The comparison of spectra and dyeing properties of new azonaphthalimide with analogues azobenzene dyes on natural and synthetic polymers

AbstractThe aim of the present research was to prepare new acid dyes based on naphthalimides. In this respect a series of monoazo acid dyes have been obtained using 4-amino-N-methyl (alternatively N-butyl)-1,8-naphthalimide, aniline and p-nitroaniline as diazo components. 2-Naphthol-6-sulfonic acid (Schaeffer’s acid) and 1-naphthol-8-amino-3,6-disulfonic acid (H-acid) were used as coupling components. The spectrophotometric properties of the synthesized dyes were investigated in various solvents and compared with analogues azobenzene dyes. It is found, when acid dyes are applied in various solvents and different pH, additional bathochromically shifted bands of different intensity appear in the electronic spectra. This effect is caused by the occurrence of the equilibrium of azo and hydrazone forms in the dyes. The synthesized acid dyes were applied on wool fabrics in order to consider their dyeing properties, fastnesses and the obtainable color gamut. The synthesized dyes represented that they have the ability of dyeing wool and polyamide fabrics and give red to violet hues with good wash, medium light, and good milling and perspiration fastnesses

Low turn-on voltage of doped organic light emitting diodes based on food dyes

Three derivatives of food azo dye were investigated (Dyes 1, 2 and 4) by theoretical and experimental tools. Photophysical properties, based on theoretical estimations, experimental evaluations, electrochemical and photoelectrical properties were discussed. The compounds exhibited efficient emission of solid state with maximum fluorescence intensity at the range of 517–646 nm and PLQY (photoluminescence quantum yield) values at the range of 9–17% in non-doped solid state and 13–39% in doped solid state. In this study 90 wt percent of PBD (2-(4-tert-Butylphenyl)-5-(4-biphenylyl)-1,3,4-oxadiazole) have been used as the electron transporting host who derived balanced charge carrier transport for high internal and external efficiency of OLEDs (organic light emitting diodes). Ionization potential for compounds was found to be comparable (5.85 and 6.18 eV) by photoelectron emission spectrometry. According to the fabrication of devices for gaining charge mobility the layers of the dyes showed properties as a bipolar charge transporting with balanced hole and electron mobility and the values reaching to 1.27 × 10−4 cm2/Vs and 1.09 × 10−4 cm2/Vs respectively at high electric fields. Furthermore, OLEDs consist of azo dyes as an emitter layer fabricated by PVD (physical evaporation deposition) method and the maximum values of the best device showed, consist of, the low turn on voltage of 2.69 V and values of brightness, current efficiency, power efficiency, EQE (external quantum efficiency) 16432.40 cd/m2, 8.20 cd/A, 6.95 lm/w, 4.89% respectively

Synthesis and Characterization of Two New Organic Dyes for Dye-Sensitized Solar Cells

<div><p></p><p>In the present study, two new organic dyes based on indigo were prepared and used as sensitizers in dye-sensitized solar cells. To this end, indoxyl was utilized as the electron-donor and acrylic acid and cyanoacrylic acid were used as the electron-acceptor anchoring groups. These dyes were purified and characterized by analytical techniques. Spectrophotometric evaluations of the prepared dyes in solution and on a nano-anatase-TiO₂ substrate were investigated. Additionally, oxidation potential measurements were also carried out. Finally, dye-sensitized solar cells were fabricated to determine the photovoltaic behavior and conversion efficiency of each dye.</p> <p>[Supplementary materials are available for this article. Go to the publisher's online edition of <i>Synthetic Communications®</i> for the following free supplemental resource(s): Full experimental and spectral details.]</p> </div

Substitution of metal ion mordant with biomordants: Effect on color and fastness of reseda dyed on wool yarns

The environmental production of handmade carpets considering the application of natural materials; fibers, dyes, and mordants helps us benefit from the advantages of using renewable sources of raw materials. Metal salts are frequently employed as mordants to improve the fastness qualities. This article aims to investigate the yellow appearance of handmade carpets achieved by applying biomordants instead of metallic ones through spectral and colorimetric analysis. This method involved using reseda as a natural dye, yellow and black myrobalan as biomordants, and alum as a metallic mordant. After pre-mordanting and dyeing of the wool yarns, the achieved colors, color strengths, and key fastness properties were compared. The findings showed that using biomordants leads to appropriate color strengths and fastness qualities in addition to expanding the color gamut. Gratefully, the outcomes of current research guarantee to achieve the yellow appearance in Iranian handmade carpets through totally the novel eco-friendly procedure.</p

Nanocomposite Based on HA/PVTMS/Cl2FeH8O4 as a Gas and Temperature Sensor

In this paper, a novel nanocrystalline composite material of hydroxyapatite (HA)/polyvinyltrimethoxysilane (PVTMS)/iron(II)chloride tetrahydrate (Cl2FeH8-O4) with hexagonal structure is proposed for the fabrication of a gas/temperature sensor. Taking into account the sensitivity of HA to high temperatures, to prevent the collapse and breakdown of bonds and the leakage of volatiles without damaging the composite structure, a freeze-drying machine is designed and fabricated. X-ray diffraction, FTIR, SEM, EDAX, TEM, absorption and photoluminescence analyses of composite are studied. XRD is used to confirm the material structure and the crystallite size of the composite is calculated by the Monshi&ndash;Scherrer method, and a value of 81.60 &plusmn; 0.06 nm is obtained. The influence of the oxygen environment on the absorption and photoluminescence measurements of the composite and the influence of vaporized ethanol, N2 and CO on the SiO2/composite/Ag sensor device are investigated. The sensor with a 30 nm-thick layer of composite shows the highest response to vaporized ethanol, N2 and ambient CO. Overall, the composite and sensor exhibit a good selectivity to oxygen, vaporized ethanol, N2 and CO environments