CEQUINOR   05415
CENTRO DE QUIMICA INORGANICA "DR. PEDRO J. AYMONINO"
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
DENSITY FUNCTIONAL STUDY OF LITHIUM OXIDE NANOCLUSTERS
Autor/es:
CATIVA NANCY, CARRIÓN SAMANTA MAGALÍ, LÓPEZ M. BEATRIZ
Lugar:
Buenos Aires
Reunión:
Simposio; International Symposium Challenges on lithium oxygen rechargeable batteries?; 2012
Institución organizadora:
INQUIMAE
Resumen:
Energy storage is more important today than at any time in human history. It has a key role in tackling climate change. The rechargeable lithium battery possesses the highest energy density of any electrochemicalenergy storage device. It has revolutionized consumer electronics. However, to take a leap ahead in energydensity requires radical new approaches [1, 2]. In the absence of solvent degradation the discharge of Li;O2 batteries can potentially occur via two reactions, wherein the product phase is insoluble solid peroxide (Li2O2) [3, 4] or oxide (Li2O) [5]. As these compounds constitute potential discharge products in Li-oxygen batteries, their structural and electronic properties are expected to play a key role in understanding electrochemical behavior in these systems. The aim of the present work is to study the lithium oxides Li2O and Li2O2 in nanometric range by DFT (Density Functional Theory). The calculations have been performed within DFT in the spin polarized version as implemented in the Gaussian09 package. We have used the B3PW91 functional and all clusters were optimized using the 6-311G* basis for oxygen atoms an LANL2DZ pseudopotentials for lithium atoms. Calculation of the harmonic frequencies of the stationary points was made to determine their nature and obtain zero point energies ZPE [6]. We investigated the equilibrium geometries, energetic and reactivity properties of Li2O2 and Li2O nanoclusters. Descriptors, such as ionization potential (IP), electron affinity (EA), chemical potential and chemical hardness have been used to determine the global chemical reactivity and the local reactivity was determined using Molecular Electrostatic Potential (MEP). References: 1-G. Girishkumar, B. McCloskey, A. C. Luntz, S. Swanson, and W. Wilcke. J. Phys. Chem. Lett. 1, 2193?2203, (2010). 2-Jake Christensen, Paul Albertus, Roel S. Sanchez-Carrera,Timm Lohmann,a Boris Kozinsky, Ralf Liedtke , Jasim Ahmed, and Aleksandar Kojic. Journal of the Electrochemical Society, 159 (2) R1-R30 (2012). 3-K. M. Abraham and Z. Jiang, J. Electrochem. Soc. 143, 1(1996). 4-A. Débart, A. J. Paterson, J. Bao, and P. G. Bruce, Angew. Chem., Int.Ed. 47, 4521, (2008). 5-J. Read. J.of the Electroc. Soc., 149:A1190, (2002). 6-C.Heredia, V.Ferraresi Curotto, M.B.López, Comp. Mat.Sci. 53 18? 24, (2012)
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