Characterization of charge states in conducting organic nanoparticles by X-ray photoemission spectroscopy

The metallic and semiconducting character of a large family of organic materials based on the electron donor molecule tetrathiafulvalene (TTF) is rooted in the partial oxidation (charge transfer or mixed valency) of TTF derivatives leading to partially filled molecular orbital-based electronic bands...

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Detalles Bibliográficos
Autores: Fraxedas, J., Vollmer, Antje, Koch, Norbert, Caro, Dominique de, Jacob, Kane, Faulmann, Christophe, Valade, Lydie
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2021
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/264288
Acceso en línea:http://hdl.handle.net/10261/264288
Access Level:acceso abierto
Palabra clave:Conducting nanoparticles
Tetrahiafulvalene
Bis(ethilenedithio)tetrathiafulvelene
Charge-transfer complexes
Mixed-valence materials
X-ray photoemission spectroscopy
Synchrotron radiation
Descripción
Sumario:The metallic and semiconducting character of a large family of organic materials based on the electron donor molecule tetrathiafulvalene (TTF) is rooted in the partial oxidation (charge transfer or mixed valency) of TTF derivatives leading to partially filled molecular orbital-based electronic bands. The intrinsic structure of such complexes, with segregated donor and acceptor molecular chains or planes, leads to anisotropic electronic properties (quasi one-dimensional or two-dimensional) and morphology (needle-like or platelet-like crystals). Recently, such materials have been synthesized as nanoparticles by intentionally frustrating the intrinsic anisotropic growth. X-ray photoemission spectroscopy (XPS) has emerged as a valuable technique to characterize the transfer of charge due to its ability to discriminate the different chemical environments or electronic configurations manifested by chemical shifts of core level lines in high-resolution spectra. Since the photoemission process is inherently fast (well below the femtosecond time scale), dynamic processes can be efficiently explored. We determine here the fingerprint of partial oxidation on the photoemission lines of nanoparticles of selected TTF-based conductors.