Alexandre RICO PhD defense

Design of Soft Salt based Complexes as Potential Smart Anti-Counterfeiting Material with Tunable Luminescence Properties
Design of Soft Salt based Complexes as Potential Smart Anti-Counterfeiting Material with Tunable Luminescence Properties

Organometallics: Materials & Catalysis (OMC) team

Abstract
Luminescent materials whose optical properties can be reversibly modified under the effect of external stimuli are attracting increasing interest due to their numerous applications. Among these materials, cyclometalated platinum(II) complexes stand out for their high photoluminescence quantum yield and strong sensitivity to their environment. In this context, ionic pairs particularly double salts composed of oppositely charged ionic platinum(II) complexes emerge as especially promising candidates for the design of stimulus-responsive luminescent materials. They are characterized by Pt(II)···Pt(II) and π-π interactions between the anionic and cationic entities, offering the possibility of finely tuning their photophysical properties in response to external stimuli. This thesis focuses on the synthesis and photophysical study of several series of ionic pairs, including bimetallic Pt(II), trimetallic Pt(II), and heterobimetallic Ir(III)/Pt(II) systems, designed from cationic and anionic complexes bearing functionalized C^N or C^C ligands.
Particular attention was given to the investigation of structure-property relationships, in order to better understand the influence of structural variations on photoluminescent characteristics (absorption, emission, photoluminescence quantum yield), aggregation effects, and other optical behaviors. Finally, the chromic properties of these materials were studied to highlight their potential for security applications, particularly in the fight against counterfeiting.

Jury
Véronique Michelet, Full Professor, Univ Nice-Côte d'Azur
Julien Massue, CNRS researcher, Université Strasbourg
Olivier Siri, CNRS research Director, Université Aix-Marseille
Pascal le Poul, Associate professor, Université Rennes, ISCR
Sébastien Gauthier, Associate Professor, Université Rennes, ISCR
Sylvain Achelle, Full Professor, Université Rennes, ISCR

Contacts
Sébastien Gauthier, sebastien.gauthier@univ-rennes.fr
Sylvain Achelle, sylvain.achelle@univ-rennes.fr