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In the first part of this work we presented the synthesis and photophysical properties of a series of transition metal donor-acceptor Ir(III)complexes of the type [(C^N)2Ir(N^N)][PF6]. The Ir(III) was connected with hole conducting donor-moieties like carbazole (CZ) and triarylamine (TAA) linked via a methylene and ethylene bridge to the cyclometalating C^N ligands phenylpyrazole (ppz) and phenylpyridine (ppy). Bidentate N^N and P^P ligands like 2,2’-bipyridyl (bpy), 3,4,7,8-tetramethyl-1,10-phenanthroline (tmp) and cis-1,2-bis(diphenylphosphino)ethylene (bdppe) were used as acceptor units. In order to analyse the influence of the electron density of the bpy ligand, TAA-complexes with acceptor- and donor-substituted bpy acceptor units were synthesised. Therefore, 4,4’-dinitro-2,2’-bipyridyl, 4,4’-dichloro-2,2’-bipyridyl, 4,4’-dimethoxy-2,2’-bipyridyl and 4,4’-dimethylamino-2,2’bipyridyl were used as neutral N^N ligands. In order to compare the photophysical properties, all reference compounds without hole conducting component were syntesised. All the carbazole compounds, except the bdppe complexes, exhibit emission and transient absorption properties similar to their reference compounds that make them interesting for OLED (organic light emitting device) applications. LEC (light emitting electrochemical cell) studies show a red shifted luminescence. The triarylamine compounds do not luminesce at RT but they exhibit an intense, blue-shifted and long-lived luminescence at 77 K in a rigid matrix. The transient absorption spectra differ strongly from that of their reference compounds. The spectra display characteristic features of the spectra of the isolated radical anions and cations supported by spectroelectrochemical measurements. Thus, it can be assumed that the transient states are charge separated (CS) states in which the positive charge is localised at the TAA donor units and the negative charge at the N^N acceptor units. The decays of the transient states are biexponentially what indicates the presence of two transient states, the 1CS and the 3CS state. To understand this behaviour the differently substituted bipyridyl-complexes were synthesised and analysed. Temperature dependent transient absorption measurements showed that all rate constants are indepentend of the temperature, except for the complex with OMe subsituents at the bpy ligand. The equilibrium constant K = k1 / k2 is nearly one for all complexes. For the OMe-compound it decreases with increasing temperature. Plotting the rate constants vs. the free energy differences (determined by cyclovoltammetry measurements) shows that all constants are decreasing with increasing donor strength of the bpy ligand. DFT calculations on the OMe-compound are already in work. In the second part of this work, neutral Ir(III) and Pt(II) complexes of the type [(O^O)Ir(N^N)2] and [(O^O)Pt(N^N)] were introduced. There, TTA was connected directly or via a CH2 bridge to acectylacetonate (acac = O^O) in order to probe the influence of the different kinds of connection on the photophysics of the complexes. As the bidentate N^N ligand 2,2’-bipyridyl (bpy) was chosen. All the corresponding reference compounds without triarylamine were obtained in order to compare with the TAA substituted analoga. Furthermore, the homoleptic fac Ir(N^N)3 complex with triarylamine connected via a methylene and ethylene bridge to phenylpyrazole as introduced in the first part of this work was synthesised. The synthesis of the Ir(III) compound with the TAA substituted acac ligand connected via the CH2 group was not successful. All the neutral triarylamine-substituted -diketonato Pt(II) and Ir(III) complexes do not luminesce at RT, except the Pt(II)-complex with CH2 bridge. This compound shows transient state characteristics that are in good agreement with the luminescence lifetimes at RT and that are similar to the reference compound, what suggests to a 3Pt(N^N)(O^O) state. The complexes without the CH2 bridging unit show no transient signals what may be caused by charge-transfer quenching due to the direct linkage between donor and acceptor unit. The homoleptic fac Ir(N^N)3 complex exhibits no emission at RT and no transient signals. At 77 K it shows a highly structured emission with 14 s lifetime. Compared to the literature-known reference compound this emission is caused by the population of a 3Ir(ppz)3 state. Our findings are important for designing complexes with stronger acceptor units (i.e. naphthaleneimide) for long CS states lifetimes to be used as photosynthesisers in solar cells and other optoelectronic devices. Besides, LEC and OLED studies on the carbazole complexes are still of interest to analyse the degree of triplet-triplet-annihiliation in these devices.