title: Chiral Iridium(III) Complexes in Light-Emitting Electrochemical Cells: Exploring the Impact of Stereochemistry on the Photophysical Properties and Device Performances.
abstract: Despite hundreds of cationic bis-cyclometalated iridium(III) complexes having been explored as emitters for light-emitting electrochemical cells (LEECs), uniformly their composition has been in the form of a racemic mixture of Λ and Δ enantiomers. The investigation of LEECs using enantiopure iridium(III) emitters, however, remains unprecedented. Herein, we report the preparation, the crystal structures, and the optoelectronic properties of two families of cyclometalated iridium(III) complexes of the form of [(C^N)2Ir(dtBubpy)]PF6(where dtBubpy is 4,4'-di-tert-butyl-2,2'-bipyridine) in both their racemic and enantiopure configurations. LEEC devices using Λ and Δ enantiomers as well as the racemic mixture of both families have been prepared, and the device performances were tested. Importantly, different solid-state photophysical properties exist between enantiopure and racemic emitters, which are also reflected in the device performances.
authors.affiliation: Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews , St Andrews, Fife KY16 9ST, United Kingdom.
authors.forename: Diego Rota
authors.initials: DR
authors.lastname: Martir
authors.affiliation: Instituto de Ciencia Molecular, Universidad de Valencia , c/Catedrático J. Beltrán, 2, Paterna 46980, Spain.
authors.forename: Cristina
authors.initials: C
authors.lastname: Momblona
authors.affiliation: Instituto de Ciencia Molecular, Universidad de Valencia , c/Catedrático J. Beltrán, 2, Paterna 46980, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Pertegás
authors.affiliation: Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews , St Andrews, Fife KY16 9ST, United Kingdom.
authors.forename: David B
authors.identifier: http://orcid.org/0000-0002-5366-9168
authors.initials: DB
authors.lastname: Cordes
authors.affiliation: Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews , St Andrews, Fife KY16 9ST, United Kingdom.
authors.forename: Alexandra M Z
authors.initials: AM
authors.lastname: Slawin
authors.affiliation: Instituto de Ciencia Molecular, Universidad de Valencia , c/Catedrático J. Beltrán, 2, Paterna 46980, Spain.
authors.forename: Henk J
authors.initials: HJ
authors.lastname: Bolink
authors.affiliation: Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews , St Andrews, Fife KY16 9ST, United Kingdom.
authors.forename: Eli
authors.identifier: http://orcid.org/0000-0001-7183-6022
authors.initials: E
authors.lastname: Zysman-Colman
keywords: cationic iridium(III) complexes; enantiopure complexes; light-emitting electrochemical cells; photophysical properties; solid-state packing