Catalyst becomes more selective after oxygen atoms' departures
Thursday, February 14, 2013 - 09:00
in Physics & Chemistry
Using chemical imaging techniques, scientists at Pacific Northwest National Laboratory proved for the first time that titanium dioxide's surface defects shelter chemicals from decays caused by ultra-violet light. The defects are tiny gaps created when oxygen atoms are missing from the surface of this popular catalyst. Conventional wisdom says the vacancies are more active than the surface. The team showed the opposite is true for photooxidation. The carbon-based carboxylic group, trimethyl acetate (TMA), remains intact if bound in the vacancies while it readily decomposes at regular, or non-vacancy, sites on the surface.