INVESTIGADORES
SANCHEZ Veronica Muriel
artículos
Título:
Adsorption of R−OH Molecules on TiO2 Surfaces at the Solid−Liquid Interface
Autor/es:
V. M. SÁNCHEZ; E. DE LA LLAVE; D. A. SCHERLIS PEREL
Revista:
LANGMUIR
Editorial:
AMER CHEMICAL SOC
Referencias:
Lugar: Washington; Año: 2011 vol. 27 p. 2411 - 2419
ISSN:
0743-7463
Resumen:
The exploration of TiO2 surface reactivity from
first-principles calculations has been almost always limited to the gas
phase, even though most of the chemically relevant applications of this
interface involve the solid−liquid boundary. The reason for this
limitation is the complexity of the solid−liquid interface, which poses a
serious challenge to standard ab initio methodologies as density
functional theory (DFT). In this work we study the interaction of H2O, CH3OH, H2O2, and HCO2H
with anatase (101) and rutile (110) surfaces in aqueous solution,
employing a continuum solvation model in a DFT framework in periodic
boundary conditions [ J. Chem. Phys. 2009, 131,
174108]. Different adsorption configurations were analyzed, examining
the effect of the first water monolayer explicitly included in the
simulation. For water and methanol, molecular adsorption was found to be
the most stable in the presence of the solvent, while for hydrogen
peroxide the preferred configuration depended on the surface. The
explicit inclusion of the first water monolayer turns out to be
important since it may play a role in the stabilization of the
adsorbates at the interface. In general, the slightly positive
adsorption energy values obtained (with respect to water) suggest that
CH3OH and H2O2 will poorly adsorb from
an aqueous solution at the titania surface. Among the three species
investigated other than water, the formic acid was the only one to
exhibit a higher affinity for the surface than H2O.