title: The quenching effect of uranyl species in the photoluminescence emission and visible-light-driven water dissociation activity of CdS and TiO2 photocatalysts.
abstract: Anchoring of uranyl species (2-4 mol%) led to the complete quenching of photoluminescence emission and the visible-light-driven water photodissociation activity of TiO2 (Degussa-P25) and a hydrothermally synthesized CdS photocatalyst. Photophysical measurements revealed a fast relaxation and the transfer of photogenerated electrons/energy from the TiO2 or CdS substrate to the acceptor uranyl moieties. Besides the position of flat band levels, significant overlap of the absorption/emission spectra of the host matrix and the surface-bound UO2(2+) species is responsible for this reverse energy transfer from a wide bandgap semiconductor to a material with a smaller band-to-band energy gap.
authors.affiliation: Catalysis Division, National Chemical Laboratory, Pune-411008, India. guptanm1611@gmail.com nm.gupta@ncl.res.in.
authors.forename: Narendra M
authors.initials: NM
authors.lastname: Gupta
authors.forename: Sarika
authors.initials: S
authors.lastname: Kelkar
authors.forename: Prakash
authors.initials: P
authors.lastname: Korake
mesh_terms: D019187:Cadmium Compounds / Q000737:chemistry*; D002384:Catalysis; D006859:Hydrogen / Q000737:chemistry; D049449:Luminescence; D008855:Microscopy, Electron, Scanning; D055668:Photochemical Processes; D012666:Semiconductors; D013057:Spectrum Analysis; D013440:Sulfides / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*; D017974:Uranium Compounds / Q000737:chemistry*; D014867:Water / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D019187:Cadmium Compounds; D013440:Sulfides; D017974:Uranium Compounds; C034939:cadmium sulfide; D014867:Water; C009495:titanium dioxide; D006859:Hydrogen; D014025:Titanium