Not all titanium dioxide is equal when it comes to splitting water with visible light

Researchers from the Department of Energy's Pacific Northwest National Laboratory will be presenting at this year's American Chemical Society 2009 Spring Meeting in Salt Lake City, Utah. The following talk will occur on Tuesday afternoon.

Scientists are hot on the trail of materials that use light to break down contaminants for environmental cleanup or split water for hydrogen fuel production. With a splash of UV light, titanium dioxide can do just that, but researchers would like to expand its repertoire to use visible light. Doping, or adding small amounts of another element, can change a metal oxide's characteristics. PNNL's Michael Henderson and colleagues added nitrogen to different forms of titanium dioxide known as anatase and rutile, and tested how well the nitrogen-doped metal oxides performed. The team measured how a test molecule decomposed as a stand-in for half of the water-splitting reaction — the “oxidation” half of an oxidation-reduction reaction. While both metal oxides decomposed the test molecule under UV, only anatase could break it down in visible light, surprising the researchers. Henderson will talk about properties of doped anatase and rutile that might contribute to their contrasting skills.

Reference: Michael A. Henderson, T. Ohsawa. I. Lyubinetsky, Y. Du, V. Shutthanandan, S. A. Chambers, Photochemical activities of nitrogen doped rutile and anatase surfaces, Tuesday, March 24, 2 – 5:30 pm in Marriot Downtown, Salon H.

This work was supported by the Department of Energy's Chemical Sciences Division of Basic Energy Sciences, part of the Office of Science.

EMSL, the Environmental Molecular Sciences Laboratory, is a national scientific user facility sponsored by the Department of Energy's Office of Science, Biological and Environmental Research program that is located at Pacific Northwest National Laboratory. EMSL offers an open, collaborative environment for scientific discovery to researchers around the world. EMSL's technical experts and suite of custom and advanced instruments are unmatched. Its integrated computational and experimental capabilities enable researchers to realize fundamental scientific insights and create new technologies.

Pacific Northwest National Laboratory is a Department of Energy Office of Science national laboratory where interdisciplinary teams advance science and technology and deliver solutions to America's most intractable problems in energy, national security and the environment. PNNL employs 4,200 staff and has an $850 million annual budget. Ohio-based Battelle has managed PNNL since the lab's inception in 1965.