metal nanoparticles for advanced materials: from theory to...

Metal nanoparticles for

advanced materials:

From theory to practice

0103 October 2012, Heraklion, Crete, Greece

Metal nanoparticles for advanced materials: From theory to practice

Metal nanoparticles for advanced materials:

From theory to practice

0103 October 2012,

Heraklion, Crete Greece

Aims and scopeMetal nanoparticles are studied extensively in both experimental and theoretical materials science. Inclusion of nanoparticles in a material allows for tailoring its mechanical, optical and chemical properties. Such advanced nanocomposite materials are used today for catalysis, sensing, biolabeling, plasmonics, photonics, smart coatings and superhard coatings.

This meeting will focus on stateoftheart experimental and theoretical studies of nanoparticles and advanced materials containing nanoparticles.

01-03 October 2012, Heraklion, Crete, Greece 1


Organizers:

Ioannis Remediakis [email protected]

Carla Bittencourt [email protected]

Aristea Maniadaki [email protected]

Invited speakers:

Spiros H. Anastasiadis F ORTH and University of Crete

Alexandra Carvalh o University of Aveiro, Portugal

Mustafa Culha Yeditepe University, Turkey

Frank Dillon Oxford University, UK

Ben Hourahine University of Strathclyde, UK

Nuria Lopez Institut Catala d'Investigacio Quimica (ICIQ), Spain

Marta D. Rossell Center for Electron Microscopy, EMPA Dubendorf, Switzerland

Paul Ziemann Institute of Solid State Physics, Ulm University, Germany


http://www.iesl.forth.gr/people/person.aspx?id=102

http://www.nanotp.org/users/49/38/nanoTP_nologin/paul-ziemann-uni-ulm-de.html

http://www.nanotp.org/users/79/38/nanoTP_nologin/marta-rossell-empa-ch.html

http://www.iciq.es/portal/350/

http://www.nanotp.org/users/45/38/nanoTP_nologin/benjamin-hourahine-strath-ac-uk.html

http://www-em.materials.ox.ac.uk/?firstname=Frank&surname=Dillon

http://www.nanotp.org/users/17/38/nanoTP_nologin/mculha-yeditepe-edu-tr.html

http://www.nanotp.org/users/87/38/nanoTP_nologin/aicarvalho-ua-pt.html

http://www.nanotp.org/users/87/38/nanoTP_nologin/aicarvalho-ua-pt.html

http://www.uoc.gr/

http://www.forth.gr/

http://www.forth.gr/


Monday, 01/10/2012

09:30 Registration 11:30 Ioannis Remediakis

Department of Materials Science and Technology, University of CreteWelcome

Session I: Microscopy of nanoparticles Chair: P.Ziemann

11:50 Three-dimensional characterization of nanoparticles by electron tomography M.D. Rossell1, R. Erni1 , S. Van Aert 2, G. Van Tendeloo 2, K.J. Batenburg 3

1Electron Microscopy Center, EMPA, Swiss Federal Laboratories for Materials Science & Technology, Dübendorf, Switzerland 2Electron Microscopy for Materials Research, EMAT, University of Antwerp, Antwerp, Belgium 3IBBT-Vision Lab, University of Antwerp, Wilrijk, Belgium

12:20 Nanoparticles studied by X-ray microscopy with high spatial and spectral resolutionP. Guttmann, K. Henzler, S. Werner, S. Rehbein, G. SchneiderHelmholtz-Zentrum Berlin für Materialen und Energie GmbH, Institute for Soft Matter and Functional Materials, Berlin, Germany

12:40 Samarium-CNT interaction: HEXPS and HTEMA. A. El Mel1, P. De Marco1, R. Snyders1, C. Bittencourt1, J. Ghijsen2, S. Thiess3, W. Drube3, X. Ke4, G. Van Tendeloo4

1 ChiPS – University of Mons – Belgium 2 LISE - University of Namur – Belgium 3 Deutschen Elektronen Synchrotron DESY, D-22603 Hamburg, Germany 4 EMAT –University of Antwerp – Belgium

13:00Lunch and discussion

Session II: Nanoparticles for catalysis Chair: M.Culha

14:30 Synthesis of Nanocatalysts within pH-responsive Polymeric NanostructuresS. H. Anastasiadis1,2, M. Kaliva,1,3 K. Chistodoulakis,1,3 M.A. Frysali,1,2 L. Papoutsakis1 and M. Vamvakaki1,3 1 Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, Heraklion Crete, Greece 2 Department of Chemistry, University of Crete, Heraklion Crete, Greece 3 Department of Materials Science & Technology, University of Crete,Heraklion Crete, Greece

15:00 Gold nanostructures: challenges and opportunities of wet synthesisN. Lopez, G. Novell-Leruth, Institute of Chemical Research of Catalonia, ICIQ, Tarragona, Spain

15:30 Hydrodechlorination of trichloroethylene over Pd-based nanostructuresK. Honkala, J. AndersinDepartment of Chemistry, Nanoscience Center, University of Jyväskylä, Finland

15:50Coffee around posters

16:30 Customised transition metal oxide nanoparticles for the controlled production of carbon nanostructuresF. Dillon, K. Mandel, A. Ajayan, A. Koos and N. GrobertDepartment of Materials, Parks Road, University of Oxford, Oxford,UK



17:00 Catalysis of novel organic transformations by supported gold nanoparticlesManolis Stratakis Department of Chemistry, University of Crete, Greece

17:20 - 18:00 Poster Session

Tuesday, 02/10/2012

Session III: Nanoparticles in applied science Chair: K. Honkala

9:30 Structural Phase Transitions in FePt Nanoparticles: Chemical & Magnetic ConsequencesL. Han, U. Wiedwald, and P. ZiemannInstitute of Solid State Physics, Ulm University, FRG

10:00 Enhanced performance in organic photovoltaic cells using surfactant free gold nanoparticles as additivesE. Stratakis 1 , G. D. Spyropoulos1 and E. Kymakis2

1 Institute of Electronic Structure and Laser (IESL), Foundation for Research and Technology-Hellas (FORTH), Heraklion, Greece and Dept. of Materials Science and Technology, University of Crete, Heraklion, Greece.2 Center of Materials Technology and Photonics & Electrical Engineering Department, Technological Educational Institute (TEI) of Crete, Heraklion, Greece

10:20 Current Analytical Strategies for Detecting Trace Amounts of Nanoparticles in the EnvironmentS.A. Pergantis, E.A. KapelliosEnvironmental Chemical Processes Laboratory, Department of Chemistry, University of Crete


11:20 Dopant segregation in silicon nanoparticlesAlexandra Carvalho1, Mark J. Rayson 2, Sven Öberg 2, Patrick R. Briddon 3

1 Department of Physics, I3N, University of Aveiro, Aveiro, Portugal 2 Department of Engineering Sciences and Mathematics, Luleå University of Technology, Luleå, Sweden 3 School of Electrical, Electronic and Computer Engineering, University of Newcastle upon Tyne, Newcastle upon Tyne, United Kingdom

11:50 Diamond nanoparticles in amorphous matricesGeorge KopidakisDepartment of Materials Science and Technology, University of Crete

12:10 Discussion

13:00Lunch

Session IV: Nanoparticle spectroscopy Chair: K. Velonia

14:30 Biomacromolecule Mediated Ag@Au Core-Shell Nanoparticles and their Performance as SERS LabelsMustafa Çulha, Burak Çağlayan, Ali Yasin Sonay and Mehmet KahramanYeditepe University, Turkey



15:00 Control of optical resonances and the near field around metallic nanoparticlesB. Hourahine, F. PapoffDepartment of Physics, SUPA, University of Strathclyde, UK


16:00 Multi-scale modelling of hybrid molecule/metal nanostructuresK. Jhonston2, T. Rissanou1, V. Harmandaris1,2

1 Department of Applied Mathematics, University of Crete 2 Max Planck Institute for Polymer Research, Mainz, Germany

16:20 Spectroscopic signature of gold nanoparticles: a multi-scale simulationGeorgios Barmparis, George Kopidakis and Ioannis RemediakisDepartment of Materials Science and Technology, University of Crete

16:40Discussion

20:30Dinner

Wednesday, 03/10/2012

9:30Open discussion

10:30Posters

11:30Closing remarks



Threedimensional characterization of nanoparticles by electron tomography

M.D. Rossell*, R. Erni Electron Microscopy Center, EMPA, Swiss Federal Laboratories for Materials

Science & Technology, Dübendorf, Switzerland

S. Van Aert, G. Van Tendeloo Electron Microscopy for Materials Research, EMAT, University of Antwerp,

Antwerp, Belgium

K.J. Batenburg IBBTVision Lab, University of Antwerp, Wilrijk, Belgium

Electron tomography has emerged as a powerful technique to address fundamental questions in materials science. At present, the spatial resolution of conventional electron tomography reaches 1 nm3 and a large number of images (<100) are required to compute̴ accurate reconstructions. As an example, the detailed structure of LiFePO4 nanoparticles will be shown [1]. Recently, we have demonstrated a comprehensive approach for 3D atomic imaging. The approach utilizes a combination of highresolution scanning transmission electron microscopy, atom counting using a thorough modelbased statistical analysis and 3D reconstruction by applying discrete tomography from only two projected images. This is demonstrated using nanosized Ag clusters embedded in an Al matrix [2]. This new technique reveals great potential for various applications regarding the atomic characterization of all kinds of complex nanometrescale structured materials, particularly nanoparticles and nanocavities.

Figure 1: Computed 3D reconstruction of an Ag nanocluster viewed along

three different directions.

References [1] D. Carriazo, M.D. Rossell, G. Zeng, I. Bileka, R. Erni & M. Niederberger, Small 8, 2231 (2012). [2] S. Van Aert, K.J. Batenburg, M.D. Rossell, R. Erni & G. Van Tendeloo, Nature 470, 374 (2011). [email protected]


Notes



Nanoparticles studied by Xray microscopy with high spatial and spectral resolution

P. Guttmann*, K. Henzler, S. Werner, S. Rehbein, G. SchneiderHelmholtzZentrum Berlin für Materialen und Energie GmbH, Institute for Soft Matter and Functional

Materials, AlbertEinsteinStr. 15, 12489 Berlin, Germany

The fullfield transmission Xray microscope (TXM) operating at the undulator beamline U41SGM at the electron storage ring BESSY II of HelmholtzZentrum Berlin (HZB) combines high spectral and spatial resolution [1]. The spectral resolution E/∆E is as high as 104 and the spatial resolution in 2D can reach up to 11 nm (halfpitch) [2]. Investigation of nanoparticles in the volume of e.g. cells can be done with a 3D resolution of 36 nm (halfpitch) [3]. As the field of view is in the range of 1520 µm one image stack already visualize a large number of nanoparticles and contains therefore statistical information. We present examples of near edge Xray absorption spectroscopy (NEXAFS) studies of different nanoparticles like TiO2 and Fe performed with the HZB TXM. Nanoscale tomography studies of nanoparticles in cells and their behavior as well as interactions with cells will be shown. This paves the way for a better understanding of the toxicologic effect of these nanoparticles on cells and can be helpful for the development of drugs delivered by nanoparticles into cells.

References

[1] Guttmann P et al., Nature Photonics 6 (2012), 2529 [2] Rehbein S et al., Optics Express 20 (2012), 58305839[3] Schneider G et al., Nature Methods 7 (2010), 985987

* peter.guttmann@helmholtzberlin.de


Notes



SamariumCNT interaction: HEXPS and HTEM

A. A. El Mel, P. De Marco, R. Snyders and C. BittencourtChiPS – University of Mons – Belgium

J. GhijsenLISE University of Namur Belgium

S. Thiess, W. DrubeDeutschen Elektronen Synchrotron DESY, D22603 Hamburg, Germany

X. Ke, G. Van TendelooEMAT –University of Antwerp – Belgium

Reports have demonstrated that the metal CNT interaction is one of the key issues allowing the fabrication of highly efficient CNTbased devices. The choice of metal is established according to the application aimed for. In particular, lanthanides exhibit a wide variety of physical properties that can be tuned by inducing small changes in their electronic structure. Among the studied lanthanides, Sm is of particular interest owing to its potential application in photonics, in microelectronic industry and in catalysis. From a fundamental point of view, the interest arises in the two different isoenergetic states that may coexist: due to the gain in cohesive energy, Sm, which has a divalent 4f6(sd)2 configuration in the free atomic, hybridizes into a trivalent 4f5(sd)3 state in the bulk metal. However, the less coordinated Sm atoms at the surface – their cohesive energy is smaller are divalent. Previous studies of Samarium overlayers on various substrates have concluded that Sm may be divalent, trivalent, or homogeneously mixed valent in interfaces. The nature of the mixed valence, i.e., if it is heterogeneous (different valence at different sites) or homogeneous (noninteger valence at a given site), may be determined by analysing the photoelectron peak generated by the photoelectrons emitted from atoms at the surface.

Here, pristine CNT and oxygen functionalized with different amount of Sm, were studied. Transmission electron microscopy showed the formation of Sm nanoparticles at the CNT surface (fig.1). The SmCNT interaction was investigated by photoelectron spectroscopy performed at the Xray wiggler beamline BW2 of DORIS III (DESY, Hamburg) using a photon energy of 3.5 keV. It is demonstrated the charge transfer from Sm atoms to the first layers of MWCNTs. This charge transfer induces a rigid band shift of all electronic states and an increase in the asymmetry of the C1s peak, i.e., in the metallic character of the CNT. The presence of the oxygen at the interface hampers the charge transfer. The Sm atoms are in the trivalent state. The effect of the evaporation of gold on the Sm/CNTs will be discussed based on the observation of the reduction of the C 1s intrinsic asymmetry.

Figure 1: Highresolution TEM micrograph of pristine MWCNT decorated with Sm nanoparticles. The nominal evaporated amount of Sm was 5 Å.


Notes



Synthesis of Nanocatalysts within pHresponsive Polymeric Nanostructures

S. H. Anastasiadis1,2,* M. Kaliva,1,3 K. Chistodoulakis,1,3 M.A. Frysali,1,2, L. Papoutsakis1 and M. Vambakaki1,3

1 Institute of Electronic Structure and Laser, Foundation for Research and TechnologyHellas, P.O. Box 1527, 711 10 Heraklion Crete, Greece

2 Department of Chemistry, University of Crete, 710 03 Heraklion Crete, Greece3 Department of Materials Science & Technology, University of Crete, 710 03 Heraklion Crete, Greece

Electrostatically and sterically stabilized polymer microgel particles have been synthesized containing either amino (poly(2(diethylamino)ethyl methacrylate), PDEA) or carboxylic acid (poly(acrylic acid), PAA; poly(methacrylic acid), PMAA) functional groups. The pHresponsive PDEA, PAA and PMAA particles are used as nanoreactors for the synthesis of a large variety of metal nanoparticulate catalysts due to their functional amine and carboxylic acid groups; Pt, Pd, Ru and Ni nanoparticles have been synthesized [1,2]. Between the two polyacid systems, the more polar PAA microgels were designed as the nanocatalyst carrier system in aqueous reaction media while the less polar PMAA particles were prepared as the metal nanoparticle template for use in catalytic reactions that take place in organic solvents. The sterically and electrostatically stabilized microgel particles possess surface functional groups that can potentially interact with the microchannel walls of microfluidic catalytic reactors. Acknowledgements: Part of this research was sponsored by the European Union (POLYCAT; grant agreement CPIP 2460952).

Figure 1: Schematic representation of the nanoparticle synthesis within a microgel

References

[1] D. Palioura, S. P. Armes, S. H. Anastasiadis and M. Vamvakaki, Langmuir 23, 57615768 (2007)

[2] E. Pavlopoulou, G. Portale, K. E. Christodoulakis, M. Vamvakaki, W. Bras and S. H. Anastasiadis, Macromolecules 43, 98289836 (2010).

* [email protected]


Metal precursor

incorporation

Reduction

mailto:[email protected]

Notes



Gold nanostructures: challenges and opportunities of wet synthesis

N. Lopez*, G. NovellLeruthInstitute of Chemical Research of Catalonia, ICIQ, Avgda. Països Catalans, 16, 43007

Tarragona, Spain

Gold nanoparticles can be synthetized with a myriad structures ranging from octahedral objects to nanorods. By means of Density Functional Theory we have analyzed the role of the different steps in the synthesis and the synergetic effects of different ingredients in the wet synthesis.

Figure 1: Gold nanostructure representing a rod.

References

[1] G. NovellLeruth, N. Lopez in preparation

* [email protected]


Notes



Hydrodechlorination of trichloroethylene over Pdbased nanostructures

K. Honkala∗ J. Andersin Department of Chemistry, Nanoscience Center, P.O.Box 35

40014 University of Jyväskylä, Finland

Understanding the catalytic conversion of organic molecules is pivotal for accessing the overall picture of numerous industrially and environmentally important reactions. If one can selectively make or break a chosen bond, it will increase gains of wanted product molecules and reduce unwanted, often harmful, side products or waste. Density functional theory calculations are nowadays routinely employed to calculate adsorption and activation energies over catalytic materials. In this presentation I will discuss our recent density functional theory studies on the conversion of simple hydrocarbons over transition metal surfaces and nanostructures. In particular, I will focus on the hydrodechlorination of trichloroethene over Pdbased materials. Experimentally, Pd covered Au nanoparticles have been found to be more efficient in converting trichloroethene to ethane than pure Pd. The precise structure of these nanoparticles is not known. We performed density functional theory calculations [1] to explore possible structures. Our results show that trichloroethene adsorption is endothermic over Au, almost thermoneutral on PdAu alloy, and exothermic on Pd overlayer structures on Au [2]. The variation of adsorption energy can be tentatively assigned to be due to the ligand and coordination effects. Our results show that in all cases CCl bond breakings take place more readily than CH bond formations, and that TCE dechlorinates fully producing CCH precursors for the hydrogenations. The reaction pathway through radicallike species provides a possible explanation to the experimental product distributions that show a nominal amount of lesser chlorinated species in the presence of excess hydrogen [3].

Figure 1: The calculated hydrodechlorination pathway for trichloroethylene over Pd.

References [1] J.Enkovaara et al. J. Phys.: Condens. Matter 22 253202 (2010). [2] J. Andersin and K. Honkala PCCP 13 1386 (2011). [3] J. Andersin. P. Parkkinen and K. Honkala J. Catal.290 118 (2012).

_____________________________________

∗[email protected]


Notes



Customised transition metal oxide nanoparticles for the controlled production of carbon nanostructures

Frank Dillon, Karl Mandel, Anakha Ajayan, Antal Koos, Nicole Grobert

Department of Materials, Parks Road, University of Oxford, Oxford, OX1 3PH [email protected]

Nanoparticles play an extremely important role in the growth of carbon nanotubes. The diameter, chirality and structure of the nanotubes are thought to be dictated by the nanoparticle when the tubes are formed via chemical vapour deposition (CVD) techniques. This work describes the wet chemical synthesis of monodisperse transition metal nanoparticles of controlled size and the growth of carbon nanotubes from these particles using a CVD reactor. Monodisperse magnetite (Fe3O4) 1, cobaltous oxide (CoO) 1 and amorphous nickel phosphide (NiP) 2 nanoparticles were synthesised using a fast (up to 50 times quicker than previously reported) and facile onepot, onestep reaction. The Fe3O4 nanoparticles had a constant size between 5 to 7 nm independent of the reagents used. Size controlled cube shaped CoO particles in the range of 10–20 nm were formed and it was possible to create voids in these particles in a controlled way. The NiP nanoparticles were amorphous, contained ~ 30 at% P and their size was controlled between 7–21 nm. Carbon nanotubes were grown on these catalyst particles and their structures were compared. Structures of the nanotubes differed between straight, bamboolike or partly coiled depending on the nanoparticle system used, suggesting the possibility of selection of these structures.

TEM images of magnetite, cobaltoxide and nickelphosphide (from left to right).

1. K. Mandel, F. Dillon, A. A. Koos, Z. Aslam, F. Cullen, A. Crossley, H. Bishop, N. Grobert. RSC Adv. 2, 37483752 (2012).

2. K. Mandel, F. Dillon, A. A. Koos, Z. Aslam, K. Jurkschat, F. Cullen, A. Crossley, H. Bishop, K. Moh, C. Cavelius, E. Arzt, N. Grobert. Chem. Commun. 47, 4108–4110 (2011).



Notes



Catalysis of novel organic transformations by supported gold nanoparticles

Manolis Stratakis Department of Chemistry, University of Crete, 71003 Iraklion, Greece

Apart from being superb catalysts in aerobic oxidative processes,1 supported gold nanoparticles (Au NPs) have recently found to exhibit novel and unprecedented catalytic properties to a variety of other organic transformations.2 We will present the recent achievements in catalysis by gold nanoparticles supported on TiO2 from our research group in epoxide,3 alkyne,4 silane,5 and borohydride activation.

Figure 1: Recent examples of organic transformations catalyzed by Au/TiO2 from our group.

References [1] Zhang, Y.; Cui, X.; Shi, F.; Deng, Y. Chem. Rev. 2012, 112, 2467. [2] Stratakis, M.; Garcia, H. Chem. Rev. 2012, 112, 4469. [3] Raptis, C.; Garcia, H.; Stratakis, M. Angew. Chem., Int. Ed. 2009, 48, 3133. [4] a) Efe, C.; Lykakis, I. N.; Stratakis, M. Chem. Commun. 2011, 47, 803. b) Gryparis, C.; Efe, C.; Raptis, C.; Lykakis, I. N.; Stratakis, M. Org. Lett. 2012, 14, 2956. [5] a) Lykakis, I. N.; Psyllaki, A.; Stratakis, M. J. Am. Chem. Soc. 2011, 133, 10426. b) Psyllaki, A.; Lykakis, I. N.; Stratakis, M. Tetrahedron 2012, 68, in press. c) Gryparis, C.; Stratakis, M. Submitted to Chem. Commun. 2012.


Notes



Structural Phase Transitions in FePt Nanoparticles: Chemical & Magnetic Consequences

L. Han, U. Wiedwald, and P. ZiemannInstitute of Solid State Physics, Ulm University, D89081 ULM, FRG

Due to their high magneto crystalline anisotropy (MCA) energy, FePt nanoparticles (NP) in the face centered tetragonal (fct) phase promise to overcome the super paramagnetic limit even at room temperature for particles as small as 3 nm. In that case FePt NPs could play a role in magnetic data storage applications, if additional requirements like their arrangement in highly ordered arrays as well as chemical stability can be accomplished. In the present contribution, the fabrication of hexagonally ordered arrays of FePt NPs will be demonstrated based on two bottomup techniques: Selforganization of precursor loaded micelles or Polystyrene (PS) colloids [1,2]. The narrow size distribution of the resulting NPs allows studying the size dependence of their MCA values as well as of their stability against oxidation.The experimental results indicate systematically lower MCA values for decreasing particle sizes. This decrease is accompanied by a decrease of the magnetic moments as revealed by XMCD. Both observations may be related to Pt surface segregation during the annealing process necessary to obtain the magnetically attractive fct phase.

References

[1] Ulf Wiedwald, Luyang Han, Johannes Biskupek, Ute Kaiser, and Paul Ziemann, Beilstein J. Nanotechnol. 1, 24 (2010).[2] Achim Manzke, Alfred Plettl, Ulf Wiedwald, Luyang Han, Paul Ziemann, Eyk Schreiber, Ulrich Ziener, Nicolas Vogel, Katharina Landfester, Kai Fauth, Johannes Biskupek, Ute Kaiser, Chem. Mater. 24, 1048 (2012).


Notes



Enhanced performance in organic photovoltaic cells using surfactant free gold nanoparticles as additives

E. Stratakis, G. D. SpyropoulosInstitute of Electronic Structure and Laser (IESL), Foundation for Research and TechnologyHellas (FORTH), Heraklion 711 10, Greece and Dept. of Materials Science and Technology, University of

Crete, Heraklion 714 09, Greece.

E. KymakisCenter of Materials Technology and Photonics & Electrical Engineering Department,

Technological Educational Institute (TEI) of Crete, Heraklion 71003, Greece

Metallic nanoparticles formed by ablation in liquids with pico and femtosecond laser pulses are attractive candidates as additives in the active layer of OPV devices. Such NPs are free of surfactants and passivation layers that are inevitably present on the surface of the chemically synthesized NPs. In this work, surfactant free Au NPs with various concentrations are embedded in the poly(3 hexylthiophene) (P3HT):phenyl C61 butyric‐ ‐ ‐ acid methyl ester (PCBM) active layer of OPV devices for enhanced device performance. An improvement in power conversion efficiency by 40% compared to the pristine device without NPs, was achieved. Notable, the spectral ranges of both the enhanced light absorption and quantum efficiency comply with the individual LSPR region of the Au NPs used. The efficiency is postulated to be enhanced by exploiting increased absorption around the small diameter NPs integrated into the active layer as well as strong light scattering from the large diameter NPs and clusters, both effects stemming from the excitation of the LSP waves at the NP/photoactive layer interface. Moreover, it was recently demonstrated by our group that the incorporation of NPs in the photoactive layer does not only lead to an increase in the performance but gives rise to enhanced structural stability of the blend. Therefore, the performance enhancement can be also attributed to the improvement of the photoactive layer morphology due to the presence of NPs.

Figure 1: CurrentVoltage characteristics of laser synthesized, surfactant free, Au nanoparticles doped organic photovoltaic cells


Notes



Current Analytical Strategies for Detecting Trace Amounts of Nanoparticles in the Environment

S.A. Pergantis*, E.A. KapelliosEnvironmental Chemical Processes Laboratory, Department of Chemistry, University of Crete,

Voutes Campus, Heraklion 71003, Crete, Greece

The continuous development of an increasing number of engineered nanoparticles (ENP), with unique optical, electrical and chemical properties, for the purpose of incorporating them into a wide range of industrial, medical and agricultural products, is a strong indicator for their increased introduction into the environment. Such an eventuality is now causing alarm, both to public and scientists, mainly because of the potential impact of ENP on the environment, ecosystems and human health. In fact, the US Environmental Protection Agency (EPA) has highlighted this as a major research priority in their “Nanomaterial Research Strategy”report.[1] In this report the importance of developing analytical methods for the determination of nanomaterials in environmental and biological matrices has been clearly stated and highlighted as Key Scientific Question no. 1.

In this presentation we will describe our recent efforts on the development of advanced analytical techniques for detecting ultratrace amounts of metalcontaining ENP in complex environmental matrices. More specifically, the development and use of single particle (SP) detection of NP using inductively coupled plasma mass spectrometry (ICPMS), with and without a separation technique, will be discussed.[23] Apart from its extremely high sensitivity and selectivity the SPICPMS approach also offers tremendous potential for rapid screening of environmental samples, with minimum sample preparation requirements. The use of separation techniques such as hydrodynamic liquid chromatography and ion mobility spectrometry in combination with SPICPMS will also be presented.

References

[1] U.S. Environmental Protection Agency, Office of Research and Development, “Nanomaterial Research Strategy”. EPA 620/K09/011, 2009.[2] S. A. Pergantis, T. L. JonesLepp, E. M. Heithmar, Anal. Chem. 84 (15), 6454 (2012).[3] E. A. Kapellios and S. A. Pergantis, J. Anal. At. Spectrom. 27, 21, (2012).

* [email protected]


Notes



Dopant segregation in silicon nanoparticles

Alexandra Carvalho∗ Department of Physics, I3N, University of Aveiro, Aveiro, Portugal

Mark J. Rayson, Sven Öberg Department of Engineering Sciences and Mathematics,

Luleå University of Technology, Luleå Sweden

Patrick R. Briddon School of Electrical, Electronic and Computer Engineering,

University of Newcastle upon Tyne, Newcastle upon Tyne, United Kingdom

Silicon nanoparticles can be doped ntype or ptype using phosphorus and boron, respectively [1,2]. However, the doping of nanoparticles suffers from difficulties not present in the bulk material, such as quantum confinement, screening by image charges and segregation. We have used firstprinciples calculations to understand how the energetics of groupIII and groupV dopants in silicon nanocrystals is changed by surface oxidation. This was done by comparing the radial dependence of the dopant formation energies for silicon nanocrystals with hydride and silanol terminated surface and nanoparticles surrounded by an oxide shell. We show that the oxidation of the surface affects drastically the equilibrium distribution of dopants for donors and for acceptors. In the nanocrystals with hydrideterminated surface, most dopants avoid bonding with oxygen. In SiO2 doped nanocrystals, phosphorus prefers positions in the silicon core.

Figure 1: Formation energy of positively charged substitutional phosphorus in a 1.5 nm diameter nanoparticle covered by a 2 nmthick amorphous SiO2 shell. ∼

References [1] A. R. Stegner et al., Phys. Rev. B 80, 165326 (2009). [2] X. D. Pi et al., Appl. Phys. Lett. 92, 123102 (2008).

_________________ ∗ [email protected]


Notes



Atomistic simulations of nanocrystal/amorphous composite materials

Georgios KopidakisDepartment of Materials Science and Technology, University of Crete

Heraklion, Crete, Greece

Mixed phase nanocrystal/amorphous and nanocrystalline materials exhibit properties which are often substantially different from conventional bulk crystalline, polycrystalline and amorphous solids. We present results of atomistic simulations of systems consisting of nanoparticles in amorphous hosts using empirical and semiempirical models, with particular emphasis on the calculation of structural, mechanical, and optoelectronic properties which connect atomic structure with experiment. The properties of carbonbased nanostructured materials are examined in order to identify spectroscopic signatures and simple characterization methods. A class of interesting systems is diamond nanoparticles (nD) embedded in amorphous carbon (aC) matrices. In this case, optoelectronic properties are dominated by aC and the presence of nD cannot be experimentally inferred solely from them [1,2]. However, molecular dynamics simulations point to some distinct features of the vibrational spectra of nD/aC which could be observed in experiments. The dependence of mechanical properties on the size of the nanocrystals in the mixed phase is also addressed. Ultrananocrystalline diamond (UNCD), consisting of nD grains separated by thin aC boundaries, is of particular interest in this context. We find a universal scaling law for mechanical properties as a function of average grain size which applies to very different materials, such as UNCD and nanocrystalline metals, and which is explained by simple theoretical arguments [3,4]. Some other aspects of computational approaches which are complementary to experiments for the detection and characterization of nanoparticles in solids are discussed.

nD/aC [1] UNCD [3] nanocrystalline Cu [4]

A. G. Kopidakis, I.N. Remediakis, M.G. Fyta, and P.C. Kelires, “Atomic and Electronic Structure of CrystallineAmorphous Carbon Interfaces”, Diamond and Related Materials, 16, 1875 (2007).

B. G. Vantarakis, C. Mathioudakis, G. Kopidakis, C.Z. Wang, K.M. Ho, and P.C. Kelires, “Interfacial Disorder and Optoelectronic Properties of Diamond Nanocrystals”, Phys. Rev. B, 80, 045307 (2009).

C. I.N. Remediakis, G. Kopidakis, and P.C. Kelires, “Softening of UltraNanocrystalline Diamond at Low Grain Sizes”, Acta Materialia, 56, 5340 (2008).

D. N.V. Galanis, I.N. Remediakis, and G. Kopidakis, “Mechanical Response of Nanocrystalline Cu from Atomistic Simulations”, Phys. Status Solidi C, 7, 1372 (2010).


Notes



Biomacromolecule Mediated Ag@Au CoreShell Nanoparticles and their Performance as SERS Labels

Mustafa Çulha, Burak Ça layan, Ali Yasin Sonay and Mehmet Kahramanğ

The bimetallic coreshell noparticles are unique nanostructures with their tunable plasmonic properties and they can be used in a range of applications from sensing, biomedical and cellular imaging, to construction of novel photonic devices. Previously reported structures are either alloys or bimetallic structures composed of Ag and Au metals. However, novel approaches are necessary to fully benefit from their unique plasmonic properties. In order to generate novel structures, we employ biomacromolecules such as oligonucleotides, peptides and carbohydrates to functionalize AuNPs along with a Raman active molecule before coating with Ag or Au metallic shell. The presence of chemically attached biomacromolecules serves as not only generating nanometer size gaps around the Raman active molecules but also increases the compatibility of metals with the underlying metal surface. The influence of chemical structure the biomacromolecules on the SERS performance of the nanoparticles systematically was investigated. For example, peptides designed only negatively and positively charged with different lengths were investigated. The other parameters such as shell thickness and core size were also explored for optimal SERS performance. The results show that the synthesized coreshell structures are much more SERS active than Ag and Au alone and they can be used for detection of variety of molecules and perhaps in other types of applications such as biomedical imaging and photothermal therapy as well. We believe that engineering such molecular structures into the nanoparticles may open new venues for the construction of novel plasmonic structures.


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Control of optical resonances and the near field around metallic nanoparticles

B. Hourahine∗ ,F. Papoff Department of Physics, SUPA University of Strathclyde John

Anderson Building 107 Rottenrow Glasgow G4 0NG UK

Optical resonances of nanostructures are normally assumed to be either bright or dark, with a simple correspondence between spectra and resonant features, however this picture can be qualitatively misleading. By using the concept of the principal optical modes[1] of nanoparticles, we demonstrate that it is possible to move, change line shapes or even remove optical resonances entirely in the spectra of metal nanoparticles (Fig. 1). With a modest degree of phase control between two or more different incident sources of light, it also becomes possible to radically change the optical near field around nanoparticles and nanostructures(Fig. 2). This provides control over the location and type of optical hot spots, while also providing a direct farfield indication of what is happening at the nanoscale.

Figure 1: Optical scattering spectra of gold rodshaped particle (480 nm length, 40 nm diameter). The ’natural’ spectra for this structure, when illuminated from the side, shows a Fanolike resonance (redtrace, with asymmetric line shape). By adding an additional field, either the mode which provides most of the scattering intensity, or the dark mode causing this asymmetric resonance is removed (blue and black lines respectively). Spectra over a wider range is shown inset.

Figure 2: Cartoon of the near field of a small gold disc (120 nm diameter, 20 nm thickness). A) Illuminated axially, showing two clear hot spots along the direction of the electric field of the light. B) Illuminated with an additional light source, converting the strong field regions into a ring around the particle.

References [1] F. Papoff and B. Hourahine, Optics Express, 19 21432–21444 (2011) http://dx.doi.org/10.1364/OE.19.021432 .

_________________________________ ∗[email protected]


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Multiscale modelling of hybrid molecule/metal nanostructures

K. Jhonston2, T. Rissanou1, V. Harmandaris1,2,*

1. Department of Applied Mathematics, University of Crete 2. Max Planck Institute for Polymer Research, Mainz, Germany

Hybrid molecule/metal interfaces are encountered in many technologies involving adhesives, coatings, lubricants, and composite materials. In such systems the interaction between the adsorbed molecules and the metal surfaces control the overall performance of the multiphase material system. Here we present a hierarchical multiscale approach that involves different levels of description in order to study complex multiphase nanocomposite systems. Our approach combines quantum calculations as well as microscopic (atomistic) and mesoscopic (coarsegrained) dynamic simulations [13]. Our primary goal is to study the effect of metal confinement on the structural and dynamical properties of liquid systems, for a variety of materials. The consistent combination of different levels of description allows us to quantitatively model hybrid complex liquid/metal systems. As an example we model the benzene/gold and the polystyrene(PS)/gold(Au) systems. In Figure 1 we observe typical snapshot of the molecular simulations of PS/Au interfacial systems [2].

Figure 1: Hierarchcial multiscale simulation of polymer/metal interfacial systems (polystyrene/gold). Snapshots of various films

References [1] Harmandaris, V. et al. Macromolecules, 39, 6708 (2006); 40, 7026 (2007). Soft Matter, 208, 2109 (2009). [2] Johnson K. and Harmandaris, V. J. Phys. Chem. C., 115, 14707 (2011); Soft Matter, 8, 6320 (2012). [3] Rissanou, T. and Harmandaris, V, submitted.

_____________________* [email protected]


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Environmentdependent shape and properties of gold nanoparticles: a first principles study

G. D. Barmparis* and I. N. Remediakis Department of Materials Science and Technology

University of Crete, 71003 Heraclion, Crete, Greece

We perform density functional theory (DFT) simulations to calculate the surface and interface energies of clean and covered gold surfaces, respectively. We then use the results together with the Wulff−Kaishew theorem in order to predict the equilibrium shape of large gold nanoparticles, that are inaccessible by direct atomistic simulations, in various chemical environments. We consider various environments, such as CO gas and alkanethiolates. The interface tension of a metal in equilibrium with a gas is found to depend on the surface tension, the adsorption energy and the coverage of adsorbates. For this reason the investigation of the adsorption energy of the molecules of the environment on gold surfaces is also needed. For gold nanoparticles in inert gas we find (111) faces to dominate the shape at small diameters, followed by (100) ones. For large nanoparticles, other faces with higher Miller indexes may appear. CO oxidation is the most promising application of Aubased catalysts. Interestingly, when Au nanoparticles are exposed to CO gas the equilibrium shape contains a lot more highindex faces, resulting to a more rounded shape. Our observations agree with recent experimental findings. In order to study the shape of gold nanoparticles in alkanethiolate environment, we study the dissociative chemisorption of dimethyl disulfide (CH3 S−SCH3 ) on fourteen different Au(hkl), discussing trends on adsorption energies, bond lengths and bond angles. Methanethiolate (CH3 S−) prefers adsorption on bridge sites on all surfaces considered; hollow and on top sites are highly unfavourable. Gold nanoparticles change their shape upon adsorption of thiolates towards shapes of higher sphericity and higher concentration of stepedge atoms. Finally, we discuss the spectroscopic properties of equilibriumshaped nanoparticles. The energy levels are found to depend not only on the nanoparticle size, but also on the nanoparticle shape. Thus, the electronic density of states can be used as an indirect probe of the size and shape of Au nanoparticles.

__________________________ ∗[email protected]


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POSTERS


Notes

Posters

Shape changes of Au nanoparticles in reactive environment Georgios Barmparis and Ioannis N. RemediakisDepartment of Materials Science and Technology, University of Crete, Heraklion, Crete, GreeceImmobilization of Polymer Microgels Containing Metal Nanocatalysts onto Inorganic SurfacesM.A. Frysali,1,2 M. Kaliva,1,3 L. Papoutsakis,1 M. Vambakaki1,3 and S. H. Anastasiadis1,2

1 Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, Heraklion Crete, Greece2 Department of Chemistry, University of Crete, Heraklion Crete, Greece3 Department of Materials Science & Technology, University of Crete Heraklion Crete, GreeceComputational Study of Carbon – based Nanostructured MaterialsAristea Maniadaki and Georgios KopidakisDepartment of Materials Science and Technology, University of Crete, Heraklion, Crete, GreeceHybrid carbon/metal nanocomposite materialsC. Mathioudakis 1 , P.C. Kelires1, G. Vantarakis2

1Research Unit for Nanostructured Materials Systems, Department of Mechanical and Materials Science Engineering, Cyprus University of Technology, Limassol, Cyprus2Department of Materials Science and Technology, University of Crete, Heraklion, Crete, GreeceTransition metal nanoparticles for hydrogen storageGeorge Psofogiannakis and George FroudakisDepartment of Chemistry, University of Crete, GreeceEffect of Graphene on Polystyrene and Poly(Methyl Methacrylate) Structural and dynamical PropertiesAnastassia N. Rissanou1,2 and Vagelis Harmandaris1,2

1 Department of Applied Mathematics, University of Crete, Heraklion, Crete, Greece. 2Institute of Applied and Computational Mathematics, Foundation for Research and Technology Hellas, Heraklion, Greece. In Situ Hierarchical Formation of Giant Amphiphile Bionanoreactors K. Velonia 1 , E. Daskalaki2

1Department of Materials Science and Technology, University of Crete, Heraklion, Crete, Greece2Department of Chemistry, University of Crete, Heraklion, Crete, Greece



Shape changes of Au nanoparticles in reactiveenvironment

G. D. Barmparis* and I. N. RemediakisDepartment of Materials Science and Technology

University of Crete, 71003 Heraclion, Crete, Greece

Although gold is known to be noble, Au nanoparticles show extreme chemical activity and are widely used in catalysts. Coated Au nanoparticles show unique optical properties and are used in a variety of applications. Properties of Au nanoparticles depend not only on their size, but also on their shape. In the present work, we predict the shape of Au nanoparticles in different environments (inert gas, CO and thiolates) based on firstprinciples simulations. We employ density functional theory (DFT) as implemented in the opensource Dacapo and GPAW packages. We calculate the surface tension of clean and covered Au(hkl) surfaces with h, k, l < 4 and use the results together with Wulff’s theorem to predict equilibrium shapes. For nanoparticles in inert gas atmosphere, we found two different shapes: truncated octahedra for sizes up to about 16 nm and more complicated ones containing five faces for larger particles. CO gas favours almost spherical particles. Thiolatecovered nanoparticles have surprisingly symmetric shapes. This work was supported by IESL/FORTH, a HPCEUROPA2 project (project number: hpce3116) with the support of the European Commission Capacities Area Research Infrastructures Initiative, COST action MP0901 (NanoTP) and the University of Crete.

_________________________*[email protected]


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Immobilization of Polymer Microgels Containing Metal Nanocatalysts onto Inorganic Surfaces

M.A. Frysali,1,2* M. Kaliva,1,3 L. Papoutsakis,1 M. Vambakaki1,3 and S. H. Anastasiadis1,2

1 Institute of Electronic Structure and Laser, Foundation for Research and TechnologyHellas, P.O. Box 1527, 711 10 Heraklion Crete, Greece

2 Department of Chemistry, University of Crete, 710 03 Heraklion Crete, Greece3 Department of Materials Science & Technology, University of Crete, Heraklion Crete, Greece

This study is concerned with the attachment of electrostatically and sterically stabilized polymer microgel particles based on poly(acrylic acid), PAA, and poly(methacrylic acid), PMAA, onto inorganic surfaces. The microgels were prepared by emulsion radical polymerization [1] and characterized by dynamic light scattering (DLS) and scanning electron microscopy (SEM), which verified their spherical shape and uniform size distribution. These microgels are utilized as nanoreactors for the synthesis of metal nanoparticles to be utilized as nanocatalysts; the nanoparticles were characterized by Transmission Electron Microscopy (TEM). The attachment of the microgel particles onto the various surfaces, which can potentially be used as the walls of microfluidic reactors, was investigated by SEM and Atomic Force Microscopy (AFM) [2]; glass, silicon and alumina were used as substrates. The durability of the microgel particles attached onto the surfaces against hydration and flow forces was tested utilizing repeated immersion of the surfaces into water undergoing mechanicallygenerated hydrodynamic flow. Acknowledgements: Part of this research was sponsored by the European Union (POLYCAT; grant agreement CPIP 2460952).

Figure 1: SEM of PAA nanoparticles

References

[1] D. Palioura, S. P. Armes, S. H. Anastasiadis and M. Vamvakaki, Langmuir 23, 57615768 (2007).[2] H. Chen, L. Hu, X. Fang and L. Wu, Adv. Funct. Mater. 22, 12291235 (2012).

* [email protected]



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Computational study of carbonbased nanostructured materials

Aristea E. Maniadaki and Georgios KopidakisDepartment of Materials Science and Technology, University of Crete, Heraklion, Crete, Greece

Modern methods in materials synthesis take advantage of the ability of carbon atoms to form bonds with different hybridizations and result in a variety of allotropic forms of carbon. Carbonbased nanostructures exhibit fundamental interest and have promising applications. Among these nanostructures, the mixed phase of amorphous carbon (aC) and diamond nanoparticles (nD) has been less characterized, with many of its properties remaining unexplored. We perform atomistic simulations with empirical potentials in order to create several samples of aC/nD nanocomposites with different nD sizes and aC densities. We analyze the structure, stability, and mechanical properties of these nanocomposite materials and our results compare well with experiment and previous simulations. Furthermore, we study their dynamical properties to find that some pronounced features of their vibrational spectra may be observed in experiments.


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Hybrid carbon/metal nanocomposite materials

C. Mathioudakis*, P.C. KeliresResearch Unit for Nanostructured Materials Systems, Department of Mechanical and Materials Science Engineering, Cyprus University of Technology, P.O. Box 50329, 3603 Limassol, Cyprus

G. VantarakisDepartment of Materials Science and Technology, University of Crete, P.O. Box 2208, 710 03

Heraklion, Crete, Greece

We study hybrid carbon/metal nanocomposite materials. These multimaterials consist of Diamondlike Carbon (DLC) matrices with inculsions of metals (e.g. Ti). The produced nanostructured and nanocomposite thin films can be used as protective coatings and solid lubricants. In addition, new nanostructured selective coatings can be applied in solar thermal energy devices.

The physical properties of DLC change by the insertion of metal nanoparticles. We calculate the elastic properties as a function of the structural parameters and show their variation. In order to study large systems, we use the semiempirical Modified Embedded Atom Method (MEAM). Our calculations on the mechanical response of DLC/metal nanocomposites agree well with ab initio results, carried out using Density Functional Theory (DFT).

* [email protected]



Notes



Transition metal nanoparticles for hydrogen storage

George Psofogiannakis and George FroudakisDepartment of Chemistry, University of Crete. Greece

It has been observed in several experiments that the hydrogen storage capacity of high surface area sorbents (graphitic carbons, nanotubes, MetalOrganic Frameworks) is enhanced when small quantities of transition metal nanoparticles are doped in the material. The drastic change of the H2 adsorption profile is often attributed to the alleged “spillover” mechanism. Based on this, hydrogen is bound in atomic form within the material. The role of the metal nanoparticles consists of catalyzing the process by dissociating the H2 molecules and mediating the transport of H atoms to the sorbent.

We have computationally studied, via Density Functional Theory, the thermodynamics and kinetics of elementary steps of the spillover process and identified the plausibility and of the mechanism and the effect of the surface chemistry of the sorbent, including the role of the metal nanoparticles, and the role of surface chemical functional groups and defects. Based on the results, new sorbents for enhanced hydrogen storage capacity have been proposed. Furthermore, we propose ways of chemical functionalization of graphitic carbon materials that can assist drastically the spillover process.


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EFFECT OF GRAPHENE ON POLYSTYRENE AND POLY(METHYL METHACRYLATE)

STRUCTURAL AND DYNAMICAL PROPERTIES

Anastassia N. Rissanou1,2 and Vagelis Harmandaris1,2 1 Department of Applied Mathematics, University of Crete, GR 71409, Heraklion, Crete, Greece. 2Institute of Applied and Computational Mathematics, Foundation for Research and Technology

Hellas, GR700 13 Heraklion, Greece. Email: [email protected]

Graphene nanocomposites have remarkable physical properties with important applications in many different areas. Here we present a hierarchical simulation methodology in order to study complex multiphase graphene based polymer nanocomposite systems. Our primary goal is to study the effect of the graphene layers on the structural and dynamical properties of polymer systems. In more detail, we study hybrid polymer/graphene interfacial systems (here polystyrene/graphene and poly(methyl methacrylate)/graphene) through a multiscale modeling approach that consists of two stages: In the first one we perform detailed atomistic molecular dynamics (MD) simulations of polymer chains confined between two parallel graphene layers (1). Various properties are being studied related to: (a) Density profile: The timeaveraged molecular density profiles, (z), as a function of the distanceρ from the metal surfaces (zdirection) of the model films are calculated. (b) Structural characteristics: Molecular orientation tendencies induced by the confinement are being studied by calculating the second rank order parameter and the polymer chain’s conformation tensor. (c) Mobility aspects: We study the dynamics of polymer chains, both in the level of the monomer and the chain centerofmass, by monitoring the evolution of the mean square displacements as well as through time autocorrelation functions of a vector along the molecule. All above properties are examined, as a function of the distance from the substrate for a series of film widths, ranging from [2.8514] nm. Finally, the properties of the macromolecular chains are being compared to the properties of the corresponding bulk systems at the same temperature. The second stage of our work involves the extension of the proposed methodology to mesoscopic description using proper coarsegrained (CG) models. To achieve this, a methodology to develop CG models from the atomistic description, proper for bulk polymeric systems, will be extended to hybrid nanocomposite mater (2). This approach allows us to extend simulations in much longer systems and for much longer times. Recently this approach has been combined with abinitio density functional theory calculations in order to derive accurate classical force fields for the molecule/surface interaction from first principles (3).

References

1. Harmandaris, V., Daoulas, K., Mavrantzas, V., “Detailed Atomistic Simulation of a Polymer Melt/Solid Interface: Structure, Density, and Conformation of a Thin Film of Polyethylene Melt Adsorbed on Graphite”, Macromolecules, 38, 5780, (2005).

2. Harmandaris, V. et al., “Hierarchical Modeling of Polystyrene: From Atomistic to CoarseGrained Simulations”, Macromolecules, 39, 6708 (2006); 40, 7026 (2007). Soft Matter, 208, 2109 (2009).

3. Johnson K. and Harmandaris, V. J. Phys. Chem. C., 115, 14707 (2011); submitted.


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In Situ Hierarchical Formation of Giant Amphiphile Bionanoreactors

K. Velonia*, Department of Materials Science and Technology, University of Crete, Heraklion, Crete, Greece

E. DaskalakiDepartment of Chemistry, University of Crete, Heraklion, Crete, Greece

Amphiphilic proteinpolymer chimeras –Giant Amphiphiles are designed to mimic the hierarchical selfassembly displayed in biological and synthetic material systems over a range of lengths. During the last years we synthesized several such proteinpolymer amphiphilic bioconjugates using different synthetic approaches varying from the direct coupling of endfunctionalized polymers to proteins, to the grafting of polymers from protein macroinitiators.[1,2,3] Interestingly, Giant Amphiphiles have shown to assemble into welldefined, functional superstructures suitable for a variety of materials applications. Two different synthetic approaches, the Atom Transfer Radical Polymerization (ATRP) [2] and the Ring Opening Polymerization (ROP) [3] grafting of a series of monomers from protein biomacroinitiators will be comparatively presented (Figure 1). It will be shown that these methods drastically improve synthetic yields and allow studying of the selfassembling behaviour and functionality of Giant Amphiphiles in unprecedented detail. More importantly the “grafting from” in situ, formation of multifunctional nanoreactors with interesting catalytic properties and the synthesis of a novel series of biocompatible and degradable giant soaps will be presented.

Figure 1: General scheme for the hierarchical formation of Bionanoreactors

References

[1] Velonia, Rowan and Nolte J. Am. Chem. Soc. 124, 4224 (2002); Le Droumaguet, Mantovani, Haddleton and Velonia J. Mater. Chem. 17, 1916 (2007). [2] Le Droumaguet and Velonia, K. Angew. K. Chem., Int. Ed. 47, 6263 (2008); Daskalaki, Le Droumaguet, Gérard and Velonia, Chem. Commun. 48, 1586 (2012).[3] Daskalaki, Liamas, Al Tabchi, Dacros and Velonia K. Submitted.

* [email protected]


Notes



Participant ListName Email Country Page

Anastasiadis Spiros H. [email protected] Greece 14

Barmparis Georgios [email protected] Greece 40,44

Bittencourt Carla [email protected] Belgium 12

Carvalho Alexandra [email protected] Portugal 30

Culha Mustafa [email protected] Turkey 34

Daskalaki Eleftheria [email protected] Greece 56

Davelou Daphne [email protected] Greece

Dillon Frank [email protected] United Kingdom 20

Frysali Melina A. [email protected] Greece 46

Guttmann Peter peter.guttmann@helmholtzberlin.de Germany 10

Harmandaris Vagelis [email protected] Greece 38

Honkala Karolina [email protected] Finland 18

Hourahine Ben [email protected] United Kingdom 36

Kopidakis Georgios [email protected] Greece 32

Kotsopoulou Giota [email protected] Greece

Koutsouroumpi Eirini [email protected] Greece

Lopez Nuria [email protected] Spain 16

Maniadaki Aristea [email protected] Greece 48

Markoulaki Vasiliki [email protected] Greece

Mathioudakis Christos [email protected] Cyprus 50

Melissinake Vasileia [email protected] Greece

Pergantis Spiros [email protected] Greece 28

Procaccia Itamar [email protected] Israel

Psofogiannakis George [email protected] Greece 52

Remediakis Ioannis [email protected] Greece

Rissanou Anastasia [email protected] Greece 54

Rossell Marta [email protected] Switzerland 8

Stamatiadis Stamatis [email protected] Greece

Stratakis Emmanouel [email protected] Greece 26

Stratakis Manolis [email protected] Greece 22

Vantarakis Georgios [email protected] Greece

Velonia Kelly [email protected] Greece 56

Whelan Caroline [email protected] Belgium

Ziemann Paul Paul.ziemann@uniulm.de Germany 24




































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