Photoreduction of CO2 on titania: Quantum chemical calculations and experimental studies

FUEL 158

Venkata Pradeep Indrakanti, vxi103@psu.edu, The Energy Institute and Department of Energy and Mineral Engineering, Pennsylvania State University, 110 Hosler Bldg, University Park, PA 16801, James D Kubicki, kubicki@geosc.psu.edu, Department of Geosciences and Earth and Environmental Systems Institute, Pennsylvania State University, 335 Deike building, University Park, PA 16802, Alexander V. Mitin, aum20@psu.edu, Earth and Environmental Systems Institute, 2217 Earth-Engineering Sciences Building, University Park, PA 16802-6813, and Harold Schobert, schobert@ems.psu.edu, The EMS Energy Institute and Department of Energy and Mineral Engineering, The Pennsylvania State University, 204 Research East Bldg, University Park, PA 16802.
One of the strategies for CO2 utilization is its activation in the presence of a photosensitizer and light. We present post-Hartree-Fock calculations of the excited states of CO2 adsorbed on titania and preliminary experimental studies of the photoactivity of lanthanide-doped titania. We performed single point Symmetry-Adapted Cluster-Configuration Interaction (SAC-CI) calculations of the excited states of carbonate-like species adsorbed on small clusters from (010) surface plane of anatase form of titania. Unrelaxed excited state Mulliken population analyses obtained from SAC-CI calculations indicate that the CO2 moiety gains electrons in the first five excited singlet states, although the carbon atom loses some electronic charge. We find evidence for charge transfer from CO2 to the cluster in the sixth excited singlet state, which is promising for the formation of surface CO species via O-O bond formation. Preliminary results of CO2 photoreduction using lanthanide-doped TiO2 will also be discussed.
 

Hybrid Nanotechnologies for an Enhanced CO2 Fixation
1:30 PM-5:50 PM, Tuesday, April 8, 2008 Morial Convention Center -- Rm. 240/241, Oral

Division of Fuel Chemistry

The 235th ACS National Meeting, New Orleans, LA, April 6-10, 2008