Atomistic simulation on water behaviour in titania nanopores

ESTEFANA GONZALEZ SOLVEYRA; EZEQUIEL DE LA LLAVE; GALO J. A. A. SOLER-ILLIA; MOLINERO, VALERIA; DAMIAN A. SCHERLIS PEREL

Holderness, NH, EE.UU.

Conferencia; Gordon Research Conference on Water and Aqueous Solutions; 2010

Gordon Research Conference

In the present work we seek to investigate the structure and mobility of liquid water contained in titanium dioxide nanopores of different diameters, as a function of the radius and the distance to the the surface through molecular dynamics methods. To that end, we are working with different diameters (14, 26 and 80 Å) cylindric channels of rutile (110) constructed from the bulk structure, with the premise of maximum coordination for the surface Ti atoms. Water is represented by the SPC/E model and the interaction of water with the metal oxide is modeled by the ab initio forcefields derivated by Bandura et al. (JPC B, 107, 40, 2003). Ab initio studies confirmed by synchrotron X-ray structures (Zang et al., Langmuir, 20, 4954, 2004) shows that associative adsoption of water molecules on rutile (110) surfaces is more stable than dissociative, thus we are working with non-hydroxilated channel surfaces, considering only molecular adsorption for the first layer of water. In this work we explore structural parameters, such as the radial density profile, radial distribution function and number of hydrogen bonds, and mobility parameters, diffusion coefficients, as a function of water filling and surface distance, as to accomplish an atomistic understanding of water behaviour in confined geometries.