The nature of the active sites of titanium oxide photocatalysts stabilized on an active carbon surface. A theoretical ab initio study

Ab initio quantum chemical studies at the HF/Lan12dz level of theory were performed for two different cluster models representing a graphite surface and their interactions with dihydrogen, water, and four-coordinated titanium oxide. Both associative and dissociative channels of their interaction with the specific active sites on graphite were considered. Based on the results of these calculations, it was suggested that active sites for the titanium oxides on active carbon can be represented by the OTi(OH)₃ fragment formed through the dehydroxylation of the surface OH-groups by the four-coordinated titanium oxide species. (C) 2000 Published by Elsevier Science B.V.