Differentiated interactions in phosphate solutions: Comparing Ag(111) and Ag(100) surfaces
| Autor: | M.I. Rojas, Claudia Beatriz Salim Rosales, Lucia Bernardita Avalle |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2017 |
| Předmět: |
General Chemical Engineering
Otras Ciencias Químicas Inorganic chemistry Ciencias Químicas AG(100) AG(111) 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology Phosphate 01 natural sciences DFT 0104 chemical sciences Analytical Chemistry chemistry.chemical_compound chemistry Electrochemistry CYCLIC VOLTAMMETRY PHOSPHATES 0210 nano-technology CIENCIAS NATURALES Y EXACTAS Nuclear chemistry |
| Popis: | The electrochemical behavior of phosphate species on Ag(111) and Ag(100) single crystal surfaces was studied by experimental techniques and theoretical calculations. Characteristic cathodic/anodic potential peaks (Vp) appear in the current density-potential curves (j–V) for H2PO4−, H3PO4, and in the case of PO43− for concentrations lower than 0.1 M, where the interaction is stronger for the Ag(100) electrode. This demonstrate that the adsorption is sensitive to the surface structure. The adsorption energy (Eads) of the different species on both surfaces was studied by means of DFT-vdW calculations. All phosphate species have tri-dentate binding. The |Eads| increased for the H3PO4; H2PO4−; HPO42− and PO43− sequence, and the tetrahedral structures are compressed. Although the same trend was observed on both crystalline surfaces, the films have the symmetry of the substrate, C3v and C4v. The influence of hydroxide co-adsorption was studied for different [HPO42−]/[PO43−] ratios in solution. The strength of adsorption obtained from experimental and theoretical calculations show an excellent qualitative correlation. Fil: Salim Rosales, Claudia Beatríz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentina Fil: Rojas, Mariana Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina Fil: Avalle, Lucia Bernardita. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Catamarca. Facultad de Ciencias Exactas y Naturales; Argentina |
| Databáze: | OpenAIRE |
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