summary of professional accomplishmentsichf.edu.pl/r_act/hab/sashuk_autoreferat_en.pdfthe synthesis...

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Institute of Physical Chemistry PAS

SUMMARY OF PROFESSIONAL ACCOMPLISHMENTS

The synthesis of nanoparticles and their organization at fluid interfaces

Volodymyr Sashuk

Attachment No. 3 to the habilitation application

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Contents

1. Personal data........................................................................................................................................ 3

2. Description of scientific achievement underlying the habilitation application ................................... 3

2.1 Title of the scientific achievement ................................................................................................ 3

2.2 List of publications supporting the scientific achievement ........................................................... 3

2.3. Discussion of the scientific achievement ..................................................................................... 5

3. List of other publications ................................................................................................................... 17

3.1 Papers published before the doctoral degree ............................................................................... 17

3.2 Papers published after the doctoral degree .................................................................................. 18

4. Patents and patent applications .......................................................................................................... 20

5. Conference presentations .................................................................................................................. 21

6. Invited talks ....................................................................................................................................... 22

7. Research projects ............................................................................................................................... 22

8. Evaluation activity ............................................................................................................................. 23

9. Science popularization ...................................................................................................................... 23

10. Teaching activity ............................................................................................................................. 23

11. Prizes and awards ............................................................................................................................ 24

12. Summary of all scientific achievements .......................................................................................... 24

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1. Personal data.

Dr. Volodymyr Sashuk

Head of the group "Chemistry in Confined Spaces" at the Institute of Physical Chemistry PAS

Education

Master of Chemistry: Lviv National University, Lviv 2002

Doctor of Chemistry: Institute of Organic Chemistry PAS, Warsaw 2007

Experience

2002-2007 doctoral student

Institute of Organic Chemistry, Polish Academy of Sciences, in the group of Prof. K. Grela

2004 intern

Max Planck Institute for Coal Research, Mülheim an der Ruhr (Germany), in the group of Prof. A.

Fürstner

2007 assistant

Institute of Organic Chemistry, Polish Academy of Sciences, in the group of Prof. K. Grela

2008-2009 post-doc

Darmstadt Technical University, Darmstadt (Germany), in the group of Prof. H. Plenio

2010-present adiunct

Institute of Physical Chemistry, Polish Academy of Sciences, in the group of Prof. Marcin Fiałkowski

(2010-2015)

2. Description of scientific achievement underlying the habilitation application

2.1 Title of the scientific achievement

The synthesis of nanoparticles and their organization at fluid interfaces

2.2 List of publications supporting the scientific achievement

Article 1. Sashuk, V.; Rogaczewski, K. A halogen-free synthesis of gold nanoparticles using gold(III)

oxide. J. Nanopart. Res. 2016, 18, 261. IF: 2,101.

I am the author of the idea and the research concept. I developed the method for the synthesis

of gold nanoparticles from gold(III) oxide in the presence of aliphatic amines; I examined the

reaction mechanism and kinetics; I compiled the results, prepared the graphical material for

publication, wrote the manuscript, corresponded with the editor during the submission of the

manuscript and prepared responses to the reviewers.

I estimate my contribution as 80%.

Article 2. Sashuk, V.; Hołyst, R.; Wojciechowski, T.; Fiałkowski, M. Close-packed monolayers of

charged Janus-type nanoparticles at the air-water interface. J. Colloid Interface Sci. 2012,

375, 180-186. IF: 3,782.

I am a co-author of the idea and research concept. I developed the method for modifying the

surface of nanoparticles with a mixed layer of ligands; I developed the conditions of

preparation of monolayers of these nanoparticles at the air-water interface using the

Langmuir-Blodgett technique; I measured contact angles, electric charge and pressure-area

isotherms of the nanoparticle monolayers; I compiled the results, prepared the graphical

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material for publication, wrote the manuscript, prepared responses to the reviewers and

prepared the text of the patent application.


Article 3. Sashuk, V.; Hołyst, R.; Wojciechowski, T.; Górecka, E.; Fiałkowski, M. Autonomous self-

assembly of ionic nanoparticles into hexagonally close-packed lattices at a planar oil-water

interface. Chem. Eur. J. 2012, 18, 2235-2238. IF: 5,771.

I am a co-author of the idea and research concept. I developed the conditions for the self-

assembly of the nanoparticles into a hexagonally packed monolayer at an oil-water interface;

I performed the measurements of contact angle and electric charge of the monolayer; I

compiled the results, prepared the graphical material for publication, wrote the manuscript,

and prepared responses to the reviewers.


Article 4. Sashuk, V.; Winkler, K.; Żywociński, A.; Wojciechowski, T.; Górecka, E.; Fiałkowski, M.

Nanoparticles in a capillary trap: dynamic self-assembly at fluid interfaces, ACS

Nano 2013, 7, 8833-8839. IF: 13,334.

I am the author of the idea and research concept. I developed the first prototype of

dynamically self-assembling system at the air-water interface and participated in further

development of this prototype; I was involved in the preparation of the graphical material for


manuscript, prepared responses to the reviewers, and prepared the text of patent application.


Article 5.Sashuk, V. Thiolate-protected nanoparticles via organic xanthates: mechanism and

implications. ACS Nano 2012, 6, 10855-10861. IF: 13,334.

I am the author of the idea and research concept. I developed the method for coating

nanoparticles with thiol ligands using organic xanthates; I examined the reaction mechanism

and kinetics; I compiled the results, prepared the graphical material for publication, wrote

the manuscript, corresponded with the editor during the submission of the manuscript,

prepared responses to the reviewers, and prepared the text of the patent application.


Article 6. Sobczak, G.; Wojciechowski, T.; Sashuk, V. Submicron colloidosomes of tunable size and

wall thickness. Langmuir 2017, 10.1021/acs.langmuir.6b04159. IF: 3,993.

I am the author of the idea and research concept. I developed the first system undergoing

self-assembly at the interface of oil-in-water emulsion droplets and participated in further

development of this prototype; I was involved in the preparation of the graphical material for


manuscript, and prepared responses to the reviewers.


Number of publications: 6

Sum of IF1: 42.315

Number of citations2: 48

1 Acc. to Journal Citation Reports on 01.02.2017

2 Acc. to Web of Science on 01.02.2017

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2.3. Discussion of the scientific achievement

The idea of manipulating matter down to the level of individual atoms, known now

as nanotechnology, although circulated in the minds of philosophers and scientists for a long time, was

probably publicly announced for the first time in 1959 by Richard Feynman, Nobel laureate in

physics.1 The famous speech entitled "There's Plenty of Room at the Bottom" comprised fantastic

visions of constructing miniature machines and data media invisible to the human eye. The idea was to

use atoms or groups of atoms as building blocks just like a Lego game. Since then, many of

Feynman’s dreams have become reality. We are witnessing a progressive miniaturization as

exemplified by computers. We can literally watch single atoms and chemical reactions. However, we

still do not have the technical capacity to precisely align atoms, or their conglomerates of nanometric

dimensions, the so-called nanoparticles. It should be noted that nanoparticles, composed of hundreds

or even tens of thousands of atoms, often show properties quite different from macroscopic matter due

to quantum effects and have been the object of great interest to scientists for over two decades now. As

in the case of atoms, utilization of the properties of single nanoparticles is not straightforward, and in

the most cases is unnecessary. It is much simpler to use the cumulative effect from a group of

nanoparticles, especially if they are ordered. For instance, in analytical applications, this facilitates the

registration and quantification of the signal, which in this case is characterized by a greater intensity

and homogeneity, and hence repeatability. The ordering often leads to changes in the intrinsic

properties of the nanoparticles, bringing new interesting physical and chemical phenomena. The

ordering is also important in giving the shape to

nanoconstructions and ensuring their

robustness. As already mentioned, the

production of ordered structures from

nanoparticles seems presently practically

unfeasible. The only manner in which this has

been accomplished is to use self-assembly,

which is a spontaneous process driven by non-

covalent interactions.2 Although we are able to

predict and then design some of the interactions

by modifying the physicochemical properties of

nanoparticles, the process of self-assembly is still difficult to control. Structures formed from

nanoparticles are usually heterogeneous, with different shapes and sizes, especially when the process

is carried out in bulk phase (Figure 1a). In order to direct self-assembly, the so-called scaffolds are

used.3 Liquid interfaces are some of the simplest naturally occurring scaffolds. The fluid interface

ensures high mobility of nanoparticles allowing to repair the errors that arise during self-assembly and

to obtain highly ordered structures (Figure 1b). When the self-assembly takes place at planar

interfaces, nanoparticles organize into two-dimensional structures, i.e. monolayers. At curved

interfaces, nanoparticle monolayers wrapped around the emulsion droplets give three-dimensional

structures, i.e. capsules.

Self-assembly of nanoparticles at fluid interfaces has been extensively studied over the past

decade.4-7

One of the first approaches employed to arrange nanoparticles into two-dimensional

structures was the Langmuir-Blodgett technique. The nanoparticle monolayers were fabricated by

compression of nanoparticles with two movable barriers at the air-water interface. Thus prepared

monolayers, however, usually contain many defects and voids. This happens due to aggregation of

nanoparticles which must be quite hydrophobic to stay on the water surface. (Figure 2a).8 Much better

results were obtained by evaporating the solvent from nanoparticle dispersions. Typically, the

evaporation of the solvent affords concentric patterns, the so-called "coffee rings".9 However, in the

Figure 1. Illustration of self-assembly of nanoparticles in bulk phase (a) and at phase interfaces (b).

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presence of a surfactant, when the evaporation is slow, hexagonally packed monolayers can be

produced.10-12

During the evaporation, the nanoparticles move from the bulk to the interface by

convection flows until a dense monolayer is formed (Figure 2b). After the solvent is evaporated, the

nanoparticle layer is deposited on the newly created interface. Nanoparticles can be also brought to the

liquid interface by changing the chemical composition of biphasic systems (Figure 2c).13-16

The

addition of alcohol (e.g. ethanol) to the aqueous dispersion of negatively charged nanoparticles causes

them to segregate at the interface.17

It was initially thought that the nanoparticles become less polar

and move to the interface due to charge dilution on their surface through adsorption of alcohol

molecules. Recent studies indicate that ethanol molecules dilute

the negative charge, most likely at the liquid

interface.18

Consequently, the absorptive barrier, resulting from

electrostatic repulsions between nanoparticles and the interface,

vanishes. After the segregation at the interface, the nanoparticles,

however, rarely form ordered structures. As in the previous

methods, the ordering is achieved only after removal of the

solvent or the addition of a surfactant.19-21

The literature data indicate that the long-range ordering

of nanoparticles on planar interfaces still remains a

challenge. This is mainly due to strong attractive and repulsive

interactions between nanoparticles. In order to mitigate these

interactions chemical additives are used. This, however, is not

always sufficient. In most cases, the ordering is only attained

after complete removal of one of the liquid phases. This is a

multi-step process which necessitates considerable interference in

the colloidal system.

The problem of long-range ordering is also observed at

curved interfaces. The resulting three-dimensional structures, i.e.

capsules, usually consist of sparse or aggregated nanoparticle

layers.22-29

Another problem is the stability of the capsules, especially those smaller than one

micron. The latter show high potential for applications in medicine30

and catalysis.31

The small size

allows the microcapsules to penetrate freely through tissues and increases their active surface. On the

other hand, a thin wall, made of a single nanoparticle monolayer, enables quick exchange of chemical

or biological species between the capsule interior and the surrounding environment. As in the case of

two-dimensional structures, stable submicron capsules are formed in the presence of auxiliary

chemicals or even other nanoparticles. In the few works reported so far,32-37

the stabilization of

microcapsules was achieved through multiple electrostatic interactions between various components of

the colloidal system. Although the developed methods are effective, the complexity of such systems

limits their applicability.

In my work, which is a part of this application, I focused on solving the major issues of self-

assembly of nanoparticles at liquid interfaces. The first problem concerns the long-range arrangement

both at planar and curved interfaces. The second issue is the stability of submicron capsules formed at

curved interfaces. First, I sought model colloidal systems in which to study self-assembly. This led to

the development of a new method for the synthesis of gold nanoparticles from gold(III) oxide (article

1). Then, I developed a method for covering the surface of gold nanoparticles with a mixture of

hydrophobic and hydrophilic ligands. The latter were imparted with an electric charge to balance the

forces acting on the nanoparticles at interfaces. This allowed to uniformly disperse the nanoparticles at

the air-water interface and to obtain a dense monolayer using the Langmuir-Blodgett

technique (article 2). Then, I found that thus modified nanoparticles spontaneously self-assemble into

Figure 2. Fabrication of nanoparticle films at interfaces: a) Mechanical compression of nanoparticles; b) Evaporation of the solvent; c) Changing the chemical composition of the bulk phase.

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hexagonally packed monolayers at an oil-water interface without any outside interference (article

3). Then I discovered that these nanoparticles also self-assemble at liquid interfaces if the system is

out of thermodynamic equilibrium (article 4). In the following studies, I worked on the stabilization of

nanoparticle structures formed at the interfaces. This resulted in the development of a method for

modifying the surface of nanoparticles with cross-linking ligands (article 5). This method enabled the

preparation of amphiphilic nanoparticles capable of self-assembling and cross-linking into ordered

three-dimensional structures, i.e. capsules, at curved interfaces in emulsions (article 6).

I would like to note that the publication order of the results does not necessarily reflect the

chronology of their accomplishment. Priority was given to the results with a greater chance of

response from the scientific community.

We used gold nanoparticles as a model system for studying self-assembly because of their

high chemical inertness and ease of functionalization with thiol ligands. Furthermore, their optical and

catalytic properties may be useful in different applications. In our study, we needed gold nanoparticles

of different size ranges with a high degree of monodispersity. Unfortunately, nanoparticles coated with

organic ligands larger than 10 nm had poor colloidal stability. On the other hand, nanoparticles smaller

than 4 nm were difficult to visualize by scanning electron microscopy (SEM). Also, the energy of

adsorption of such nanoparticles at liquid interfaces is comparable with thermal energy kTb. At that

time, a few methods for the preparation of monodisperse nanoparticles were known. The majority of

the methods were not suitable for our purposes. We found that the modification of the nanoparticles

with thiol ligands is effective if the particle surface is pre-coated by weakly binding ligands, e.g.

amines. A popular method developed by Brust38

was ineffective due to the presence of strongly

adsorbed thiol ligands. The nanoparticles obtained using the Turkevich method39

aggregated during

extraction from aqueous solutions to the organic phase. Finally, we employed the Peng method.40

This

method provides concentrated solutions of amine-coated gold nanoparticles with core diameter of

about 4-7 nm. Importantly, the amine ligands can

easily be replaced by thiol ligands. Nonetheless,

throughout the duration of the project, we attempted to

synthesize larger nanoparticles in the 8-10 nm range.

This would allow us to investigate the influence of

nanoparticle size on the self-assembly at fluid

interfaces.

The result of these attempts was the

development of a new method for the synthesis of gold

nanoparticles by reduction of gold(III) oxide with

oleylamine (article 1, Figure 3a). In this method, the

amine acts also as a solvent and a ligand. We obtained

nanoparticles with diameter of about 9 nm and

polydispersity of 26%. The nanoparticles are prepared

by agitating gold(III) oxide in oleylamine at high

temperatures (above 130°C) for several hours. Under

prolonged heating the nanoparticles become more

monodisperse due to ripening. The reaction was

monitored in situ following the change of plasmon

resonance in UV-Vis spectra (Figure 3b). The

nanoparticle size and shape were determined by SEM

(see Figure 3c). The chemical composition of the

nanoparticles was analyzed by X-ray photoelectron spectroscopy (XPS). It was found that the core of

the nanoparticles consists of metallic gold and their surface is covered with neutral amine ligands

Figure 3. The synthesis of gold nanoparticles from gold(III) oxide (Article 1): a) Reaction scheme; b) Reaction kinetics (UV-Vis); c) SEM image of the nanoparticles and their size distribution; d) Gold and nitrogen XPS spectra of the nanoparticles.

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(Figure 3d). The lack of oxidized gold species indicated the completion of the reaction. We also

studied the mechanism of the reduction of gold(III) to gold(0) in the presence of oleylamine. Energy

dispersive X-ray spectroscopy (EDX) confirmed that gold(III) oxide is reduced by oleylamine. IR,

NMR and MS analyses revealed the chemical transformations of the amine during the nanoparticle

synthesis. For instance, we detected a nitrile compound, which is the primary product of amine

oxidation. Under the reaction conditions the compound undergoes subsequent reactions to give amide

and amidine derivatives. Unfortunately, attempts to use these nanoparticles in the studies on the

interfacial self-assembly failed due to high polydispersity. Nonetheless, we demonstrated the utility of

the developed methodology for the synthesis of

gold-silver nanoparticles. Normally, the methods

based on metal halides afford non-stoichiometric

bimetallic nanoparticles due to precipitation of a

silver halide.41

The absence of halides in our

approach enables the efficient mixing of the

metal precursors, and consequently, the

preparation of alloyed nanoparticles.

In the following studies, we used gold

nanoparticles obtained by the Peng method. As

already mentioned, the poor ordering of

nanoparticles after self-assembly is mainly due

to strong repulsive or attractive interactions

between particles at liquid interfaces. We

decided to counterbalance these interactions by

modifying the nanoparticle surface with two

types of ligands with different properties (article

2, Figure 4a). We chose commercially available

1-undecanethiol (UDT) containing a

hydrophobic aliphatic chain, and a thiol

compound terminated with hydrophilic

trimethylammonium group (TMA). The latter

was synthesized in three steps using literature

procedures. UDT is responsible for attractive

interactions, whereas TMA, due to the presence

of positive electric charge, causes electrostatic

repulsion. The nanoparticles were modified

using a prescribed amount of the ligands. The

reaction was monitored by NMR. To this end,

the ligands were desorbed from the nanoparticle

surface with iodine. NMR analysis showed that

the ligand ratio was the same as in the feed

mixture. Next, we examined the influence of

TMA content on the interfacial behavior of the

nanoparticles. The nanoparticles with TMA

content of more than 10% migrated from the interface into the aqueous phase. If the TMA content was

less than 10%, the nanoparticles remained at the interface. In further research, we employed

nanoparticles containing 10% of TMA. We found that such nanoparticles are dispersed uniformly at

the interface due to lateral electrostatic stabilization. In order to obtain dense monolayers, we used the

Langmuir-Blodgett technique. Pressure-area isotherms showed that the nanoparticle monolayers,

Figure 4. Self-assembly of nanoparticles at the air-water interface (Article 2): a) Experimental set-up; b) Compression-decompression isotherm of the nanoparticles on the water surface; c) Photograph of the compressed nanoparticle monolayer; d) Wettability and structure of the nanoparticle monolayer deposited on solid support; e) FTIR spectra of the nanoparticles collected from the solution and interface; f) SEM image of the compressed nanoparticle monolayer deposited on silicon.

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owing to electric charge, are very stable and collapse at high surface tensions (Figure 4b). The

observed hysteresis is likely due to partial diffusion of nanoparticles to the aqueous phase during the

compression. This method enables the production

of large area monolayers (Figure 4c). Then, the

monolayers can be deposited on virtually any

surface (e.g. glass, ITO, silicon) using an

automatic dipper. The structure of the monolayer

deposited on silicon was revealed by SEM

(Figure 4f). The dense arrangement was obtained

at the pressure corresponding to the cusp of the

isotherm. Further experiments showed that both

sides of the monolayer are not equivalent. The

side exposed towards the aqueous phase is more

polar than that located above the interface. This

was found by measuring the contact angles of the

nanoparticle film (Figure 4d). The measurements

were performed on the monolayers transferred on

a glass plate by upstroke and downstroke

deposition. The wettability of a single

nanoparticle was calculated from the Cassie

equation. The contact angles of both hemispheres

were 92° and 81°, respectively. This indicated

non-uniform distribution of the ligands on the

surface of gold nanoparticles (Figure

4d). Theoretically, ligand reorganization can

occur either during the ligand exchange reaction

or after the deposition of the nanoparticles at the

interface. In order to elucidate the proper

scenario, we measured infrared spectra of

nanoparticles collected from the solution and the

interface (Figure 4e). We found that the

stretching bands of the methylene groups are

shifted towards shorter wavelengths after the

deposition of the nanoparticles at the

interface. We also calculated the charge density

of the monolayer as 5.4x10-3

C/m2. The presence

of positive electric charge may be useful for detection of biological species, most of which are

negatively charged. This method of fabrication of nanoparticle monolayers is versatile. Instead of gold

nanoparticles one can use particles made of other metals. It is also possible to render the monolayer

negatively charged using thiol ligands with a carboxylate group. Due to its high application potential,

the method was patented.

We inquired on the behavior of these nanoparticles in systems composed of two liquids

(article 3, Figure 5a). We envisioned their spontaneous self-assembly at liquid interfaces due to

amphiphilic properties. To this end, various oil-water biphasic mixtures were tested. We found that

after addition of water the nanoparticles dispersed in methylene chloride migrate onto the interface to

form a dense monolayer. As in the previous case, the distribution of nanoparticles in both phases and

at the interface depends on TMA content in the ligand shell of the nanoparticles. At content of about

13% all nanoparticles move onto the interface. This takes at least a few hours. Since the process of

Figure 5. Self-assembly of nanoparticles at an oil-water interface (Article 3): a) Illustration and photograph of the experiment; b) Wettability and structure of the nanoparticle monolayer deposited on solid support; c) SAXS spectrum of the nanoparticle monolayer at the oil-water interface; d) SEM of the self-assembled nanoparticle monolayer deposited on silicon .

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self-assembly is very slow, the structures formed are well ordered. SEM imaging showed the

formation of hexagonally close-packed nanoparticle monolayers with an area of several square

centimeters (Figure 5d). This is the first literature report on the preparation of such a monolayer by

autonomous self-assembly, i.e. without any outside interference. Note that in previous reports only

small clusters of ordered nanoparticles were obtained. As already mentioned, long-range ordering is

mainly due to the long timespan of the process. We also found that the self-assembly is affected by

methanol used in minute amounts (<1% v/v) to improve the dispersibility of the nanoparticles in

methylene chloride. In control experiments performed in the absence of methanol, highly ordered

arrays were not achieved. This is probably due to the amphiphilicity of methanol molecules, which, in

biphasic systems, accumulate at aqueous interfaces.42

Subsequently, the degree of dissociation of

TMA+X

-groups decreases, enabling the nanoparticles to come closer to each other. The formation of a

hexagonally ordered monolayer at the interface was confirmed by small-angle X-ray scattering

(SAXS) performed in situ (Figure 5c). The integration of the diffraction spectra showed that the

distance between nanoparticles corresponds to hexagonal close-packing. Interestingly, the nanoparticle

film displays different polarity at both sides (Figure 4b). This result confirms our previous

observations on the reorganization of nanoparticle ligand shell at liquid interfaces (article 2).

The systems described in articles 2 and

3 represent static self-assembly. The obtained

structures correspond to the thermodynamic

equilibrium of the system. This sort of self-

assembly is widespread both in natural and man-

made systems.43

In contrast, dynamic self-

assembly is very rare and requires a constant

supply of energy.44

When the energy flux stops,

the ordered structures disintegrate. We strove to

construct such a system using our

nanoparticles. Recall that the nanoparticle

surface is coated with two types of ligands which

are responsible for counteractive forces.

Theoretically, by weakening or strengthening

one of the forces one could assemble or

disassemble the nanoparticles in two dimensions.

The experiments were conducted at the air-water

interface. We found that organic solvents

miscible with water cause this type of self-

assembly (article 4 ). A small amount of

tetrahydrofuran (<1 µL) dropped at the interface

causes the nanoparticles to compress

immediately into a compact film (Figure 6a,

DYSA1). This film consists of a densely-packed

monolayer of nanoparticles (Figure 4c and 4d).

The process of compression is reversible. With

time, the edges of the film smoothen until

complete disintegration of the compressed

layer. After addition of another portion of

solvent the layer is squeezed again, and after a

few days it returns to the equilibrium state. This

process of assembly-disassembly can be repeated many times. The compression occurs due to creation

Figure 6. Dynamic self-assembly of nanoparticles at the air-water interface (Article 4): a) Experimental set-up 1 (DySA1); b) Experimental set-up 2 (DySA2); c) SEM image of the compressed nanoparticle monolayer deposited on silicon; d) SAXS spectrum of the compressed nanoparticle monolayer at the interface; e) Preparation of self-erasing nanoparticle patterns at the interface.

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of surface tension gradient. The particles move toward the area of higher surface tension to balance

capillary forces acting on them. The largest change in surface tension was observed for

tetrahydrofuran, which is the most effective solvent for monolayer compression. We noted a

correlation between the efficiency of the solvent and its relative miscibility with water, as expressed

by the Hildebrand solubility parameter. The most effective solvent, tetrahydrofuran, exhibits the

lowest value. The degree of compression correlates also with dielectric constants of

solvents. However, the possible electrostatic screening mechanism was ruled out after experiments

with electrolyte solutions. We found that changes in the permittivity did not affect the interfacial

nanoparticles. Experiments with surfactants and hydrophobic nanoparticles ultimately confirmed the

capillary mechanism. In the presence of surfactants, which also create a surface tension gradient, the

compression of nanoparticles was observed. It should be noted that in this case the process of self-

assembly is irreversible since the surfactant is accumulated at the interface. As in the case of solvents,

the less soluble surfactants were the most effective. The surface tension gradient affects also

electrically neutral hydrophobic nanoparticles. In this case, the process of self-assembly is also

irreversible due to strong attractive interactions between the nanoparticles. These results show that

dynamic self-assembly is possible if two conditions are met. First, the nanoparticles must repulse and

attract simultaneously. Second, the supplied energy must dissipate. In our case, the energy is

dissipated through the diffusion of the solvent into the bulk phase.

As already mentioned, the DySA1 system has short response and long relaxation times. The

disintegration of the film caused by Brownian motion is slow due to strong interactions between the

hydrophobic chains of adjacent nanoparticles. We found that these interactions can be mitigated using

organic solvents, e.g. tetrahydrofuran. That is, the same solvent causes the compression and

decompression of the monolayer. Based on this finding we developed a new dynamic system

characterized by fast response and relaxation (Figure 6a, DySA2). In the new system, the air-water

interface was initially saturated with tetrahydrofuran. The saturation was performed by placing the

DySA1 system in a desiccator filled with tetrahydrofuran vapors. In this manner the surface tension

gradient was not created and the nanoparticles were uniformly dispersed at the interface. Then, after

directing an air flow toward the interface, the nanoparticles immediately self-assembled into a

compact film. It should be noted that the self-assembly occurred at the place to which the air stream

was targeted. When the air supply ceased, the nanoparticles returned in a few seconds to the initial

configuration. Cycles of compression-decompression can be repeated at least for a dozen times. The

mechanism of self-assembly in this case is the same as for DySA1. The air jet causes localized

evaporation of tetrahydrofuran, thereby creating the gradient of surface tension. The nanoparticles

move to the place of evaporation of the solvent, where the surface tension is higher. After removal of

the gas source, the gradient instantly vanishes due to diffusion of tetrahydrofuran vapors over the

interface, weakening the hydrophobic interactions between the nanoparticles.

The dynamic systems presented herein have a great application potential. The system denoted

as DySA1, thanks to short relaxation time, can be considered as a chemical analogue to the Langmuir-

Blodgett technique which does not require any cumbersome equipment. For this reason, it was

submitted for patent application. On the other hand, DySA2, due to fast response and relaxation, can

be a prototype for intelligent devices. We demonstrated that DySA2 can be used for creating self-

erasing patterns (Figure 6e).

The dense monolayers described in articles 2-4 exhibit moderate stability due to non-covalent

interactions between the nanoparticles. Although they can be successfully used as coatings and

responsive systems, they are not robust enough to fabricate nanoporous materials. The latter may be

applicable for the filtration of particles differing by size and the sign of electrical charge. The walls of

capsules used in catalysis and drug delivery systems are also composed of nanoporous films. Thus, in

subsequent studies, we focused on the stabilization of the nanoparticle monolayers at the liquid

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interfaces. We sought for functional groups capable to covalently cross-link the nanoparticles. We

chose the carbon-carbon double bond because it undergoes polymerization and olefin metathesis

reactions under mild conditions. It turned out that the olefin bond is incompatible with the thiol group

(-SH). We found that the thiols (R-SH) can be substituted by xanthates [R-SC(S)OEt], which also

react with the surface of gold nanoparticle to give the Au-SR bond (article 5 , Figure 7a). This enabled

us to introduce various functional groups

including unsaturated bonds on the nanoparticle

surface. As followed by NMR, the conversion of

xanthate to thiol takes place both in solution and

on the nanoparticle surface. According to UV-

Vis, the formation of the gold-thiolate bonds is

complete within one hour (Figure 7b). The

chemical composition of the nanoparticles was

analyzed by NMR and XPS. NMR showed the

presence of the functional groups in the ligand

shell of the nanoparticles (Figure 7c). XPS

spectra revealed the physically (Au-HSR) and

chemically (Au-SR) adsorbed thiols on the gold

surface (blue and red component in sulfur

spectrum, respectively, Figure 7d). At the same

time, we discovered an alternative mode for the

hydrogen loss in the reaction of thiols with

metallic gold. It was thought previously that the

reaction occurs with the evolution of molecular

(or atomic) hydrogen.45

Our study demonstrated

for the first time that hydrogen can be released as

a proton. Notably, this path has been recently

confirmed by other researchers.46

It should be

also noted that we have been granted a patent for

the xanthate method of nanoparticle

functionalization.

We used the above method for modifying

the amphiphilic nanoparticles with olefinic

groups. The nanoparticles we prepared were structurally similar to those described in works 2-4. In a

few cases, we succeeded in obtaining chemically stabilized dense monolayers at planar oil-water

interfaces. The experiments, however, were very unreproducible. Moreover, thus prepared

nanoparticles, despite their amphiphilicity, did not self-assemble at curved interfaces, that is, in

emulsions. Therefore, we decided to replace TMA with a methacrylate group, which is amphiphilic

and contains an olefinic bond (article 6 , Figure 8a). We found that the nanoparticles modified by this

group self-assemble in emulsions to give very stable three-dimensional structures, i.e. capsules.

Depending on the composition of the dispersed phase capsules of various size and wall thickness were

produced. In toluene, small capsules (about 150 nm) with thick walls made of nanoparticle multilayers

were formed (Figure 4c). In hexadecane-toluene mixtures, the capsule size increased and the wall

thickness decreased. At hexadecane contents exceeding 5% v/v, the capsule size was about 500 nm

and the wall consisted of a single nanoparticle monolayer. According to DLS, the capsules were very

stable and their size did not change for months. The capsules, however, were ruptured under electron

beam during SEM analysis. This problem was easily solved by strengthening the capsule walls with

ultraviolet light. Upon irradiation, the nanoparticles in the capsule wall were cross-linked through

Figure 7. The synthesis of thiol-coated gold nanoparticles using xanthates (Article 5): a) Reaction scheme; b) Reaction kinetics (UV-Vis); c) NMR spectra of the nanoparticles before and after the desorption of ligands; d) Gold and sulfur XPS spectra of the nanoparticles.

13

polymerization of the olefinic bonds on their surface. Further studies showed that the distribution of

nanoparticles in the emulsion depends on the wettability of the nanoparticle surface. At the toluene-

water interfaces the contact angle is significantly higher than 90° (Figure 4b), and therefore, the

nanoparticles prefer the oil phase. Since the nanoparticles were used in excess, that is, more than the

interface can accommodate, capsules with thick walls were produced. A thick wall enables the

stabilization of smaller capsules owing to steric effects. After dilution of toluene with hexadecane, the

contact angle drops and the adsorption of the

nanoparticles at the interface becomes favorable.

The increase of hexadecane content impairs also

the dispersibility of the nanoparticles in the oil

phase. Consequently, the wall thickness decreases.

At hexadecane content above 5% v/v, regardless of

the initial amount of the nanoparticles, capsules

composed of a single monolayer are formed,

whereas the excess nanoparticles precipitate out of

the emulsion. Steric effects in this case are

insignificant, and therefore, the capsules exhibit

larger sizes. The wettability of the nanoparticles

can be also regulated by changing the composition

of their ligand shell. The ligand-exchange reaction

is performed in situ. In the presence of a polar

MUTEG ligand, the contact angle decreases and

the nanoparticles move onto the interface. In this

method, smaller and thinner-walled capsules are

produced due to better stabilization of the interface

(Figures 8d and 8e). It is known that nanoparticles

with heterogeneous coating reduce the surface

tension more effectively than homogeneous ones.47-

50 Similarly, as in the previous experiments

(articles 2-3), the reorganization of the ligand shell

probably takes place in this case. The higher

interfacial activity of the modified nanoparticles

was confirmed by measurements of the contact

angle. The contact angle drops to 90° at MUTEG

loading as low as 5 mol%. It should be noted that

the values of contact angles are estimated as they

were measured on the surface of macroscopic

gold. Interestingly, the interfacial activity of the

nanoparticles can also be gauged from the UV-Vis

spectra. In toluene-water emulsions, the location of

the nanoparticle plasmon band is similar to that in

pure toluene (blue and black component,

respectively, in Figure 8f). This is because of good

dispersibility of the nanoparticles in toluene and

their poor adsorption at the interface. When the emulsion is prepared in the presence of hexadecane or

MUTEG ligand (red and green component in Figure 8f), the plasmon band is shifted significantly

towards longer wavelengths. This indicates the entrapment of the nanoparticles at the interface and

shortening the distances between them.

Figure 8. Self-assembly of nanoparticles at an oil-water interface in emulsions (Article 6): a) Experimental set-up; b) Dependence of the capsule size and contact angle on hexadecane content in the oil phase; c) Dependence of the thickness of capsule wall on hexadecane content in the oil phase; d) Dependence of the capsule size on MUTEG loading; e) SEM image of the capsules after ligand-exchange; f) UV-Vis spectra of the nanoparticles in bulk phase and at the interfaces; g) Fluorescence spectra of the capsules before and after the cargo release.

14

As already mentioned, the capsules display high stability because of the covalently cross-

linked wall. They also exhibit low permeability - even those composed of a single nanoparticle

monolayer. This property can be used for encapsulation and controlled release of chemical

substances. The cargo should be proportional to or larger then pores formed in the capsule wall after

hexagonal close packing of the nanoparticles at the interface. In our experiments we used highly

fluorescent bisimide perylene dye as a cargo, whose size is comparable with the size of the pores.

Fluorescence measurements showed that the capsules were not leaching (red component, Figure

8g). The dye was released only after the dissolution of capsule walls with potassium cyanide (green

component, Figure 8g).

Summary:

I developed a halogen-free method for the synthesis of gold nanoparticles by the reduction of

gold(III) oxide with aliphatic amines. The method provides particles with an average size

below 10 nm and reasonable polydispersity. The nanoparticles, due to the presence of labile

amine ligands, are perfectly suitable for further functionalization with thiol ligands.

Importantly, the synthetic protocol is general and applicable for the preparation of other

precious metal nanoparticles from the corresponding metal oxides. Furthermore, the method,

because of the lack of halide ions, enables efficient alloying of metals when preparing

bimetallic nanoparticles.

I developed a new method for the functionalization of inorganic nanoparticles with thiol

ligands using organic xanthates. The method is particularly useful for the decoration of

nanoparticles with functional groups incompatible with the thiol group, e.g. unsaturated

carbon-carbon bonds.

I discovered a new path of hydrogen release in the reaction of thiols with nanoscopic gold.

This reaction is extremely important for nanotechnology as it is used for creating self-

assembling monolayers. I demonstrated that hydrogen can be released not only as a gas but

also as a proton.

I developed the first nanoscopic system undergoing both static and dynamic self-assembly. To

this end, I designed and prepared charged gold nanoparticles coated with hydrophobic and

hydrophilic ligands. In an oil-water system, the nanoparticles spontaneously self-assemble into

a hexagonally close-packed monolayer at the interface of two liquids. In a gas-liquid system,

the nanoparticles require a constant supply of energy to form such a monolayer. The energy is

delivered to the system by air flow. When the air flow ceases, the nanoparticle monolayer

disassembles.

I developed a number of methods for the fabrication of large-area densely packed nanoparticle

monolayers. The first method involves the mechanical compression of the nanoparticles at the

air-water interface. The second method is the static self-assembly of the nanoparticles at the

oil-water interface. The third method is based on the dynamic self-assembly of the

nanoparticles and can be considered as a chemical analogue to the first method.

I developed a method for the fabrication of capsules smaller than one micron made of

nanoparticle monolayers. This is the first report on the fabrication of submicron capsules

through changes in nanoparticle wettability. The method, unlike other approaches, enables the

production of capsules of tunable size and wall thickness. The resulting capsules are robust

and tight, and can be used for chemical encapsulation and release.

15

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3. List of other publications

3.1 Papers published before the doctoral degree

1. Sashuk, V.; Koszarna, B.; Winiarek, P.; Gryko, D.T.; Grela, K. The simple synthesis of stable

A3- and trans-A2B-molybdenum(V) corrolates. Inorg. Chem. Commun. 2004, 7, 871-875. IF:

1,762.

I developed the method of synthesis of molybdenum corrolates and defined their structure; I

was also involved in writing the manuscript.


2. Michrowska, A.; Bujok, R.; Harutyunyan, S.; Sashuk, V.; Dolgonos, G.; Grela, K. Nitro-

Substituted Hoveyda-Grubbs Ruthenium Carbenes: Enhancement of Catalysts Activity

through Electronic Activation. J. Am. Chem. Soc. 2004, 126, 9318-9325. IF: 13,038.

I prepared ruthenium catalysts and tested their activity and selectivity in enyne metathesis; I

also was involved in writing the manuscript.


18

3. Sashuk, V.; Ignatowska, J.; Grela, K. A Fine-Tuned Molybdenum Hexacarbonyl/Phenol

Initiator for Alkyne Metathesis. J. Org. Chem. 2004, 69, 7748-7751. IF: 4,785.

I prepared molybdenum hexacarbonyl-based catalysts and tested their activity and selectivity

in alkyne metathesis; I was also involved in writing the manuscript.


4. Mikus, A.; Sashuk, V.; Kędziorek, M.; Samojłowicz, C.; Ostrowski, S.; Grela, K. Olefin and

Enyne Cross-Metathesis–New Tool for Synthesis of Alkenyl-substituted Azulenes. Synlett

2005, 1142-1146. IF: 2,323.

I prepared ruthenium catalysts and tested their activity and selectivity in the metathesis of

alkenyl and alkynyl derivatives of azulene with alkenes; I was also involved in writing the

manuscript.


5. Sashuk, V.; Grela, K. Synthetic and Mechanistic Studies on Enyne Metathesis: A Catalyst

Influence. J. Mol. Catal. A: Chem. 2006, 257, 59-66. IF: 3,958.

I prepared ruthenium catalysts and tested their activity and selectivity in enyne metathesis; I

prepared the text of the manuscript.


3.2 Papers published after the doctoral degree

1. Grela, K.; Michrowska, A.; Bieniek, M.; Sashuk, V.; Szadkowska, A. Phosphine-Free EWG-

activated Ruthenium Olefin Metathesis Catalysts: Design, Preparation and Applications in

NATO Science Series, Series II: Mathematics, Physics and Chemistry "Metathesis Chemistry:

From Nanostructure Design to Synthesis of Advanced Materials", Imamoglu, Y.; Dragutan, V.

Eds.; Springer-Verlag, Berlin, 2007, 243, 111-124.

I tested the activity and selectivity of ruthenium catalysts in the metathesis of alkenyl and

alkynyl derivatives of azulene with alkenes.


2. Czernuszewicz, R.S.; Mody, V.; Zareba, A.A.; Zaczek, M.B.; Galezowski, M.; Sashuk, V.;

Grela, K.; Gryko, D.T. Solvent-Dependent Resonance Raman Spectra of High-Valent

Oxomolybdenum(V) Tris[3,5-bis(trifluoromethyl)phenyl]corrolate. Inorg. Chem. 2007, 46,

5616-5624. IF: 4,820.

I developed the method of synthesis of oxomolybdenum corrolate complexes.


3. Sashuk, V.; Samojłowicz, C.; Szadkowska, A.; Grela, K. Olefin cross-metathesis with vinyl

halides. Chem. Commun. 2008, 21, 2468-2470. IF: 6,567.

I prepared ruthenium catalysts and tested their activity and selectivity in the metathesis of

olefins with vinyl halides; I was also involved in writing the manuscript.


4. Sashuk, V.; Schoeps, D.; Plenio, H. Fluorophore tagged cross-coupling catalysts. Chem.

Commun. 2009, 22, 770-772. IF: 6,567.

“Highlights” in Chemical Science (Chem. Sci., 2009, 6, C18)

I developed the method of synthesis of a fluorophore-labeled palladium catalyst and studied

the catalysis; I was also involved in writing the manuscript.


5. Schoeps, D.; Sashuk, V.; Ebert, K.; Plenio, H. Organophilic Nanofiltration of enlarged

(NHC)PdCl(allyl) derived Catalysts in Cross Coupling Reactions. Organometallics 2009, 28,

3922-3927. IF: 4,186.

19

I developed the method of synthesis of NHC ligands with chlorobenzyl units.


6. Sashuk, V.; Peeck, L.H.; Plenio, H. (NHC)(NHCewg)RuCl2(CHPh) Complexes with

modified NHCewg Ligands for efficient Ring Closing Metathesis. Chem. Eur. J. 2010, 16,

3983-3993. IF: 5,771.

I developed the method of synthesis of ruthenium catalysts (incl. those labeled with a

fluorophore) containing two NHC ligands and tested their activity in the creation of

tetrasubstituted C-C double bonds; I was also involved in writing the manuscript.


7. Kamińska, A.; Dzięcielewski, I.; Weyher, J.L.; Waluk, J.; Gawinkowski, S.; Sashuk, V.;

Fiałkowski, M.; Sawicka, M.; Suski, T.; Porowski, S.; Hołyst, R. Highly reproducible, stable

and multiply regenerated surface-enhanced Raman scattering substrate for biomedical

applications. J. Mater. Chem. 2011, 21, 8662-8669. IF: 6,626.

I developed the method of regeneration of substrates for SERS.


8. Hou, S.; Ziębacz, N.; Wieczorek, S.A.; Kalwarczyk, E.; Sashuk, V.; Kalwarczyk, T.;

Kamiński, T.S.; Hołyst, R. Formation and structure of PEI/DNA complexes: quantitative

analysis. Soft Matter 2011, 7, 6967-6972. IF: 3,798.

I performed measurements of the zeta potential.


9. Bieniek, M.; Samojłowicz, C.; Sashuk, V.; Bujok, R.; Śledź, P.; Lugan, N.; Lavigne, G.; Arlt,

D.; Grela, K. Rational design and evaluation of upgraded Grubbs/Hoveyda olefin metathesis

catalysts: polyfunctional benzylidene ethers on the test bench. Organometallics 2011, 30,

4144-4158. IF: 4,186.

I prepared and examined the stability of ruthenium catalysts; I also tested their activity and

selectivity in olefin and enyne metathesis.


10. Danylyuk, O.; Fedin, V.P.; Sashuk, V. Kinetic trapping of the host-guest association

intermediate and its transformation into a thermodynamic inclusion complex. Chem. Commun.

2013, 49, 770-772. IF: 6,567.

I performed NMR measurements; I was also involved in writing the manuscript.


11. Danylyuk, O.; Fedin, V.P.; Sashuk, V. Host-guest complexes of cucurbit[6]uril with

isoprenaline: the effect of the metal ion on the crystallization pathway and supramolecular

architecture. CrystEngComm 2013, 15, 7414-7418. IF: 3,849.

I performed NMR measurements; I was also involved in writing the manuscript.


12. Dolińska, J.; Jönsson-Niedziółka, M.; Sashuk, V.; Opałło, M. The effect of electrocatalytic

nanoparticle injection on the electrochemical response at a rotating disc electrode.

Electrochem. Commun. 2013, 37, 100-103. IF: 4,569.

I synthesized nanoparticles for the study.


13. Dolińska, J.; Kannan, P.; Sashuk, V.; Kaszkur, Z.; Sobczak, J.W.; Jönsson-Niedziółka, M.;

Opałło, M. The versatile electrocatalytic oxidation of glucose on bimetallic nanoparticulate

film electrode. J. Electrochem. Soc. 2014, 161, H3088-H3094. IF: 3,014.



20

14. Karczmarczyk, A.; Celebańska, A.; Nogala, W.; Sashuk, V.; Chernyaeva, O.; Opałło, M.

Electrolytic glucose oxidation at gold and gold-carbon nanoparticulate film prepared from

oppositely charged nanoparticles. Electrochim. Acta 2014, 117, 211-216. IF: 4,803.



15. Dolińska, J.; Kannan, P.; Sashuk, V.; Jönsson-Niedziółka, M.; Kaszkur, Z.; Lisowski, W.;

Opałło, M. Electrocatalytic synergy on nanoparticulate films prepared from oppositely

charged Pt and Au nanoparticles. ChemElectroChem 2014, 1, 1023-1026. IF: 3,506.



16. Danylyuk, O.; Sashuk, V. Solid-state assembly of carboxylic acid substituted pillar[5]arene

and its host-guest complex with tetracaine. CrystEngCommun 2015, 17, 719-722. IF: 3,849.

I synthesized the macrocyclic compound and performed NMR measurements; I was also

involved in writing the manuscript.


17. Dolińska, J.; Chidambaram, A.; Taleat, Z.; Adamkiewicz, W.; Lisowski, W.; Palys, B.;

Hołdyński, M.; Andryszewski, T.; Sashuk, V.; Rassaei, L.; Opałło, M. Decoration of MoS2

Nanopetal Stacks with Positively Charged Gold Nanoparticles for Synergistic Electrocatalytic

Oxidation of Biologically Relevant Compounds. Electrochim. Acta. 2015, 182, 659-667. IF:

4,803.



18. Sashuk, V.; Butkiewicz, H.; Fiałkowski, M.; Danylyuk, O. Triggering sequential reaction by

host-guest interactions. Chem. Commun. 2016, 52, 4191-4194. IF: 6,567.

I am the author of the idea and research concept; I performed the experimental part; I

prepared the graphical material for publication, wrote the manuscript, corresponded with

editor during the submission of the manuscript, and prepared responses to the reviewers.


19. Danylyuk, O.; Butkiewicz, H.; Sashuk, V. Host-guest complexes of cucurbit[6]uril with the

trypanocide drug diminazene and its degradation product 4-aminobenzamidine.

CrystEngCommun, 2016, 18, 4905-4908. IF: 3,849.

I synthesized the macrocyclic compound; I was also involved in writing the manuscript.


20. Sashuk, V.; Danylyuk, O. A Thermo- and Photo-Switchable Ruthenium Initiator For Olefin

Metathesis. Chem. Eur. J. 2016, 22, 6528-6531. IF: 5,771.

I am the author of the idea and research concept; I performed the experimental part; I

prepared the graphical material for publication, wrote the manuscript, corresponded with the

editor during the submission of the manuscript, and prepared responses to the reviewers.


4. Patents and patent applications

1. Sashuk, V., Kamińska, A., Hołyst, R., Fiałkowski, M. The use of ammonia and hydrogen

peroxide solution for cleaning the Surface Enhanced Raman Spectroscopy platforms containing a

layer of gold. P-392461, 2010.

2. Sashuk, V., Kamińska, A., Hołyst, R., Fiałkowski, M. The use of borohydride solution for

cleaning the Surface Enhanced Raman Spectroscopy platforms containing a layer of gold. P-

392460, 2010; CH 01477/11, 2011; CH 703842, 2013.

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4. Sashuk, V., Fiałkowski, M., Hołyst, R. Nanoparticles covered with hydrophilic ligands, layer of

the nanoparticles and surface covered thereof. P-393843, 2011; DE102012100467.6, 2012; PL

220925, 2015.

5. Sashuk, V., Fiałkowski, M., Hołyst, R. A method for covering nanoparticles with a layer of thiol

ligands. P-399797, 2012; PL 220832, 2015.

6. Sashuk, V., Winkler, K., Fiałkowski, M., Hołyst, R. The method of preparation of the monolayer

composed of densely packed layer of nanoparticles covered with hydrophilic and hydrophobic

ligands, the monolayer and the use thereof for covering the surface. P-404256, 2013.

7. Sashuk, V. Precursor of chelating carbene ligand, isomeric complexes containing chelating

ligand formed from the precursor, and the use thereof as olefin metathesis catalysts. P-415722,

2016.

5. Conference presentations

1. Sashuk, V.; Ignatowska, J.; Grela, K. „A Fine-Tuned Molybdenum Hexacarbonyl/Phenol

Initiator for Alkyne Metathesis”, Recent Advances In Organometallic Chemistry and Applied

Catalysis (PreOMCOS13), Paris, France, 15-16.07.2005. Oral presentation


Initiator for Alkyne Metathesis”, The 16th International Symposium on Olefin Metathesis and

Related Chemistry (ISOM16), Poznań, Polanda, 07-12.08.2005. Poster


Initiator for Alkyne Metathesis”, XXI Conference on Isoprenoids, Białowieża, Poland, 23-

29.09.2005. Oral presentation


Initiator for Alkyne Metathesis”, European Congress of Young Chemists (YoungChem2005),

Rydzyna, Poland, 12-16.10.2005. Oral presentation


Initiator for Alkyne Metathesis”, Graduiertenkolleg Symposium "Synthetic, Mechanistic and

Reaction-Engineering Aspects of Metal Containing Catalysts, Berlin, Germany, 17-18.11.2005.

Poster

6. Sashuk, V.; Fiałkowski, M. „Charged nanoparticles at a gas-liquid interface”, Microsymposium

of the Institute of Physical Chemistry PAS, Warsaw, Poland, 11-13.01.2011. Poster

7. Sashuk, V.; Fiałkowski, M. „Self-Assembly of Charged Nanoparticles into Monolayers at

Air/Liquid and Liquid/Liquid Interfaces”, NanoToday Conference, Hawaii, USA, 11-15.12.2011.

Oral presentation

8. Sashuk, V.; Fiałkowski, M. „Creating ultrathin films via self-assembly of charged nanoparticles

at fluid interfaces”, NanoSEA2012, Sardinia, Italy, 25-29.06.2012. Oral presentation

9. Sashuk, V. „Self-assembly of charged nanoparticles at fluid interfaces”, 4th EuCheMS Chemistry

Congress, Prague, Czech Republic, 26-30.08.2012. Oral presentation

10. Sashuk, V. „Thiolate-protected nanoparticles via organic xanthates: mechanism and

implications”, 1st Warsaw-Cambridge Young Scientists Meeting „Breaking Boundaries in

Chemistry”, Warsaw, Poland, 08-09.03.2013. Oral presentation

11. Sashuk, V. „Thiolate-protected nanoparticles via organic xanthates: fundamental and practical

aspects”, International Symposium on Macrocyclic and Supramolecular Chemistry, Arlington,

USA, 07-11.07.2013. Poster

22

12. Sashuk, V. „Self-assembly of xanthates into thiolate monolayers on the surface of gold

nanoparticles”, 56 PTChem and SITPChem Convention, Siedlce, Poland, 16-20.09.2013. Oral

presentation

13. Sashuk, V.; Winkler, K.; Żywociński, A.; Wojciechowski, T.; Górecka, E.; Fiałkowski, M.

„Nanoparticles in a capillary trap: dynamic self-assembly at fluid interfaces”, Microsymposium

of the Institute of Physical Chemistry PAS, Warsaw, Poland, 13-15.01.2014. Oral presentation

14. Sashuk, V. „Thiolate-protected nanoparticles via organic xanthates: fundamental and practical

aspects”, Microsymposium of the Institute of Physical Chemistry PAS, Warsaw, Poland, 13-

15.01.2014. Poster

15. Sashuk, V. „Dynamic self-assembly of charged nanoparticles at fluid interfaces”, International

Symposium on Nanostructured Functional Materials (NanoFunMat2014), Pułtusk, Poland, 15-


16. Sashuk, V.; Butkiewicz, H.; Danylyuk, O. „Triggering sequential reaction by host-guest

interactions”, 15th International Seminar on Inclusion Compounds, Warsaw, Poland, 17-


17. Sashuk, V.; Butkiewicz, H.; Fiałkowski, M.; Danylyuk, O. „Triggering autocatalytic reaction by

host-guest interactions”, Microsymposium of the Institute of Physical Chemistry PAS, Warsaw,

Poland, 10-12.01.2017. Oral presentation

6. Invited talks

1. Sashuk, V. „Assembling nanoparticles at fluid interfaces”, Polish-Korean Organic Chemistry

Symposium, Warsaw, 10.05.2016.

2. Sashuk, V. „Synthesis and self-organization of nanoparticles at fluid interfaces”, Poznan

University of Technology, Poznań, 24.05.2016.

3. Sashuk, V. „Synthesis and organization of nanoparticles at fluid interfaces”, University of

Białystok, Białystok, 02.06.2016.

7. Research projects

1. Grant of the Volkswagen Stiftung Foundation, I/77 592, „Alkyne Metathesis. Catalysts and

applications in organic synthesis”, Institute of Organic Chemistry PAS, Warsaw, 2002-2004,

contractor.

2. Grant of the Ministry of Science and Higher Education of Poland (Committee of Scientific

Research), 3 T09A 026 028, „Studies on enyne metathesis: new catalysts and applications in

organic synthesis”, Institute of Organic Chemistry PAS, Warsaw, 2005-2007, contractor.

3. Grant of the Ministry of Science and Higher Education of Poland, POIG.01.01.02-00-008/08, „

Quantum semiconductor nanostructures for applications in biology and medicine -

Development and commercialization of a new generation of molecular diagnostics based on

new Polish semiconductor devices", Institute of Physical Chemistry PAS, Warsaw, 2007-2014,

liaison officer and contractor.

4. Grant of the Ministry of Science and Higher Education of Poland, Iuventus Plus IP2010

036970, „ The use of metathesis for the preparation of nanocomposite materials ", Institute of

Physical Chemistry PAS, Warsaw, 2010-2011, principal investigator.

23

5. Grant of the National Science Centre, Sonata UMO-2011/01/D/ST5/03518, „ Self-assembly of

nanoparticles at fluid interfaces: towards new nanostructured materials”, Institute of Physical

Chemistry PAS, Warsaw, 2011-2014, principal investigator.


048271; „Charged nanoparticles at interfaces: controlled integration in two dimensions”,

Institute of Physical Chemistry PAS, Warsaw, 2012-2013, principal investigator.

7. Grant of the National Science Centre, Sonata UMO-2011/03/D/ST5/05486, „ Supramolecular

complexes of cucurbiturils as crystalline functional materials: synthesis, studies of structure

and properties”, Institute of Physical Chemistry PAS, Warsaw, 2012-2015, contractor.


050772, „Synthesis of pillar[n]arene derivatives for molecular recognition in water”, Institute

of Physical Chemistry PAS, Warsaw, 2013-2015 principal investigator.

9. Grant of the National Centre for Research and Development, PBS2/A1/8/2013, „ Development

of commercial production methods of SERS substrates for ultrasensitive and rapid biomedical

analysis”, Institute of Physical Chemistry PAS, Warsaw, 2013-2015, contractor.

10. Grant of the National Science Centre, Sonata Bis UMO-2014/14/E/ST5/00778,

„Photoswitchable catalysis on the surface of colloidal particles”, Institute of Physical

Chemistry PAS, Warsaw, 2015-2020, principal investigator.

8. Evaluation activity

1. Expert of the National Science Centre

2. Reviewer of the American Chemical Society

9. Science popularization

1. The organization of classes and presentations for talented youth in the workshop organized by

the Institute of Physical Chemistry PAS and Polish Children's Fund;

2. Materials promoting Polish science:

a) Fiałkowski, M.; Sashuk, V. Preparation of thin films of nanoparticles in “Institute of

Physical Chemistry of Polish Academy of Sciences”, Kapuścińska-Bernatek, A.;

Luboradzki, R.; Chrostowski, J. Eds.; Institute of Physical Chemistry PAS, Warsaw, 2012,

76-77.

b) Sashuk, V. Static and dynamic 2D structures self-assembled from charged gold

nanoparticles in “Annual Report 2014, Polish Academy of Sciences”, Chmielewski, M.C.

Ed.; Office of Science Promotion, Warsaw, 2014, 56-57.

3. Popular science presentations of own research in the form of press releases on the websites:

http://ichf.edu.pl/press/2012/02/index120208_PL.html

http://naukawpolsce.pap.pl/aktualnosci/news,388009,w-ichf-pan-opracowano-nowe-metody-

nanoszenia-nanowarstw.html

http://www.sofizmat.pl/tekst/143

10. Teaching activity

1. Supervision of bachelor theses:

http://ichf.edu.pl/press/2012/02/index120208_PL.html

http://naukawpolsce.pap.pl/aktualnosci/news,388009,w-ichf-pan-opracowano-nowe-metody-nanoszenia-nanowarstw.html

http://naukawpolsce.pap.pl/aktualnosci/news,388009,w-ichf-pan-opracowano-nowe-metody-nanoszenia-nanowarstw.html

http://www.sofizmat.pl/tekst/143

24

a) Arkadiusz Kalinowski. „Fabrication of nanostructured materials in the coordination sphere

of gold using metathesis”, 2013;

b) Grzegorz Sobczak. „Self-assembly of amphiphilic gold nanoparticles in oil-in-water

emulsions”, 2014;

c) Konrad Rogaczewski. „Gold nanoparticles obtained by the reduction of gold(III) oxide with

primary aliphatic amines”, 2016.

2. Supervision of master theses:

a) Arkadiusz Kalinowski. „Self-assembly of nanoparticles into chemically reinforced

structures at liquid interfaces”, 2014;

b) Sandra Iskorościńska. „Synthesis of pillar[n]arene derivatives of zwitterionic structure”,

2014;

c) Grzegorz Sobczak. „Light controlled self-assembly of gold nanoparticles”, 2016.

3. Supervision of doctoral theses:

a) Sandra Iskorościńska, in progress;

b) Magdalena Szewczyk, in progress;

c) Grzegorz Sobczak, in progress.

11. Prizes and awards

1. University diploma with honors, 2002.

2. Award for the best paper published in the Institute of Physical Chemistry PAS in 2012 (article

No. 5), 2013.

3. Award in ‘Young researchers of the Institute of Physical Chemistry PAS’ contest, 2013.

4. Scholarship for outstanding young scientists, Ministry of Science and Higher Education of

Poland, 2013-2016.

5. Włodzimierz Kołos Prize, Polish Academy of Sciences, 2013.



12. Summary of all scientific achievements

Total number of publications: 31

-as the first author: 13

-as the corresponding author: 8

Sum of IF3: 161,849

Number of citations4: 726

Hirsch Index4: 13

3 Acc. to Journal Citation Reports on 01.02.2017

4 Acc. to Web of Science on 01.02.2017

summary of professional accomplishmentsichf.edu.pl/r_act/hab/sashuk_autoreferat_en.pdfthe synthesis...

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