Bidoia, Ederio Dino [UNESP]2014-05-272014-05-272005-06-07Chemical Physics Letters, v. 408, n. 1-3, p. 1-4, 2005.0009-2614http://hdl.handle.net/11449/68284Probe-beam deflection (PBD) was used to monitor concentration gradients of anions adjacent to the surface of a platinum electrode in acidic aqueous media containing H3PO4. PBD can measure the potential-dependent extent of adsorption of H2PO4- on the Pt electrode surface and permits the Langmuir isotherm to be fitted to the experimental data. The value thus obtained for the surface concentration was 1.3 × 10-11 mol mm -2, or 1.7 atoms of Pt per H2PO4-. Also, the electron transfer number obtained was 0.24, signifying an incomplete transfer of charge, and the equilibrium constant is 1.80 suggesting a reversible adsorption process. © 2005 Elsevier B.V. All rights reserved.1-4engAdsorptionCharge transferElectrodesNegative ionsPhosphatesPlatinumSolutionsSpectrometersAnion adsorptionDihydrogenElectrode surfacesProbe-beam detectionIonsArtigo10.1016/j.cplett.2005.03.138WOS:000229655200001Acesso restrito2-s2.0-1884439377192203485835600430000-0001-7040-1983