Different reactivities of TiO2 polymorphs: comparative DFT calculations of water and formic acid adsorption at anatase and brookite TiO2 surfaces

Abstract

Density functional theory calculations have been performed to determine the relationship between structures and reactivity of anatase and brookite TiO 2 surfaces. Brookite TiO2(210) has the same structural building block of anatase TiO2(101), but interatomic distances are slightly shorter and the blocks are arranged in a different way. Our calculations show that these differences significantly change the reactivity toward adsorption of various molecules, and most importantly, generate highly active sites at the junction between different structural units on brookite TiO2(210). These results suggest that brookite TiO2(210) would exhibit distinct activity, which may be useful in catalytic and photocatalytic applications. © 2008 American Chemical Society.