Poster abstracts submitted before deadline for Carbonhagen 2015 can be found below...
In addition we accept post-deadline posters - write name, affilation, title and abstract to abstract@carbonhagen.com and request for a spot.
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posted 28 Jul 2015, 05:12 by info admin
Jaime E. Santos 1, M. I. Vasilevskiy 2, N. M. R. Peres 2, G. Smirnov 2, Yu. V. Bludov 2
1- DTU Nanotech, Building 345B, Ørsteds Pl., 2800 Kongens Lyngby, Denmark 2- Centro de Fisica e Departamento de Fisica, Universidade do Minho, 4710-057 Braga, Portugal
We study the electromagnetic
properties of a metamaterial consisting of polarisable (nano)-particles and a single
graphene sheet placed at the interface between two dielectrics. We show that the
particle's polarisability is renormalised because of the electromagnetic
coupling to surface plasmons supported by graphene, which results in a
dispersive behavior, different for the polarisability components corresponding
to the induced dipole moment, parallel and perpendicular to the graphene sheet.
In particular, this effect is predicted to take place for a metallic particle
whose bare polarisability in the terahertz (THz) region is practically equal to
the cube of its radius (times 4πε0). This opens the possibility to
excite surface plasmons in graphene and enhance its absorption in the THz range
by simply using a monolayer of metallic particles randomly deposited on top of
it, as we show by explicit calculations [1]. [1] Jaime E. Santos, M. I.
Vasilevskiy, N. M. R. Peres, G. Smirnov, Yu. V. Bludov, Phys. Rev. B 90, 235420
(2014)
Jaime E. Santos received his degree
in Physics from the University of Porto, Portugal, in 1993 and his DPhil in
Theoretical Physics from the University of Oxford, in the UK, in 1997. Since
then, he has held positions at the TUM in Munich, at the Hahn Meitner Institute
in Berlin, and at the Universities of Porto and Minho in Portugal. Currently,
he is a Guest Scientist at the CNG, DTU Nanotech, holding a position as
Temporary Associate Professor (Lektor). His main interest is the Physics of
Graphene and related two-dimensional materials, in particular the transport
properties and the optical properties of such systems, but he has also
interests in Non-Equilibrium Thermodynamics of Quantum Systems and the Physics
of Solar Cells. |
posted 28 Jul 2015, 05:09 by info admin
Joachim D. Thomsen, Carsten Gade, Peter Bøggild, Tim J. Booth
Department of Micro and Nanotechnology, Technical University of Denmark
Transmission
electron microscopy is a characterization tool able to obtain atomic scale
resolution, and can also be used to nanopattern graphene. We have designed a
micro-fabricated platform with on-chip heating and electrical contacts for
in-situ environmental TEM characterization and modification of graphene and
other 2D materials. We will present our initial results on graphene
constrictions and interflake conductance of twisted bilayers.
Joachim
Dahl Thomsen is a PhD student in the Nanocarbon Group at the Department of
Micro and Nanotechnology, Technical University of Denmark (DTU), under
supervision of Associate Professor Tim J. Booth and Professor Peter Bøggild. He
works with in-situ transmission electron microscopy experiments (TEM) involving
patterning and electrical characterization of graphene and other 2D materials,
as well as optimization and micro-fabrication of platforms compatible with TEM
holders for such experiments. Joachim received his M.Sc. degree in Physics and
Nanotechnology from DTU in 2014 where he worked with cleanroom
micro-fabrication of flexible arrays of photodetectors in his final project. |
posted 28 Jul 2015, 05:06 by info admin
Ling Zhang, Jens Ulstrup, Jingdong Zhang*
Department of Chemistry, NanoChemistry group, Technical University of Denmark (DTU), Denmark,
Noble
metal nanoparticles (NPs), such as platinum (Pt) and palladium (Pd) NPs are
promising catalysts for dioxygen reduction and oxidation of molecules such as
formic acid and ethanol in fuel cells. Carbon nanomaterials are ideal
supporting materials for electrochemical catalysts due to their good
conductivity, chemical inertness and low cost [1]. Improvement of catalytic
efficiency and stability of the NPs is, however, essential for their wider
applications in electrochemical energy conversion/storage. The activities of
noble metal catalysts depend not only on their size, composition, and shapes
[2] but also on their interfacial interaction with the supporting electrodes.
In this work we aim at chemical production of size and shape controlled,
specifically 22 nm cubic Pd NPs, and further understanding of the Pd NPs as
electrocatalysts at the nanometer scale using both scanning tunneling
microscopy (STM) and atomic force microscopy (AFM) which have proved to be
highly efficient techniques to map the in
situ structures of self-assembled molecular monolayers at molecular or
sub-molecular resolution [3]. Electrocatalysis of the Pd NPs immobilized on
atomically flat, highly oriented pyrolytic graphite (HOPG) will be investigated
by electrochemical SPM. This study offers promise for development of new
high-efficiency catalyst types with low-cost for fuel cell technology.
- Y. S. Jeong, J.-B. Park, H.-G. Jung, J. Kim, X.
Luo, J. Lu, L. Curtiss, K. Amine, Y.-K. Sun, B. Scrosati and Y. J. Lee, Nano Lett., 2015, 15, 4261-4268.
- L. Zhang, W. Niu and G. Xu, Nano Today, 2012, 7, 586-605.
- J. Zhang, A. C.
Welinder, Q. Chi and J. Ulstrup, Phys.
Chem. Chem. Phys., 2011, 13,
5526-5545.
Ling
Zhang is a postdoc in the NanoChemistry group, Department of Chemistry,
Technical University of Denmark (DTU). The current project is supported by The
H.C. Ørsted COFUND Program. Her research interests focus on shape controlled
synthesis of colloidal noble metal nanocrystals and their electrochemical
catalytic properties, electron transfer of molecules and biomolecules, and
electrochemical catalysis of 2D materials. She has a strong expertise in
scanning probe microscopy, electrochemical catalysis, synthesis of shape
controlled colloidal noble metal nanocrystals, and structural analysis of
nanoparticles. She obtained her Ph. D. degree at Changchun Institute of Applied
Chemistry, Chinese Academy of Sciences (CAS) in 2014 and a bachelor degree at
Department of Chemistry of Jilin University in 2008. She worked at Department
of Physics, Hong Kong Polytechnic University as a Research Associate in the
electrocatalysis of 2D materials in 2014. She won the scholarship of the joint
CAS-CNRS doctoral promotion program and worked on enzyme projects at Université
Paris Diderot in 2012. She has published
more than 20 papers, including papers in ACS
Nano, Nano Today, and Analytical Chemistry, and has attended
five international conferences in nanomaterials and electrochemistry. |
posted 28 Jul 2015, 05:02 by info admin
Sharali Malik, Colin Liebscher, George Kostakis, Di Wang, Stefanie Portratz, Silviu Balaban, Carmen Balaban
Institute of Nanotechnology (INT), Karlsruhe Institute of Technology (KIT), D-76131 Karlsruhe, Germany. Aix-Marseille Université, Institut des Sciences Moléculaires de Marseille, 13397 Marseille cedex 20, France.
Few-layer graphene (less than 10 stacked layers)
possess outstanding electronic and mechanical properties. However, graphene has
a gapless band-structure and is not solution processable. Chemical
functionalization has been used to address these problems by covalent
modification of graphene’s π-electron system in association with wet chemical
exfoliation. Here we show new synthetic methods which also achieves this goal.
Starting with pristine graphite we have obtained few-layer functionalized
graphene. These materials were characterized by Raman spectroscopy, x-ray
diffraction and TEM. In this poster, we show that, we can apply analagous
methods to those we reported to functionalize carbon nanotubes for the
preparation of large quantities of graphene sheets. The research picture shows
a detail HRTEM view of a graphene and FLG flake.
Sharali Malik is a Chartered Chemist
with many years practical experience as a scientist in academia as well as in
industry. This includes three years’ experience of battery R&D with Varta
Ltd, three years’ experience of computer
modeling of long-range transmission of air pollutants in Europe (EMEP/MSC-W),
three years’ experience of advising on, implementing and enforcing Health and
Safety at Work as a UK Government
Inspector, and fourteen years’ experience of Physical Chemistry research in his
current position at Karlsruhe Institute of Technology (KIT) in the Institute of
Nanotechnology (INT) working on the Synthesis and Characterization of
Nano-Carbon Materials. |
posted 28 Jul 2015, 04:58 by info admin
F. Anselm Rasmussen, K. Sommer ThygesenCenter for Nanostructured Graphene, Dept. of Physics, Technical University of Denmark
 We present a comprehensive first-principles study of the electronic structure of 51 semiconducting monolayer transition metal dichalcogenides and -oxides in the 2H and 1T hexagonal phases. The quasiparticle (QP) band structures with spin-orbit coupling are calculated in the G0W0 approximation and comparison is made with different density functional theory (DFT) descriptions. Pitfalls related to the convergence of GW calculations for 2D materials are discussed together with possible solutions. The monolayer band edge positions relative to vacuum are used to estimate the band alignment at various heterostructure interfaces. The sensitivity of the band structures to the inplane lattice constant is analysed and rationalized in terms of the electronic structure. Finally, the q-dependent dielectric functions and effective electron/hole masses are obtained from the QP band structure and used as input to a 2D hydrogenic model to estimate exciton binding energies.
 Filip Anselm Rasmussen is working as a PhD student at the Center for Nanostructured Graphene (CNG) and Center for Atomic Scale Materials Design (CAMd) at the Department of Physics at the Technical University of Denmark under the supervision of Professor Kristian Thygesen. His work aims at calculating the electronic excitations of novel 2D materials using computational first principles methods. |
posted 28 Jul 2015, 04:01 by info admin
Arnab
Halder and Qijin Chi*
NanoChemistry
Group, Department of Chemistry, Technical University of Denmark, Kongens Lyngby
2800, Denmark. *E-mail: cq@kemi.dtu.dk
Graphene has emerged as a wonder material in
many fields ranging from physics and chemistry to biology in the past decade. [1]
Wet-chemical synthesis methods offer low-cost production and facile
functionalization of single-layered and solution suspended biocompatible
graphene. [2] We here used a biologically active molecule “Dopamine” (DA) for
the biofunctionalization. The unique properties of dopamine (DA) allow to be
used simultaneously as a reducing agent for GO reduction and as a capping
ligand to stabilize and decorate the resulting reduced GO (RGO) surface for
further functionalization. Moreover, as the dopamine moiety contains a redox
couple group, the hybrid material can be highly applicable to electrochemical
sensing. The catechol group of dopamine was selectively protected to prevent
from self-polymerization and undesirable side chain reactions. [3] After the
coupling reaction with graphene oxide, deprotection reaction was carried out to
recover free catechol groups in the RGO-DA nanocomposite. The HQ/Q- redox
couple in DA moiety can be highly applicable to electrochemical sensing. Here
we used this functionalized material for the electrochemical sensing of
melamine with ultra-high sensitivity.
- D. R. Dreyer, S. Park, C. W. Bielawski and R. S.
Ruoff, Chemical Society Reviews 2010, 39, 228-240.
- N. Zhu, S. Han, S. Gan,
J. Ulstrup and Q. Chi, Advanced
Functional Materials 2013, 23, 5297-5306.
- A. Halder, M. Zhang, G. Olsen and Q. Chi, Manuscript
under preparation, 2015
Arnab
Halder is currently a PhD student of Nanochemistry group at the Department of
Chemistry, Technical University of Denmark. His research focuses on the biocompatible
engineering functionalization of Graphene nanomaterials and their application
in chemosensors and biosensors. |
posted 28 Jul 2015, 03:53 by info admin
Jonas D. Buron1, Filippo Pizzocchero1, Peter U. Jepsen2, Dirch H. Petersen1, José M. Caridad1, Bjarke S. Jessen1, Timothy J. Booth1,3, and Peter Bøggild1,3
1DTU Nanotech - Department of Micro- and Nanotechnology, Technical University of Denmark, Building 345 Ørsteds Plads, 2800 Kgs. Lyngby, Denmark
2DTU Fotonik - Department of Photonics Engineering, Technical University of Denmark, Building 343 Ørsteds Plads, 2800 Kgs. Lyngby, Denmark
3DTU Center for Nanostructured Graphene (CNG), DTU Nanotech - Department of Micro- and Nanotechnology, Technical University of Denmark, Building 345 Ørsteds Plads, 2800 Kgs. Lyngby, Denmark
 Carrier
mobility and chemical doping level are essential figures of merit for graphene,
and large-scale characterization of these properties and their uniformity is a
prerequisite for commercialization of graphene for electronics and electrodes.
However, existing mapping techniques cannot directly assess these vital
parameters in a non-destructive way. By deconvoluting carrier mobility and
density from non-contact terahertz spectroscopic measurements of conductance in
graphene samples with terahertz-transparent backgates, we are able to present
maps of the spatial variation of both quantities over large areas. The
demonstrated non-contact approach provides a drastically more efficient
alternative to measurements in contacted devices, with potential for aggressive
scaling towards wafers/minute. The observed linear relation between conductance
and carrier density in chemical vapour deposition graphene indicates dominance
by charged scatterers. Unexpectedly, significant variations in mobility rather
than doping are the cause of large conductance inhomogeneities, highlighting
the importance of statistical approaches when assessing large-area graphene
transport properties. 1. J. D. Buron et al., Nano Lett., 2012, 12, pp. 5074-5081
Jonas Buron is currently a Post Doctoral fellow
at the Technical University of Denmark.
He is primarily interested in the ultrafast electronic and optical properties
of atomically thin materials such as graphene. He received his M.Sc. degree in
Physics from the Technical University of Denmark (2010) and a Ph.D. in Physics
(2013) from the Technical University of Denmark where he studied the terahertz
transport dynamics of graphene charge carriers. During his Ph.D, he spent 4
months in the Teraherz Optical Science laboratory at the iCeMS
(Institute for Integrated Cell-Material Sciences) studying the
terahertz nearfirled response of graphene flakes. |
posted 28 Jul 2015, 03:47 by info admin
Susanne Helene Jensen, Gunnar Olsen and Qijin Chi*
The
NanoChemistry Group, Department of Chemistry, Technical University of Denmark,
Kongens Lyngby 2800, Denmark. *E-mail: cq@kemi.dtu.dk
As
a wonder material, graphene has offered a new platform for various applications
in materials science and engineering. Chemical modification of graphene is a
key step to introduce new and desirable functionality which combines with the
intrinsic merits of graphene in optical and electronic properties. While
pristine graphene is largely chemically inert, chemically exfoliated graphene
oxide (GO), as a building-up starting material, possess the advantages
including low-cost production and facile post-functionalization with
wet-chemical methods. Both covalent and non-covalent methods are applicable to
modifications of GO nanosheets [1]. To date, many studies have shown that GO
and its reduced form, reduced graphene oxide (rGO), can be chemically modified
through different types of chemical bonding but less to none using phosphorous
bonding that could offer unique advantages such as tunable mechanical property [2].
In this work, we have systematically performed the studies on the synthesis and
structural charaterization of phosphate attached GO (P-GO) or/and rGO
nanosheets (P-rGO) [3], with the aim to generate mechanically strong as well as
super-hydrophilic nanocomposites. Some key results will form a poster presented
in this conference.
- J. B. Goods, S. A. Sydlik, J. J. Walish and T. M.
Swager, Adv. Mater. 2014, 26, 718-723.
- V.
Georgakilas et al., Chem. Rev. 2012, 112,
6156−6214.
- S. H. Jensen, Master Thesis, Technical University of
Denmark, 2015
Susanne
H. Jensen is currently a master student under supervision of associate
professor Qijin Chi, affiliated with the Nanochemistry group at the Department
of Chemistry, Technical University of Denmark, and will fulfill her master
degree in August 2015. She has studied applied chemistry and chemical
engineering through the past 6 years. Susanne is interested in the research that
can produce new materials for potential applications in chemical and mechanical
engineering, with particularly keen to polymer-graphene nanocomposites. The
poster presented in Carbonhagen 6 is the key part of the results obtained in her
master thesis project. |
posted 28 Jul 2015, 03:42 by info admin
L. Kyhla, T.
Angotb, L. Hornekaera,c, R. Bissonb
a) Interdisciplinary
Nanoscience Center, Aarhus University
b) PIIM/CNRS
Aix-Marseille Université, France
c) Institute
of Physics and Astronomy, Aarhus University, Denmark
The electronic and structural properties of
hydrogenated graphene on Ir(111) have previously been studied using scanning
tunneling microscopy (STM) and angle resolved photoemission spectroscopy
(ARPES) [1]. These techniques show nanostructured hydrogenation, templated by
the moiré structure and opening of a gap around the Fermi level of at least 450
meV [1]. Two different hydrogen adsorption configurations on graphene on Ir(111)
are still under debate [2, 3]: i) Hydrogen adsorbs on the top (vacuum) side of
the graphene sheet, stabilized by the formation of carbon-iridium bonds on the
bottom (iridium) side of the graphene; a graphane-like conformation. ii)
Chemisorption of hydrogen is stabilized by the hydrogen atom adsorption on both
sides of the graphene sheet; real graphane.
In
this work hydrogen atom adsorption on high-quality graphene on Ir(111) was
investigated using high-resolution electron energy loss spectroscopy (HREELS).
No evidence was found for hydrogen bound on both sides of a high quality
graphene sheet and phonon features strongly suggest increased interactions
between carbon and iridium atoms upon hydrogen atom exposure. The
presented results lead to the conclusion that hydrogen atoms bind only on the
top side of high-quality graphene on Ir(111).
- R. Balog, B. Jorgensen, L. Nilsson, M. Andersen, E.
Rienks, M. Bianchi, M. Fanetti, E. Laegsgaard, A. Baraldi, S. Lizzit, Z.
Sljivancanin, F. Besenbacher, B. Hammer, T. G. Pedersen, P. Hofmann and L.
Hornekaer, Nature Materials,
2010, 9, 315-319
- R. Balog, M. Andersen, B. Jorgensen, Z. Sljivancanin, B.
Hammer, A. Baraldi, R. Larciprete, P. Hofmann, L. Hornekaer and S. Lizzit,
Acs Nano, 2013, 7, 3823-3832
- K. Hyunil, T.
Balgar and E. Hasselbrink, Chemical
Physics Letters, 2012, 546,
12-17
Line Kyhl
is currently a PhD student in Nanoscience at iNANO, Aarhus University. She primarily studies functionalization of
graphene on metal surfaces using scanning tunneling microscopy (STM), Raman
spectroscopy and x-ray photoemission spectroscopy (XPS). Additionally, she is
highly involved in the National Initiative for Advanced Graphene Coatings and
Composites (NIAGRA) project developing graphene-based anti-corrosion coatings
for metals. Line has an ongoing collaboration at Aix-Marseille university
studying the vibrational properties of graphene samples using high-resolution
electron energy loss spectroscopy (HREELS). Additionally she has initiated a
collaboration at Lawrence Berkeley National Laboratory, California, studying
graphene coatings using near-ambient pressure XPS (NAPXPS). She will obtain her
PhD degree in July 2017. |
posted 27 Jul 2015, 05:08 by info admin
David M. A. Mackenzie*, Jonas D. Buron, Patrick
R Whelan, Bjarke S. Jessen, Adnan Silajdzic, Amaia Pesquera, Alba Centeno,
Amaia Zurutuza, Peter Bøggild, Dirch H. PetersenDepartment of Micro & Nanotechnology,
Technical University of Denmark,
Building 345E, 2800 Kgs. Lyngby, Denmark
As graphene is up-scaled to
wafer-sized production, it is important to have a robust, fast and accurate
method for routine characterization of the electrical properties on large
scale. Here we consider a fabrication procedure involving wafer-scale laser fabrication
of graphene devices to serve this purpose. The inherent advantages of this
method include the high speed of device fabrication and the prevention of
degradation of the electrical properties associated with traditional
lithographic methods: i.e. avoiding
contact to polymers/liquids, known to adversely affect the electrical
properties [1].
Commercially purchased CVD
graphene (covering a 4-inch Si wafer on SiO2) has metal electrodes
(Ti/Au) deposited using electron-beam evaporation through a stencil shadow
mask. The graphene is then patterned via ablation (see Figure 1) with a pulsed
laser to define large devices (Hall bars or van der Pauw geometries), enabling
the large-scale electrical properties to be tested.
Optical microscopy and Raman Spectroscopy were
used to assess ablation of the graphene, as well as stylus profilometery
indicating no damage of the SiO2 substrate. CVD graphene devices
were electrically characterized and showed comparable field-effect mobility,
doping level, on-off ratio, and conductance minimum before and after laser
ablation fabrication.
[1] A. M. Goossens, V. E. Calado, A. Barreiro, K.
Watanabe, T. Taniguchi, L. M. K. Vandersypen, Appl. Phys. Lett. 100, 073110
(2012)
David Mackenzie is a postdoctoral researcher in the Nanocarbon group
based at the Department
of Micro & Nanotechnology, Technical University of Denmark. Research
interests include fabricating graphene devices, electrical and gas sensing
measurements.
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