Laser Engineering of Graphene and Related Materials


Contact Person(s):
Dr. Emmanuel Stratakis


 Ultrafast laser processing and functionalization schemes are pursued towards the generation of graphene-based derivatives and other 2D layered nanomaterials.

 

 

Research Topics
Ultrafast Laser Micro- and Nano- processing

Abstract

Utrafast laser processing is a promissing tool for the fabrication of graphene and other two-dimensional nanomaterials for optoelectronic applications. In particular, we report on the first reduction technique, compatible with flexible, temperature sensitive substrates, for the production of transparent conductive flexible graphene electrodes. It is based on the use of femtosecond laser irradiation for the in-situ, non-thermal, reduction of spin coated grpahene oxide (GO) films on flexible substrates over a large area. Furthermore, we present a simple photochemical method for the simultaneous reduction and doping of GO sheets through pulsed UV laser irradiation of GO in liquid or gas media. Using this technique Cl and N doping was rapidly carried out at room temperature in only few minutes. Current research is focused on the application of ultrafast processing schemes for the controlled synthesis of other 2D nanomaterials including WS2 and MoS2. Potential applications of ultrafast laser synthesized and modified materials in organic electronics, particular to organic photovoltaics, field effect transistors and electron emission cathodes are investigated. The research activity is implemented with a joint effort between the Ultrafast Laser Micro- and Nano- Processing (ULMNP) group of the Institute of Electronic Structure and Laser (IESL) of the foundation for Research and Technology Hellas (FORTH) and the Nanomaterials and Organic Electronics group of the Center of Materials Technology & Photonics (CEMATEP) of the Technical Educational Institute (T.E.I) of Crete, headed by Prof. Emmanuel Kymakis. Our mission is to provide research facilities for state of the art research in the multidisciplinary field of nanotechnology and advanced electronics.Further information: http://nano.teicrete.gr/

Figure: Thermal modelling results on laser processing of a 20.1 nm graphene oxide (GO) thin film spin-coated on Poly-ethylene terephelate (PET): (Top) Cross-sectional contour plot showing the temperature distribution within a 320µm by 9µm area of the GO/PET system; (Bottom) Temperature gradient along z axis (the surface of GO film corresponds to z=0). The dashed line indicates the melting temperature of PET.



Collaborators

Prof. Emmanuel Kymakis, Dept. of Electrical Engineering, Technical Educational Institute (T.E.I) of Crete

Prof. Thomas D. Anthopoulos Department of Physics & Centre for Plastic Electronics, Imperial College London, Blackett Laboratory

Dr. G. Eda, Department of Physics, National University of Singapore


Publications

  • Flexible Organic Photovoltaic Cells with In-situ Non-thermal Photoreduction of Spin Coated Graphene Oxide
    Kymakis E., Savva K., Stylianakis M. M., Fotakis C., Stratakis E., Advanced Functional Materials, 10.1002/adfm.201202713, 2013

  • Plasmonic organic photovoltaic devices with graphene based buffer layers for stability and efficiency enhancement
    Stratakis E., Stylianakis M., Koudoumas E., Kymakis E., Nanoscale, DOI: 10.1039/C3NR00656ES, 2013

  • Free-standing graphene on microstructured silicon vertices for enhanced field emission properties
    Stratakis E., Eda G., Yamaguchi,H. Kymakis E., Fotakis C., Chhowalla M., , Nanoscale, 4,3069-3074, 2012

  • Solution-processable graphene linked to 3,5-dinitrobenzoyl as an electron acceptor in organic bulk heterojunction photovoltaic devices
    Stylianakis M.M., Spyropoulos G.D , Stratakis, E., Kymakis, E, Carbon, 50, 15, 5554–5561, 2012

  • Organic bulk heterojunction photovoltaic devices based on polythiophene - graphene composites
    Stylianakis M.M., Stratakis, E., Koudoumas E.,Kymakis E, Anastasiadis S.H., ACS Applied Materials and Interfaces, 4, 4864–4870, 2012

  • Spin coated graphene films as the transparent electrode in organic photovoltaic devices
    Kymakis, E., Stylianakis, M.M., Statakis E. Koudoumas, E., Fotakis, C, Thin Solid Films, 520 1238, 2011

Project Members
Prof. Costas Fotakis
Mr. Emmanouil Amargianitakis
Mr. George Kakavelakis
Ms. Maria Sygletoy
Ms. Kyriaki Savva
Mr. Ioannis Paradisanos
Dr. Emmanuel Stratakis



Last Updated:  15/5/2013
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