- Y-shape structured azo dyes with self-transforming feature to zwitterionic form as sensitizer for DSSC and DFT investigation of their photophysical and charge transfer properties
-
Two novel azo dyes with D-π-A-π-D structures were designed and synthesized to investigate the relationship between molecular structure and sensitizing performance on applying for dye-sensitized solar cells (DSSCs) in comparison with their linear counterparts. Introducing hydroxyl auxiliary groups and arranging π-conjugation length as two parallel and series structural architectures, Y-shape and linear, led to red shift in absorption wavelength and increase in absorption intensity for the Y-shape pattern providing an efficient charge transfer pathway and improved Jsc and η of the DSSCs. Emerging a zwitterionic form, azonium structure, of the sensitizer in parallel configuration for the dyes 1a.p and 1b.p, enhanced light absorption domain and changed anchoring fashion could engendering improved electronic overlapping. The easily–synthesized dyes were evaluated for photophysical and electrochemical properties and turned out that the parallel-decorated dyes displayed better results than the series types as photosensitizers for DSSCs. ATR and Raman spectra clearly showed the adsorption of these dyes on the TiO2 surface. Operational tests of DSSCs, coated by titled azo dyes, illustrated that decorating π-conjugation pattern as parallel structure as well as accessorizing the donor unit with hydroxyl groups improved the photovoltaic performance. Optimized band gap due to participating the azonium structure and restricted electron recombination as well as rectified dye regeneration were proposed as main elements in enhancing performance parameters. A higher solar conversion efficiency was recorded for DSSCs based on the Y-shape dyes compared to other meta azo dye-based cells that were previously reported. Computational calculations were used to corroborate the opto-electrochemical traits of the dyes with a special concern on the influence of structural pattern on photovoltaic features.
- Alizadeh, Taher,Esrafili, Mehdi D.,Noruzi, Shima,Seyednoruziyan, Bahareh,Shamkhali, Amir Nasser,Zamanloo, Mohammad R.
-
-
- Oxidative hair dye compositions
-
Oxidative hair dye composition containing as "para component" compounds of the formula: SPC1 Or their acid addition salts, in which: R1 is alkyl or hydroxyalkyl; R2 is hydrogen or hydroxyalkyl; R3 is hydrogen, alkyl, alkoxy or halogen; and R4 occupies any one of the remaining positions on the benzene radical and is hydrogen, alkyl, alkoxy or halogen; providing that R2 is hydrogen when R3 is alkyl, alkoxy or halogen and providing that at least two of R1, R2, R3 or R4 are other than hydrogen.
- -
-
-