DFT study of ethanol adsorption on β-Mo2C(001),

MARÍA NILDA CHASVIN ORRADRE; JUAN, ALFREDO; PISTONESI, CAROLINA

Montevideo

Workshop; V Workshop on novel methods for electronic structure calculations; 2013

We have studied the adsorption of ethanol on a β-Mo2C(001) surface model using density functional theory calculations. We employed the generalized gradient approximation (GGA) with Perdew-Burke-Ernzerhof functional (PBE) and the empirical correction proposed by S. Grimme for the Van der Waals correction. We modeled the bulk and the Mo-terminated carbide surface using a five layer slab. According to our calculations the most favorable sites for ethanol adsorption are the top sites with the OH group pointing towards the surface. Adsorption heat and vibrational frequencies are in agreement with previous experimental data [1]. Bader charge analysis revealed that the molecule withdraws charge from the surface. Also the dissociation to an ethoxy specie is energetically favorable. We compare these results with previous calculations with methanol.