title: Designing NHC-Copper(I) Dipyridylamine Complexes for Blue Light-Emitting Electrochemical Cells.
abstract: This study presents the influence of various substituents on the photophysical features of heteroleptic copper(I) complexes bearing both N-heterocyclic carbene (NHC) and dipyridylamine (dpa = dipyridylamine skeleton corresponding to ligand L1) ligands. The luminescent properties have been compared to our recently reported archetypal blue emitting [Cu(IPr)(dpa)][PF6] complex. The choice of the substituents on both ligands has been guided to explore the effect of the electron donor/acceptor and "push-pull" on the emission wavelengths and photoluminescence quantum yields. A selection of the best candidates in terms of their photophysical features were applied for developing the first blue light-emitting electrochemical cells (LECs) based on copper(I) complexes. The device analysis suggests that the main concern is the moderate redox stability of the complexes under high applied driving currents, leading to devices with moderate stabilities pointing to a proof-of-concept for further development. Nevertheless, under low applied driving currents the blue emission is stable, showing performance levels competitive to those reported for blue LECs based on iridium(III) complexes. Overall, this work provides valuable guidelines to tackle the design of enhanced NHC copper complexes for lighting applications in the near future.
authors.affiliation: Normandie Université , LCMT, ENSICAEN, UNICAEN, CNRS, 14000-Normandie, France.
authors.forename: Margaux
authors.initials: M
authors.lastname: Elie
authors.affiliation: CEA, LIST , Laboratoire Capteurs et Architectures Électroniques, F-91191 Gif-sur-Yvette Cedex, France.
authors.forename: Fabien
authors.initials: F
authors.lastname: Sguerra
authors.affiliation: Division of Theoretical Chemistry, Department of Physics, Chemistry and Biology, Linköping University , SE-581 83 Linköping, Sweden.
authors.forename: Florent
authors.initials: F
authors.lastname: Di Meo
authors.affiliation: Department of Chemistry and Pharmacy, University of Erlangen-Nuremberg , Egerlandstrasse 3, DE-91058 Erlangen, Germany.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Weber
authors.affiliation: Normandie Université , LCMT, ENSICAEN, UNICAEN, CNRS, 14000-Normandie, France.
authors.forename: Ronan
authors.initials: R
authors.lastname: Marion
authors.affiliation: Normandie Université , LCMT, ENSICAEN, UNICAEN, CNRS, 14000-Normandie, France.
authors.forename: Adèle
authors.initials: A
authors.lastname: Grimault
authors.affiliation: Normandie Université , LCMT, ENSICAEN, UNICAEN, CNRS, 14000-Normandie, France.
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Lohier
authors.affiliation: Normandie Université , LCMT, ENSICAEN, UNICAEN, CNRS, 14000-Normandie, France.
authors.forename: Aurélie
authors.initials: A
authors.lastname: Stallivieri
authors.affiliation: PPSM, CNRS, UMR8531 & Institut d'Alembert FR3242, ENS Cachan, Paris Saclay University , 91190 Saint-Aubin, France.
authors.forename: Arnaud
authors.initials: A
authors.lastname: Brosseau
authors.affiliation: PPSM, CNRS, UMR8531 & Institut d'Alembert FR3242, ENS Cachan, Paris Saclay University , 91190 Saint-Aubin, France.
authors.forename: Robert B
authors.initials: RB
authors.lastname: Pansu
authors.affiliation: Normandie Université , LCMT, ENSICAEN, UNICAEN, CNRS, 14000-Normandie, France.
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Renaud
authors.affiliation: Division of Theoretical Chemistry, Department of Physics, Chemistry and Biology, Linköping University , SE-581 83 Linköping, Sweden.|Swedish e-Science Research Centre (SeRC), Linköping University , SE-581 83 Linköping, Sweden.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Linares
authors.affiliation: CEA, LIST , Laboratoire Capteurs et Architectures Électroniques, F-91191 Gif-sur-Yvette Cedex, France.
authors.forename: Matthieu
authors.initials: M
authors.lastname: Hamel
authors.affiliation: Department of Chemistry and Pharmacy, University of Erlangen-Nuremberg , Egerlandstrasse 3, DE-91058 Erlangen, Germany.
authors.forename: Rubén D
authors.initials: RD
authors.lastname: Costa
authors.affiliation: Normandie Université , LCMT, ENSICAEN, UNICAEN, CNRS, 14000-Normandie, France.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Gaillard
keywords: TADF; TD-DFT; blue emitters; copper(I) complexes; electroluminescence; light-emitting electrochemical cells