The adsorption of metal-phthalocyanine (MPc) layers (M = Fe, Co, Cu) assembled on graphene/Ir(111) is studied by means of temperature-programmed X-ray photoemission spectroscopy (XPS) and near-edge X-ray absorption fine structure (NEXAFS). The balance between interaction forces among the organometallic molecules and the underlying graphene gives rise to flat-lying molecular layers, weakly interacting with the underlying graphene. Further MPc layers pile up face-on onto the first layer, up to a few nanometers thickness, as deduced by NEXAFS. The FePc, CoPc, and CuPc multilayers present comparable desorption temperatures, compatible with molecule-molecule interactions dominated by van der Waals forces between the π-conjugated macrocycles. The MPc single layers desorb from graphene/Ir at higher temperatures. The CuPc single layer desorbs at lower temperature than the FePc and CoPc single layers, suggesting a higher adsorption energy of the FePc and CoPc single layers on graphene/Ir with respect to CuPc, with increasing molecule-substrate interaction in the order ECuPc < EFePc ∼ ECoPc. © 2013 American Chemical Society.
Energetics and hierarchical interactions of metal-phthalocyanines adsorbed on graphene/Ir(111) / Scardamaglia, Mattia; Claudia, Struzzi; Silvano, Lizzit; Matteo, Dalmiglio; Paolo, Lacovig; Alessandro, Baraldi; Mariani, Carlo; Betti, Maria Grazia. - In: LANGMUIR. - ISSN 0743-7463. - 29:33(2013), pp. 10440-10447. [10.1021/la401850v]
Energetics and hierarchical interactions of metal-phthalocyanines adsorbed on graphene/Ir(111)
SCARDAMAGLIA, MATTIA;MARIANI, CARLO;BETTI, Maria Grazia
2013
Abstract
The adsorption of metal-phthalocyanine (MPc) layers (M = Fe, Co, Cu) assembled on graphene/Ir(111) is studied by means of temperature-programmed X-ray photoemission spectroscopy (XPS) and near-edge X-ray absorption fine structure (NEXAFS). The balance between interaction forces among the organometallic molecules and the underlying graphene gives rise to flat-lying molecular layers, weakly interacting with the underlying graphene. Further MPc layers pile up face-on onto the first layer, up to a few nanometers thickness, as deduced by NEXAFS. The FePc, CoPc, and CuPc multilayers present comparable desorption temperatures, compatible with molecule-molecule interactions dominated by van der Waals forces between the π-conjugated macrocycles. The MPc single layers desorb from graphene/Ir at higher temperatures. The CuPc single layer desorbs at lower temperature than the FePc and CoPc single layers, suggesting a higher adsorption energy of the FePc and CoPc single layers on graphene/Ir with respect to CuPc, with increasing molecule-substrate interaction in the order ECuPc < EFePc ∼ ECoPc. © 2013 American Chemical Society.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.