title: Photo-reduction of CO2 Using a Rhenium Complex Covalently Supported on a Graphene/TiO2 Composite.
abstract: One of the promising solutions for decreasing atmospheric CO2 is artificial photosynthesis, in which CO2 can be photoconverted into solar fuels. In this study, a rhenium complex Re(PyBn)(CO)3 Cl (PyBn=1-(2-picolyl)-4-phenyl-1H-1,2,3-triazole) was covalently grafted onto the surface of reduced graphene oxide (rGO). This was further combined with TiO2 to fabricate a novel catalyst composite TiO2 -rGO-Re(PyBn)(CO)3 Cl for CO2 photo-reduction. This hybrid composite demonstrated high selectivity conversion of CO2 into CO under xenon-lamp irradiation. Compared with the unsupported homogeneous catalyst Re(PyBn)(CO)3 Cl, the covalent immobilized catalyst composite TiO2 -rGO-Re(PyBn)(CO)3 Cl enhanced the turnover number six times and significantly improved catalyst stability. During the process of CO2 photo-reduction, intermediate species with lifetimes longer than hundreds of microseconds were observed and the formation of CO products was revealed using timeresolved infrared spectroscopy. A plausible mechanism for CO2 photo-reduction by the TiO2 -rGO-Re(PyBn)(CO)3 Cl catalyst composite has been suggested. The obtained results have implications for the future design of efficient catalyst composites for CO2 photo-conversion.
authors.affiliation: Department of Chemistry, East China University of Science and Technology, Shanghai, 200237, P. R. China.
authors.forename: Shi-Cong
authors.initials: SC
authors.lastname: Cui
authors.affiliation: School of Chemistry, University of Nottingham, University Park, Nottingham, NG7 2RD, U.K.
authors.forename: Xue-Zhong
authors.initials: XZ
authors.lastname: Sun
authors.affiliation: Department of Chemistry, East China University of Science and Technology, Shanghai, 200237, P. R. China. liujingang@ecust.edu.cn.
authors.forename: Jin-Gang
authors.initials: JG
authors.lastname: Liu
mesh_terms: D002245:Carbon Dioxide / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry*; D007700:Kinetics; D008958:Models, Molecular; D008968:Molecular Conformation; D009942:Organometallic Compounds / Q000737:chemistry*; D010084:Oxidation-Reduction; D055668:Photochemical Processes; D012211:Rhenium / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*
chemical_list: D009942:Organometallic Compounds; D002245:Carbon Dioxide; C009495:titanium dioxide; D012211:Rhenium; D006108:Graphite; D014025:Titanium
keywords: CO2 photoreduction; graphene oxide; photocatalyst; rhenium; titanium dioxide