Unexpected Mobility of Oxygen Atoms on the Surface of a Common Catalyst

Summary

While studying the behavior of oxygen atoms on the surface of titanium dioxide, a common catalyst, a team of scientists led by Igor Lyubinetsky from the William R. Wiley Environmental Molecular Sciences Laboratory (EMSL) and the Pacific Northwest National Laboratory found that when they exposed a titanium dioxide crystal that had been heated to molecular oxygen, one oxygen atom behaved as expected, but the other atom often moved one or two crystal lattice spaces away. Instead of situating itself next to its former partner, it appears that the hot oxygen atom uses the energy from the rearrangement of bonds from within the oxygen molecule and between the oxygen atom and the titanium surface to move either one or two spaces away. Because titanium dioxide is being studied for producing hydrogen from the splitting of water in solar fuel cells, this finding could be important in determining whether surface oxygen atoms interfere with the chemistry between this catalyst and other reagents. The teams work appeared on the cover of the February 21, 2008, issue of The Journal of Physical Chemistry C.