Functional ruthenium(ii)- and iridium(iii)-containing polymers for potential electro-optical applications

Abstract

The need for novel materials with luminescent properties and advanced processing features requires reliable and reproducible synthetic routes for the design of suitable materials, such as e.g. polypyridyl ruthenium(II) and iridium(III)-containing polymers. The most popular ligand for those purposes is the 4,4'-functionalized bipyridine unit. Therefore, several synthetic strategies for the derivatization of the 4,4'-dimethyl-2,2'-bipyridine are highlighted, and in particular functionalities, which enable further covalent linkage to polymeric structures, are discussed in this critical review. Subsequently, the different synthetic strategies for the preparation of polymeric metal-complexes are described, either starting from small functionalized complexes (later covalently attached to the polymer), or from macroligands (subsequently coordinated to the metal ions). The designed materials reveal good processing properties using spin coating and inkjet printing, as well as beneficial electro-optical properties for potential thin functional film applications, such as light-emitting electrochemical cells.

Recent Developments in the Application of Phosphorescent Iridium(III) Complex Systems

“…Therefore, the design of (co)polymers, combining different functions (charge transport www.advmat.de and emission), has received increasing attention. [11,113,114] The expected benefits are better energy transfer to the emitters (and thus higher efficiencies) and higher durability of the device. In addition, polymeric materials are of special interest, with respect to their flexibility, film-forming properties, and processability from solution, e.g., by inkjet printing.…”

“…Two advantages over the conventional polymer-based LECs are prominent: i) no additional ionconducting material is required since the transition metal complexes are intrinsically ionic and ii) higher electroluminescence efficiencies are reachable due to the phosphorescent nature of the complexes. [227] Apart from the intensively studied LECs based on [Ru(bpy) 3 ] 2þ and closely related complexes, [1,11,225,230] iridium(III)-based complexes have turned out to be highly promising candidates for LEC devices due to their high quantum efficiencies. [9,[77][78][79][80][231][232][233][234] As a highlight in this respect, the green-emitting complex [(ppy-F 2 ) 2 Ir( t Bu 2 -bpy)](PF 6 ) (Scheme 2) should be mentioned.…”

Polymer‐Fullerene Bulk‐Heterojunction Solar Cells

“…[82][83][84][85] The metal atom integrated into the polymer backbone can increase the mixing of the first excited singlet and triplet states, leading to higher electroluminescence quantum efficiencies of PLEDs. In contrast, metallated conjugated polymers have rarely been tested as donor materials in bulk-heterojunction solar cells.…”

Polymers that Contain Ligated Metals in their Side Chain: Building a Foundation for Functional Materials in Opto‐Electronic Applications with an Emphasis on Lanthanide Ions

“…A number of groups have studied the solution behavior of polymers that contain Ir III complexes. Schubert studied a variety of backbones [27][28][29][30][31] that contained Ir III complexes including poly(ethylene glycol) (PEG), polystyrene (PS), and poly(e-caprolactone) (PCL), Weck reported a number of poly(norbornenes) that contained Ir III complexed with bipyridine and phenyl-pyridine ligands, [32,33] while Tew reported block copolymers based on PS and terpy-modified acrylamides that contained Ir III confined to one block. [34] Much of this work has focused on establishing synthetic methods to produce a variety of new metal-containing polymers that are well characterized.…”