Autor: |
Hemmeter D; Lehrstuhl für Physikalische Chemie II, Universität Erlangen-Nürnberg, Egerlandstraße 3, Erlangen, Germany. hans-peter.steinrueck@fau.de., Merlinsky LS; Departamento de Química Inorgánica, Analítica y Química Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina. fwilliams@qi.fcen.uba.ar.; Instituto de Química Física de los Materiales, Medio Ambiente y Energía, CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina., Baraldo LM; Departamento de Química Inorgánica, Analítica y Química Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina. fwilliams@qi.fcen.uba.ar., Maier F; Lehrstuhl für Physikalische Chemie II, Universität Erlangen-Nürnberg, Egerlandstraße 3, Erlangen, Germany. hans-peter.steinrueck@fau.de., Williams FJ; Departamento de Química Inorgánica, Analítica y Química Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina. fwilliams@qi.fcen.uba.ar.; Instituto de Química Física de los Materiales, Medio Ambiente y Energía, CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina., Steinrück HP; Lehrstuhl für Physikalische Chemie II, Universität Erlangen-Nürnberg, Egerlandstraße 3, Erlangen, Germany. hans-peter.steinrueck@fau.de. |
Abstrakt: |
The interaction of metal complexes with ionic liquids, with a particular focus on the stability and surface concentration of the metal centers, is crucial in applications involving catalysts based on supported ionic liquids. In this study, we synthesized the complexes [Ru(tpy)(bpy)Cl][PF 6 ] and [Ru(tpy)(dcb)Cl][PF 6 ] (tpy = 2,2',2''-terpyridine, bpy = 2,2'-bipyridine, dcb = 4,4'-dicarboxy-2,2'-bipyridine) and we prepared solutions using the ionic liquids (ILs) 1-ethyl-3-methylimidazolium acetate [C 2 C 1 Im][OAc] and 1-butyl-3-methylimidazolium hexafluorophosphate [C 4 C 1 Im][PF 6 ]. The chemical environment of the Ru(II) metal center and the interfacial behavior of the complexes in the different IL solutions were determined using angle-resolved X-ray photoelectron spectroscopy (ARXPS). In [C 4 C 1 Im][PF 6 ], [Ru(tpy)(bpy)Cl][PF 6 ] maintains its chemical structure, while in [C 2 C 1 Im][OAc], partial changes in the chemical environment of the Ru center are indicated by XPS, likely due to ligand exchange. The presence of carboxylic acid functional groups in the bipyridyl ligand seems to inhibit this ligand exchange. The investigated complexes do not exhibit surface activity but are depleted from the IL/gas interface. These findings hold significance for the design of new supported ionic liquid phase catalysts based on Ru complexes. |