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Synthesis and optical properties of graphene quantum dots

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HAL Id: cea-02341205

https://hal-cea.archives-ouvertes.fr/cea-02341205

Submitted on 31 Oct 2019

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Synthesis and optical properties of graphene quantum

dots

Julien Lavie, Shen Zhao, Lucile Orcin Chaix, A. Narita, Jean-Sébastien

Lauret, Stéphane Campidelli

To cite this version:

Julien Lavie, Shen Zhao, Lucile Orcin Chaix, A. Narita, Jean-Sébastien Lauret, et al.. Synthesis and optical properties of graphene quantum dots. MRS Fall Meeting, Nov 2017, Boston, United States. �cea-02341205�

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corresponding author : julien.lavie@cea.fr

MRS Fall meeting 2017 - Boston, Massachusetts, November 26–December 1, 2017

SYNTHESIS AND OPTICAL PROPERTIES OF GRAPHENE QUANTUM DOTS

J. Lavie1, S. Zhao2, L. Orcin-Chaix2, A. Narita3, J-S. Lauret2 and S. Campidelli1

1 CEA, IRAMIS, NIMBE, Laboratoire d'Innovation en Chimie des Surfaces et Nanosciences, F-91191 Gif sur

Yvette, France. Email: stephane.campidelli@cea.fr

2 Laboratoire Aimé Cotton, CNRS, ENS Cachan, Université Paris-Saclay, 91405 Orsay Cedex, France 3 Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany

Abstract: The outstanding electronic, optical and mechanical properties of graphene strongly inspire the scientific community at both the fundamental and applicative levels. However, one of the main challenges of the field is the control and modification of graphene electronic properties. It is well known that when a material is reduced to nanoscale dimensions, the electronic confinement induces original size-dependent properties. For the last decade, the size reduction of graphene was mostly done through conventional top-down approaches to fabricate graphene quantum dots (GQDs)a

or graphene nanoribbons (GNRs) b

. However, top-down approaches do not allow a sufficient control of the morphology and oxidation state of the edges, which drastically impact the properties. In order to truly control, with the required level of precision, the morphology and the composition of the materials and of its edges, the bottom-up approach is the relevant way to proceedc,d

.

With the aim to study and understand the optical properties of GQD materials, we performed the bottom-up synthesise

of different families of nanoparticles exhibiting controlled shapes and edges. Because of their strong aromatic character graphene nanoparticles tend to aggregate in solution; however, for future application it is of high interest to be able to discriminate the intrinsic absorption and emission of the GQDs from those of aggregates. For example, we observed that by STM and polarized microscopy the GQDs bearing alkyl chains are forming columnar structures with liquid crystal properties in solvents. Here, we study the optical properties of graphene quantum dots as a function of their individualization. Using absorption, steady-state and time-resolved photoluminescence and photoluminescence excitation (PLE) spectroscopy, we try to establish the intrinsic optical properties of the GQDs and understand how the structure influences the properties.

Figure : Molecular Structures of GQDs and their absorption and photoluminescence spectra

a

M. Bacon, S.J. Bradley, T. Nann Part. Part. Syst. Charact. 2014, 31, 415-428.

b

M. Terrones, A.R. Botello-Méndez, J. Campos-Delgado, F. Lopez-Urias, Y.I. Vega-Cantu, F.J. Rodriguez-Marcias, A L. Elias, E. Munoz-Sandoval, A.G. Cano-Marquez, J.C. Charlier, H. Terrones, Nano Today 2010, 5, 351-372.

c

A.C. Grimsdale, K. Müllen, Angew. Chem. Int. Ed. 2005, 44, 5592 – 5629.

d A.

Narita, X.Y. Wang, X. Feng, K. Müllen Surname Chem. Soc. Rev. 2015, 44, 6616.

e

Z. Tomović, M.D. Watson, K. Müllen, Angew. Chem. Int. Ed. 2004, 17, 755 –758.

350 400 450 500 550 600 650 700 750 800 850 900 0,0 0,2 0,4 0,6 0,8 1,0 N o rma lize d i n te n si ty Wavelength (nm) PL_exc@400 nm Absorption 350 400 450 500 550 600 650 700 750 800 850 900 0,0 0,2 0,4 0,6 0,8 1,0 PL_exc@400nm Absorption N o rma lize d i n te n si ty Wavelength (nm)

Figure

Figure : Molecular Structures of GQDs and their absorption and photoluminescence spectra

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