Perylene dyes

C. Ego, D. Marsitzky, S. Becker, J. Zhang, A.C. Grimsdale, K. Mullen, J.D. MacKenzie, C. Silva, and R.H. Friend, Attaching perylene dyes to polyfluorene three simple, efficient methods for facile color tuning of light-emitting polymers, J. Am. Chem. Soc., 125 437-443, 2003. 

Fig. 11 One-dimensional electron density projection along the c-axis for a perylene dye intercalated in an Mg/Al LDH and a structural model based on this data. Reprinted with permission from [150]. Copyright Wiley...

Fig. 7 Bottom UVA6s absorption (left) and fluorescence spectra right) in chloroform. Blue l l-Mixture of 12b and 12c, red 12b, turquoise 12c, brown 12a, black reference of standard perylene dyes (1). Top CD spectra of 12b (red) and 12c (turquoise) in chloroform and neglible CD effect of the enantiomers 10b (orange) and 10c (green) (See also Plate 7 in the Colour Plate Section)...

Mizuguchi, J. (1997). Structural and optical properties of 5,15-diaza-6,16-dihydroxy-tetrabenzo[b,e,k,n]perylene. Dyes and Pigments, 35, 347-60. [264]... 

Compound Id behaves similarly, but the overall conversion efficiency is significantly lower, i. e. 0.022%. As a result, although no itt-conjugation between the perylene dye and the tin dioxide nanoparticles exists, electron transfer actually occurs, probably through a bridge-assisted mechanism as previously proposed for dye-excited states weakly coupled to semi-conducting particles. o On the basis of this mechanism, the lower cell efficiency found for Id-modified electrodes could be due to the longer hexylene linker in... 

Since PDAFs are wide bandgap materials, incorporation of other smaller bandgap chromophores as comonomers or substituents enables tuning of the emission colour due to efficient energy transfer from the fluorene to the other units. Random copolymers of fluorenes with other chromophores are readily prepared by the copolymerisation of the dihalochromophore with a dihalofluorene as exemplified in Scheme 9 for the synthesis of copolymers of dioctylfluorene with perylene dyes (1-5 mol%) [46,47]. 

These materials were designed so that by efficient FOrster energy transfer from the fluorene to the dye units, efficient emission across the whole visible spectrum could be obtained. Perylene dyes were chosen as the chro-... 

Such exciton trapping has been exploited by Mullen and coworkers, who prepared copolymers of dioctylfluorene- and perylene-based dyes (1-5 mol%) by Yamamoto copolymerisation (Scheme 55) [222-224]. These materials were designed so that by efficient FOrster energy transfer from the fluorene to the dye units, efficient emission across the whole visible spectrum could be obtained. Perylene dyes were chosen as the chromophores due to their high solid-state PL quantum yields, and their excellent thermal and photochemical stability. 

Due to the low mole ratio of dye units present, the above copolymers, with perylene dyes in the main chain or as end groups, show energy transfer only in the solid state. If the dyes are attached on the side chain, then copolymers containing much higher mole ratios of chromophore are accessible. The copolymer 123 (Scheme 57) in which 33% of the fluorene units have dyes attached (m n = 2 1) showed energy transfer in solution as well as in a thin film [224]. The emission colour differed slightly between the two states, with the emission maximum appearing at A,max = 561 nm in solution with a shoulder at 599 nm, and at Xmax = 599 nm in the solid state. This is probably due to interaction of the chromophores in the solid phase. 

Balraju P, Kumar M, Deol YS et al (2010) Photovoltaic performance of quasi-solid state dye sensitized solar cells based on perylene dye and modified Ti02 photo-electrode. Synth Met... 

Fig. 21 Optimized molecular structures of the perylene dyes 1 and 2. Reprinted from [252] with kind permission of Elsevier...

Persson, Thoss and co-workers later performed quantum dynamics simulations on the same perylene systems, confirming the static electronic structure picture [284]. We also reported on the same conjugated and non-conjugated perylene dyes of Fig. 21, performing TDDFT excited state calculations for the dyes adsorbed on a model Ti02 nanoparticle. 

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