Anatase (100) thin film surface computational model for photoelectrochemical cell



Using computational approaches, one is able to better understand electron transfer and specific atomistic behaviors in semiconductor materials; it is also more cost and time effective than experimental methods. If computed semiconductor characteristics show promise, experimentalists can synthesize and further examine the structure. Specifically, doping TiO2 thin film surfaces with platinum and ruthenium have shown great promise for efficient H2 production and is beneficial in comparison to other materials such as the pure silicon used for most of today's solar cells. In computational studies, TiO2 anatase thin film (100) surfaces are doped with platinum and ruthenium. The formulas used are Pt2Ti32O72H16 or Ru2Ti32O72H16 with the (100) crystallographic surface exposed and covered with a monolayer of water. Optimization is completed by density functional theory and Perdue Burke Ernzerhof, (PBE) in Vienna Ab-initio simulation package (VASP) software. The density of states, absorption spectra, and partial charge densities are compared between slabs doped by the two elements as well as Ti32 O72H16 with no dopant as a standard for reference. The information can be used to show the mechanism of how doping the titanium dioxide nanocrystals facilitates photoinduced charge transfer at the surfaces, which is useful in understanding photoelectrochemical water splitting. © 2012 Wiley Periodicals, Inc.