title: Visible-light-enhanced interactions of hydrogen sulfide with composites of zinc (oxy)hydroxide with graphite oxide and graphene.
abstract: Composites of zinc(oxy)hydroxide-graphite oxide and of zinc(oxy)hydroxide-graphene were used as adsorbents of hydrogen sulfide under ambient conditions. The initial and exhausted samples were characterized by XRD, FTIR, potentiometric titration, EDX, thermal analysis, and nitrogen adsorption. An increase in the amount of H(2)S adsorbed/oxidized on their surfaces in comparison with that of pure Zn(OH)(2) is linked to the structure of the composite, the relative number of terminal hydroxyls, and the kind of graphene-based phase used. Although terminal groups are activated by a photochemical process, the graphite oxide component owing to the chemical bonds with the zinc(oxy)hydroxide phase and conductive properties helps in electron transfer, leading to more efficient oxygen activation via the formation of superoxide ions. Elemental sulfur, zinc sulfide, sulfite, and sulfate are formed on the surface. The formation of sulfur compounds on the surface of zinc(oxy)hydroxide during the course of the breakthrough experiments and thus Zn(OH)(2)-ZnS heterojunctions can also contribute to the increased surface activity of our materials. The results show the superiority of graphite oxide in the formation of composites owing to its active surface chemistry and the possibility of interface bond formation, leading to an increase in the number of electron-transfer reactions.
authors.affiliation: Department of Chemistry, The City College of New York, 160 Convent Avenue, New York, New York 10031, USA.
authors.forename: Mykola
authors.initials: M
authors.lastname: Seredych
authors.forename: Oluwaniyi
authors.initials: O
authors.lastname: Mabayoje
authors.forename: Teresa J
authors.initials: TJ
authors.lastname: Bandosz
mesh_terms: D006108:Graphite / Q000737:chemistry*; D006862:Hydrogen Sulfide / Q000737:chemistry*; D006878:Hydroxides / Q000737:chemistry*; D008027:Light; D008855:Microscopy, Electron, Scanning; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction; D017967:Zinc Compounds / Q000737:chemistry*
chemical_list: D006878:Hydroxides; D017967:Zinc Compounds; D006108:Graphite; C052745:zinc hydroxide; D006862:Hydrogen Sulfide