Adsorption of sulfate, bisulfate and sulfuric acid on silver surfaces: a theoretical study

P. PAREDES OLIVERA; E. M. PATRITO; HARRELL SELLERS

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 1998 vol. 418 p. 376 - 376

he adsorption of sulfate, bisulfate and sulfuric acid is investigated on the 111, 110 and 100 surfaces of silver by means of ab-initio calculations performed at the Hartree Fock+second order perturbation level of theory. We consider the following aspects of the adsorption process: binding energies on different surfaces and coordination sites, charge transfer and adsorbate relaxation. Theadsorption of sulfate is studied in more detail on the three metal surfaces. Sulfate binding energies in the range 110?180 kcal/mol are calculated for the different surfaces and coordinations investigated. The highest binding energies were obtained for the more open 110 surface. On a given surface, coordination via three oxygen atoms is more stable than via only one. For bisulfate andsulfuric acid we obtained binding energies of 58 and 27 kcal/mol on the Ag(111) and Ag(100) surfaces, respectively. The charge transferred to the metal is 0.2 electrons for bisulfate and 0.4?0.6 electrons for sulfate. A li