LUQUE GUILLERMINA LETICIA
Congresos y reuniones científicas
Título:
Change in the properties of graphene sheet modified with different functional groups: a DFT study
Autor/es:
G. L. LUQUE, M. I. ROJAS, E. P. M. LEIVA.
Reunión:
Congreso; International Materials Research Congress IMRC XIX; 2010
Resumen:
Graphene has attracted considerable attention from both the experimental and theoretical scientific communities since it was discovered and successfully isolated from bulk graphite just a few years ago [1]. Its unique properties such as high surface area, fast electron transfer rate, high thermal conductivity, excellent mechanical stiffness, good biocompatibility [2] and low fabrication procedure cost, makes it a perfect alternative to carbon nanotubes in the construction of electrochemical (bio)sensors.
In the present work, using Density Functional Theory (DFT) calculations, we investigate the functionalization of the graphene layer with carboxyl [3], amino, and thiol groups considering perfect and defective layers. In the last case we take into account Stone-Wales (SW) defects which are common defects on graphene.
The chemical functionalization of these surfaces with electron donor or acceptor groups modified the physical (electric properties) and chemical properties of the layer. Thus, it is of technological importance to understand where this functionalization takes place and how the properties change.
We compare the adsorption energies of the hydrogen peroxide on the different functionalized layers and also how the functionalization modified the catalytic properties of the layer.
The local minima where found through the conjugate gradient (CG) technique, employing DFT calculations with spin polarization (sp) as implemented in SIESTA [4] and the minimum energy path for the reaction and determine the energy barriers we performed state-of-the-art calculation methods using the nudged elastic band method (NEB) [5].
[1] K.S. Novoselov, A.K. Geim, S.V. Morozov, D. Jiang, Y. Zhang, S. V. Dubonos, Science 306 (2004) 666.
[2] H. Chen, M.B. Müller, K.J. Gilmore, G.G. Wallace, D. Li, Adv. Mater. 20 (2008) 3557.
[3] G.L. Luque, M.I. Rojas, G.A. Rivas, E.P.M. Leiva, submitted to Electrochimica Acta.
[4] J. M. Soler, E. Artacho, J. D. Gale, A. García, J. Junquera, P. Ordejón, D. Sánchez-Portal, J. Phys.: Condens. Matter 14 2745 (2002).
[5] G. Henkelman, B.P. Uberuaga, H. Jonsson, J. Chem. Phys. 113 (2000) 9901-04.
G. Henkelman, H. Jonsson, J. Chem. Phys. 113 (2000) 9978-85.
In the present work, using Density Functional Theory (DFT) calculations, we investigate the functionalization of the graphene layer with carboxyl [3], amino, and thiol groups considering perfect and defective layers. In the last case we take into account Stone-Wales (SW) defects which are common defects on graphene.
The chemical functionalization of these surfaces with electron donor or acceptor groups modified the physical (electric properties) and chemical properties of the layer. Thus, it is of technological importance to understand where this functionalization takes place and how the properties change.
We compare the adsorption energies of the hydrogen peroxide on the different functionalized layers and also how the functionalization modified the catalytic properties of the layer.
The local minima where found through the conjugate gradient (CG) technique, employing DFT calculations with spin polarization (sp) as implemented in SIESTA [4] and the minimum energy path for the reaction and determine the energy barriers we performed state-of-the-art calculation methods using the nudged elastic band method (NEB) [5].
[1] K.S. Novoselov, A.K. Geim, S.V. Morozov, D. Jiang, Y. Zhang, S. V. Dubonos, Science 306 (2004) 666.
[2] H. Chen, M.B. Müller, K.J. Gilmore, G.G. Wallace, D. Li, Adv. Mater. 20 (2008) 3557.
[3] G.L. Luque, M.I. Rojas, G.A. Rivas, E.P.M. Leiva, submitted to Electrochimica Acta.
[4] J. M. Soler, E. Artacho, J. D. Gale, A. García, J. Junquera, P. Ordejón, D. Sánchez-Portal, J. Phys.: Condens. Matter 14 2745 (2002).
[5] G. Henkelman, B.P. Uberuaga, H. Jonsson, J. Chem. Phys. 113 (2000) 9901-04.
G. Henkelman, H. Jonsson, J. Chem. Phys. 113 (2000) 9978-85.
