Textile and dyeing are one of the most significant industries in many states. The employing of natural dyes in dyeing procedure is very important due to the environmental security of the area. To ...obtain a green, clean, and environmentally friendly dyeing of yarns, two natural dyes of madder and weld, which are native to Iran, were employed for dyeing yarns for carpet preparation. Due to the low affinity of natural dyes and maintaining the biocompatibility of the dyeing process, the oak was used as a new tannin rich mordant. The ultrasound-microwave-assisted method in water solution was used for extraction, and yield to the process was obtained about 27, 32, and 36% for madder, weld, and oak, respectively. The extractions were analyzed by UV–Visible and SEM techniques, and the ash, humidity, and density properties of these were investigated. The pre-mordanting method was employed for this study, and ferrous sulphate was used for compare of natural mordant performance. The washed, mordanted, and dyed yarns were investigated by analytical techniques, and the accuracy of these processes was confirmed. The fastness properties as well as the colorimetric characteristics of dyed yarns were assessed using related standards, and the dyed yarns have acceptable performance and could compete with metal mordant, colorimetrically.
The present study aims to extract a natural reddish brown colorant from Peepal (
Ficus religiosa
) for silk dyeing using the microwave radiation process (MW). The colorant was isolated in aqueous and ...acidic media, and MW treatment for 1, 2, 3, 4, and 5 min has been given to both fabric and extract to observe changes in color intensity. The dye variables have been optimized, and for sustainable shade making process with good fastness, 1.0–5.0 g/100 mL of sustainable chemical and bio-mordants has been employed. It has been found that after microwave treatment for 3 min, under selected conditions, the irradiated aqueous extract has given high color intensity onto silk fabric. The utilization of 3% of Al, 4% of Fe, and 2% of tannic acid (T.A.) as pre chemical mordant whereas 4% of Al, 4% of Fe, and 3% of tannic acid as post chemical mordant have given good color characteristics. In comparison, 4% of acacia and 3% of turmeric and pomegranate while 3% of acacia and turmeric and 4% of pomegranate extracts as post-bio-mordant have given excellent color characteristics. It is concluded that MW treatment has an excellent sustainable efficacy to isolate colorant from Peepal bark for silk dyeing, whereas the inclusion of bio-mordants has not only made the process more sustainable and environmental friendly but also best K/S, and
L*a*b*
values have been acquired.
Nowadays, using sustainable dyeing process has become a necessity, but does not meet performance requirements. Application of biomordants was recommended to enhance the quality of dyeing. ...Tannin-based biomordants appeared advantageous in green dyeing; meanwhile, unconditional affinity towards fibers of different types has attracted the attention of researchers. We introduce the idea of using combination of natural mordant as a new technique for sustainable dyeing of wool and a model natural fiber. In this study, Iranian madder was used as green dye and Yellow Myrobalan (YM) and Black Myrobalan (BM) employed as biomordant. FTIR-ATR spectra of the washed, mordanted, and mordanted-dyed wool fibers confirmed appropriate bonding among wool fibers, green mordant, and dye molecules. The superior color strength of wool fibers dyed with 4 %YM+6 %BM and 40 % madder was featured by
K/S
value of 35.77 and was obviously higher than that of madder by sumac, 9.5. Fastness properties (light, wash, and rub fastness) of wool dyed with combination of YM and BM were good.
Two new metal-free organic dyes with D–A–π–A structure containing monotriphenylamine as electron donor and cyanoacrylic acid as end electron acceptor were prepared. All intermediates and organic ...photosensitizers were specified by analytical techniques. The cyclic voltammetry analysis was employed to examine the possibility of applying organic dyes in dye-sensitized solar cells and the results show that the charge transfer overall is done thermodynamically. Three configurations as individual, co-sensitization and tandem were selected for the investigation of photovoltaic properties. The photovoltaic investigation shows efficiency of 3.84%, 5.61%, 7.74% and 8.69% for Dye 1, Dye 2, co-sensitization and tandem structure, respectively.
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–Scherrer method, and a value of 81.60 ± 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.
Reducing pollution in various industries such as textile is very important. In this study, the important approach was selected to reduce the pollution of dyeing process's pollution, namely the ...selection of plant-based dyes and mordants. The dyes and mordants were extracted from ultrasonic media to obtain maximum efficiency with the least pollution. The extraction efficiency of madder, Reseda, and walnut husk in water with the ultrasound-assisted method was 23%, 33%, and 36%, respectively. The pre-mordanting method was used for mordanting, and to compare the results, Fe (ferrous) salt was selected as the mineral mordant. FTIR (Fourier Transform Infrared Spectroscopy) as analysis techniques were employed to investigate the extracts obtained and the changes in the fibers. The study of K/S (color strength) content of dyed samples showed that increasing the dye concentration of the dye increases the amount of K/S. The colorfastness properties of all samples were investigated using the ISO (International Organization for Standardization) standards. The wash, light, and rub fastness of dyed yarns were good, moderate, and good, respectively.
Reducing pollution in various industries such as textile is very important. In this paper, two parallel methods were used to reduce pollution of the process and application of dye. The first approach ...was the selection of plant-based dyes (Madder with the botanical name of Rubia tinctorum and Reseda with botanical name of Reseda odorata) and the application of a tannin-based mordant (pomegranate peel with botanical name of Punica granatum). The second approach was extraction and dyeing in ultrasound media. The extraction efficiency of madder, Reseda, and pomegranate peel in water with the ultrasound-assisted method was 23%, 33%, and 29%, respectively. In this paper, the meta-mordanting method was used for mordanting procedure, and to compare the results, Cu (copper) was selected as the mineral mordant. Extracts were identified by FTIR method. Yarns’ changes in the process of mordanting and dyeing are investigated using two methods, FTIR and SEM. The effect of changing the concentration of mordant and dyes with the amount of K/S were evaluated and the K/S value of dyed samples illustrated that increasing the dye concentration of the dye increases the amount of K/S. The color fastness properties of all samples were investigated using the ISO standards.
Tandem solar cells were developed for improved efficiency in connection with perovskite solar cells and dye-sensitized solar cells. The organic dye based on thioindigo and N719 were applied in ...fabricating dye-sensitized solar cells as photosensitizers. We achieved an 8.77% and 10.54% efficiency tandem solar cell formed by a top perovskite solar cell and dye-sensitized solar cells based on organic dye and N719 for the bottom cell, respectively. The photovoltage of tandem solar cells was reported about 1.1 V, but the photocurrent was limited by the dye-sensitized solar cells and was about 12.8 mAcm
−2
.
Corrosion is a harmful processes which by definition is a chemical or electrochemical reaction between a substance (usually a metal) and the environment which leads to a change in the properties of ...the substance and has destructive effects. In this study, new composites consisting of Al/WS2/ZnTerp-2TH with 5 and 10 wt.% ZnTerp-2TH were prepared and the results were fully compared. Al/WS2 played the role of matrix and ZnTerp-2TH played the role of reinforcement. In other words, as a novelty to prevent the corrosion of Al/WS2, ZnTerp-2TH is designed and synthesized and showed good results when the corrosion ratio was reduced by the existence of ZnTerp-2TH. Furthermore, the NMR and mass analysis of ZnTerp-2TH were carried out, and the thermal properties, X-ray diffraction, Fourier-transform infrared (FTIR) spectroscopy, morphology, energy-dispersive X-ray spectroscopy (EDX) analysis and corrosion behavior of the composites were also discussed in detail. The crystal size values of composites were calculated by the modified Scherrer method 34, 26 and 27 nm for Al/WS2, Al/WS2/5 wt.% ZnTerp-2TH and Al/WS2/10 wt.% ZnTerp-2TH, respectively. The microstructural examination of the specimens showed that the reinforcing phase (ZnTerp-2TH) has a favorable distribution on the surface of Al/WS2 when it covers the cracks and holes. In addition, the corrosion investigation results showed that the addition of ZnTerp-2TH to Al/WS2 can improve the corrosion resistance when the Ecorr and Icorr values of Al/WS2/10 wt.% ZnTerp-2TH were recorded in tandem −724 mV/decade and 5 uA cm−2.
Photovoltaic systems, such as dye-sensitized solar cells (DSSCs), are one of the useful tools for generating renewable and green energy. To develop this technology, obstacles such as cost and the use ...of expensive compounds must be overcome. Here, we employed a new MoS2/graphene hybrid or composite instead of platinum in the DSSCs. Furthermore, the correctness of the preparation of the MoS2/graphene hybrid or composite was evaluated by field emission scanning electron microscope (FESEM), and the results showed that the desired compound was synthesized correctly. Inexpensive organic dyes were used to prepare the DSSCs, and their chemical structure was investigated by density functional theory (DFT) and cyclic voltammetry (CV). Finally, the DSSCs were fabricated using MoS2/graphene composite or hybrid, and to compare the results, the DSSCs were also prepared using platinum. Under the same conditions, the DSSCs with MoS2/graphene composite illustrated better efficiency than MoS2/graphene hybrid or/and graphene.
