Crystals Based on Metal-Oxo Clusters
as a Pla`orm for FuncJonal Materials
Sayaka UCHIDA (The University of Tokyo)
Porous crystalline materials such as zeolites and metal-organic frameworks (MOFs) haveagracted wide agen9on due to their well-deﬁned porous structures and high surface area,
which are useful in gas storage and separa9on, ion exchange and conduc9on, andheterogeneous catalysis. Polyoxometalates (POMs) are nano-sized anionic metal-oxo clusters
with unique cataly9c, electrochemical, magne9c, and luminescent proper9es. We havereported that the complexa9on of POMs with molecular ca9ons with appropriate elements,
charges, sizes, symmetry, ligands, etc., results in the forma9on of voids and channels in the
crystal latce. The proper9es of porous ionic crystals (PICs) based on POMs can besummarized as follows. (a) POMs show reversible redox proper9es, which can lead to theforma9on of “redox-ac9ve” PICs. (b) Guest binding and cataly9cally ac9ve sites can beincorporated beforehand into the ionic components. These func9ons can be maintained andu9lized in the PICs since the ionic components remain as discrete molecules in the crystal
latce. (c) POMs can transport protons as counter ca9ons eﬃciently because the nega9ve
charge of POMs is smeared over the external oxygen atoms, reducing the eﬀec9ve surface
charge density. These proper9es lead to interes9ng func9ons in selec9ve ion-uptake/exchange, proton conduc9on, heterogeneous catalysis, forma9on of luminescent mixedvalence metal clusters, etc., which are unique to PICs.

Chemical Nanoplasmonics: From NanoparJcle Synthesis to
Surface-Enhanced Spectroscopic and BiodiagnosJc ApplicaJons
Jwa-Min NAM (Seoul Na9onal University)
Plasmonics deals with understanding and manipula9ng the interac9on between light andmager at a scale that is signiﬁcantly smaller than the wavelength of light (e.g., metal
nanopar9cles), and chemical nanoplasmonics is mainly about the study and use of nanoscalechemistry for advancing plasmonics and the use of plasmonics to address key issues andchallenges in chemistry and other related ﬁelds. Designing, synthesizing and controlling
metal nanostructures with a superhigh precision for a large number of structures are thekeys to the reliable and widespread use of plasmonic nanostructures in chemistry, materials
science, op9cs, nanoscience, biotechnology and medicine. Here, I will share the design,synthe9c strategies and characteriza9on results of molecularly tunable and structurally
reproducible plasmonic nanostructures including metal nanogap structures, mul9component metal nanopar9cles and gold nanocatenanes with strong, controllable andquan9ﬁable plasmonic signals (e.g., quan9ta9ve surface-enhanced Raman scagering). I willthen show their poten9al in addressing some of important challenges in plasmonics,
biosensing, bioimaging and therapeu9cs, and discuss how these new plasmonic materials
and placorms can lead us to new breakthroughs in nanochemistry, next-genera9on diseasediagnos9cs, molecular compu9ng and nanomachines/nanorobo9cs.

STM Studies of Plasmon-induced Chemical ReacJons
at a Single-molecule Level
Emiko KAZUMA (The University of Tokyo)
Localized surface plasmons of metal nanostructures enable the eﬃcient use of solar light andhave been used for various applica9ons such as local spectroscopies, sensing, photovoltaics,
ﬂuorescence enhancement, and photocatalysts. Among the various applica9ons, plasmoninduced chemical reac9ons are agrac9ng increasing researchers’ agen9on as novel
photocataly9c reac9ons. During the excita9on and decay processes of the plasmons, strong
electric ﬁelds, hot carriers, and heat are generated and can serve as excita9on sources forthe molecules, and thus several reac9on mechanisms have been proposed. However, thereac9on mechanism remains to be fully elucidated due to the diﬃculty of direct observa9onof the chemical reac9ons in the plasmonic ﬁeld strongly localized near the metal surface. A
scanning tunneling microscope (STM) combined with op9cal excita9on by light can be used
to inves9gate plasmon-induced chemical reac9ons on metal surfaces. This techniqueprovides insights into the mechanism and pathways of the plasmon-induced chemical
reac9ons at a single-molecule level, which cannot be obtained by conven9onal macroscopic
methods. Our single-molecule studies reveal that the degree of the orbital hybridiza9on at
the metal−molecule interface aﬀects the molecular excita9on by the plasmons anddetermines the dominant excita9on mechanism.

Designer Nanomachines for Biological Systems
Jinwoo CHEON (Yonsei University)
One of the important trends of next-genera9on biomedical sciences is the development of
new tools that can accurately image, iden9fy, and execute desired missions in a selec9vely
programmed manner for biological systems. In this talk, I will discuss the design ofnanomachines as placorm tools for a variety of func9onali9es such as sensing targe9ng andsignaling of cells and live animals in a selec9ve and eﬃcient way. These tools serve not only
as a contrast agent for highly accurate MR imaging but also a modulator for cell signaling of
neurons via magneto-gene9cs for the behavior control of live animals. This is a new approachof controlling neurons via magne9sm which will serve for deep brain s9mula9ons via remote
and wireless neuromodula9ons.
[References]
1. Lin, M., Lungerich, D., Cheon, J. et al. “A magne9cally powered nanomachine with a DNA
clutch” Nat. Nanotechnol., 2024. online published.
2. Kim, W.-S., Shapiro, M. G., Cheon, J. et al. “Magneto-acous9c protein nanostructures for
non-invasive imaging of 9ssue mechanics in vivo” Nat. Mater., 2024, 23, 290.
3. Lee, J.; Cheon, J. et al. “Non-contact long-range magne9c s9mula9on of mechanosensi9ve
ion channels in freely moving animals” Nat. Mater., 2021, 20, 1029.
4. Shin, T.; Choi, B.; Cheon, J. et al. “High-resolu9on T1 MRI via renally clearable dextran
nanopar9cles with an iron oxide shell” Nat. Biomed. Eng., 2021, 5, 252.

Single-Atom Signaling and Metalloallostery:
Bioinorganic Chemistry Beyond AcJve Sites
Christopher J. CHANG (University of California, Berkeley)
Metals in biology play essen9al roles in health and disease as they span a unique con9nuum
from metabolism to signaling. Mo9vated to study metals in their na9ve biological contexts
and how they are misregulated in disease, we are developing molecular imaging probes totrack dynamic metal pools with spa9al and temporal resolu9on and proteomics probes tocharacterize metal-dependent targets of cell signaling. This presenta9on will focus on ourlatest work in the development of metal-responsive sensors and their applica9on to decipher
single-atom transi9on metal signaling pathways and metalloallostery in fundamental
behaviors such as ea9ng and sleeping.

Atomically Precise Gold Clusters as Model Catalysts
Tatsuya TSUKUDA (The University of Tokyo)
Gold clusters protected by organic ligands, stabilized by polymer, and immobilized by solid
supports have provided ideal placorms to study the correla9on between various structure
parameters and cataly9c proper9es. This talk will introduce precision synthesis and structuralcharacteriza9on of Au clusters and discuss how the cataly9c performances are aﬀected by
key structural parameters such as size, doping, and surface modiﬁca9on. These fundamental
studies will establish a guiding principle to design and op9mize the cataly9c proper9es of Aubased clusters. The topic includes the following recent examples:(1) Photocatalysis by phosphine-protected MAu12 (M = Au, Pd, Rh, Ir, Pt) [1, 2].
(2) Electrocatalysis by N-heterocyclic carbene-protected Au11 [3] and Au24 [4].
(3) Alcohol oxida9on by poly(N-vinyl-2-pyrrolidone)-stabilized Au24 [5], Au38 [6] and Au23Pd1[7].
(4) Alcohol oxida9on by Au25 supported on double metal hydroxide [8], par9ally thiolated
Au25 anchored on carbon [9], and par9ally thiolated Aun (n = 25, 102) on layered doublehydroxide [10].
[References][1] ChemElectroChem. 11, e202300669 (2024). [2] Angew. Chem., Int. Ed. 61, e202207290(2022). [3] Nature Chem. 11, 419–425 (2019). [4] J. Am. Chem. Soc. 144, 9000–9006 (2022).
[5] JACS Au 1, 660–668 (2021). [6] ACS Catal. 12, 6550–6558 (2022). [7] ACS Nano 16, 16932–
16940 (2022). [8] Nanoscale 14, 3031–3039 (2022). [9] ACS Catal. 13, 3263–3271 (2023). [10]ACS Catal. 13, 16179–16187 (2023).