| AVS 55th International Symposium & Exhibition | |
| Surface Science | Tuesday Sessions |
| Session SS-TuP |
| Session: | Surface Science Poster Session |
| Presenter: | J. Graciani, Brookhaven National Laboratory |
| Authors: | J. Graciani, Brookhaven National Laboratory A. Nambu, Brookhaven National Laboratory J. Evans, Universidad Central de Venezuela J.A. Rodriguez, Brookhaven National Laboratory J.F. Sanz, Universidad de Sevilla, Spain |
| Correspondent: | Click to Email |
N-doping of titania makes possible photocatalytic activity for the splitting of water, and other reactions, under visible light. Here we show from both theory and experiment that Au preadsorption on TiO2 surfaces significantly increases the reachable amount of N implanted in the oxide. The stabilization of the embedded N is due to an electron transfer from the Au 6s levels toward the N 2p levels, which also increases the Au-surface adhesion energy. Theoretical calculations predict that Au also can stabilize embedded N in other metal oxides with photocatalytic activity such as SrTiO3 and ZnO, producing new states above the valence band or below the conduction band of the oxide. In experiments, the Au/TiNxO2-y system was found to be more active for the dissociation of water than pure TiO2 or TiO2-y. Furthermore, the Au/TiNxO2-y surfaces were able to catalyze the production of hydrogen through the water-gas shift reaction (WGS) at elevated temperatures (575- 625 K) displaying a catalytic activity superior to that of pure copper (the most active metal catalysts for the WGS) or Cu nanoparticles supported on ZnO.