Reducing global pollution and the rising temperature caused by fossil fuel consumption is not a trivial. The paint, colorants and coatings industry is one of the industries that pollute the ...environment, and attention and research are very important to reduce pollutants in this field. In this congress, we were honored to host numerous international scientists in color and coating (11 keynote lecturers, 37 invited speakers, and 20 regular talks from 5 continents and 17 countries) to present their latest research activities. 140 poster contributions from over 300 participants were presented during the congress.
•Applied Artificial Intelligence approach in design of dye sensitized solar cells.•Explored interdependence between construction parameters with cell performance.•Predicted stochastically power ...conversion efficiency and durability of DSSCs.•Found conditions required to maximize both conversion efficiency and durability.•Realized DSSCs proposed by the model with maximum possible characteristics.
Application of mixture of dyes is a simple at the same time efficient approach to enhance the performance of dye-sensitized solar cells. The superior conversion efficiency achieved by mixture dyes is attributed to the broader light harvesting. Nevertheless, it has been realized that keeping both power conversion efficiency (η) and durability (D) of dye-sensitized solar cells (DSSCs) with two dyes is a very difficult task. Artificial neural network (ANN) and genetic algorithms (GA) approaches were blended to modeling, optimization, and simultaneous maximization of η and D in terms of assembling parameters of DSSCs. The interdependence between input parameters (volume ratio of organic dyes, concentration of anti-aggregation agent, and temperature) and outputs (η and D) was uncovered with the aid of ANN-based computer code developed in this work. A general map was accordingly given for the production of DSSCs with possible maximum η and D. The best assembling parameters were then suggested by the GA algorithm and applied in manufacture of solar cells, where an exceptional agreement between model outputs and experiments was achieved. Typical cells with maximum conversion and durability revealed η and D in the range of (7.17–7.28) and (1700–2000h), respectively.
Purpose
The purpose of this paper is to study assembling parameters in dye-sensitised solar cells (DSSCs) performance. For this end, 3a,7a-dihydroxy-5ß-cholanic acid (cheno) are selected as ...anti-aggregation agent and two solutions, namely, tetrabutyl ammonium iodide and (PMII)IL used as electrolyte.
Design/methodology/approach
A series of organic dyes were selected using N-substituents carbazole as electron donor group and acrylic acid and cyanoacrylic acid as electron acceptor groups. Absorption properties of purified dyes were studied in solution and on photoelectrode substrate. DSSCs were prepared in the presence of anti-aggregation agent and different electrolyte to determine the photovoltaic performance of each dyes.
Findings
The results showed that all organic dyes form J-aggregation on the photoanode substrate in the absence of anti-aggregation agent and the amounts of aggregation were reduced in the presence of anti-aggregation agent. DSSCs were fabricated in the presence of anti-aggregation agent. The photovoltaic properties were improved using tetrabutyl ammonium iodide as electrolyte. The maximum power conversion efficiency was achieved for D12 in the presence of cheno and tetrabutyl ammonium iodide as anti-aggregation agent and electrolyte, respectively.
Social implications
Organic dye attracts more and more attention due to low cost, facile route synthesis and less hazardous.
Originality/value
The effect of anti-aggregation agent and electrolyte on DSSCs performance was investigated for the first time.
Due to population growth and subsequent growing energy demand, clean energy generation is one of the major challenges today and in the future. Dye-sensitized solar cells (DSSCs) is one of the new ...approaches to producing clean, endless energy. In this review, the primary function, structure, performance parameters, and key elements of DSSCs are analyzed first, with a focus on the photosensitizer as the crucial part due to electron production. Photosensitizers based on natural resources recently attracted attention because of their economic and environmental advantages, but there are substantial challenges such as low conversion efficiency and long term stability. Also, diverse and, in some cases, contradictory results presented in the literature make conclusions difficult. Here, different challenges about DSSCs based on natural dyes are categorized and discussed according to the published papers, and possible solutions are presented, which could shed light on future investigations. Furthermore, according to different factors, such as average solar radiation and economic/technological aspects, DSSCs based on natural dyes are proposed to be the most promising renewable energy technology for arid to semi-arid, sunny countries like Iran in the future. Accordingly, the performance of DSSCs based on natural dyes manufactured using dye extract of different plants grow in Iranian is summarized then. In recent years, many DSSCs based on natural dyes have been manufactured using different plants grown in different parts of the country. Interestingly, it is possible to extract many natural dyes for DSSCs based on natural dyes from agricultural wastes such as saffron petals and walnut shells, of which thousand tons them are disposed every year.
The complexation mechanism of zedo gum and cress seed gum as nutraceutical polysaccharides with gelatin (type-A and type-B) was investigated as a function of pH, Protein to polysaccharide mixing ...ratio and ionic strength. Turbidity measurements were performed to achieve optimum reaction conditions. Furthermore, Zeta potential measurements along with measuring complex coacervation yield were carried out to support the turbidity results. The state diagrams representing complex coacervation formation limits were obtained for each system. FTIR analysis was performed on resulted complex coacervates which confirmed the molecular interactions between each gum and gelatin. Also, the coacervate phase of the suspensions showed shear-thinning behavior according to steady-state flows and represented higher values of storage moduli at lower frequencies in frequency sweep measurements. All systems which are assessed in this study have the potential to form particles, however, the one containing gelatin type-A had better performance in terms of pH stability.
•Complex coacervates were formed using zedo gum and Cress seed gum as a polysaccharide source and gelatin.•The best gum:gelatin mixing ratio of complex coacervates prepared by zedo gum, cress seed gum and gelatin were evaluated.•The optimum pH of complex coacervates prepared by zedo gum, cress seed gum and gelatin were determined.•Wider pH window of complex coacervation was observed for systems containing Gelatin type-A.•Increasing ionic strength shrank the pH window of complex coacervation.•All complex coacervates had pseudoplastic behavior.
Enhanced thermal stability of anthocyanins from black barberry was obtained using an optimum concentration of Angum gum (AG) and cress seed gum (CSG). To this goal initially, the phytochemical ...characteristics, and the thermal stability of purified and non‐purified anthocyanins were investigated to perceive the effect of the purification process. Then the effect of each gum and its concentration was evaluated on the thermal degradation kinetics of anthocyanins. Results demonstrated that both gums enhanced the thermal stability of anthocyanins, while CSG had a superior effect. Findings also revealed that the half‐life of anthocyanin was increased at 60°C from 366 ± 22.8 to 432 ± 4.2 and 636 ± 52.8 min in presence of AG and CSG, respectively. TGA results confirmed that the presence of SF‐AG and CSG in their optimum concentration enhanced the heat stability of anthocyanin extract. Also, physical molecular bondings were confirmed by the FTIR spectrums where some peaks attributed to both of the extract and the gums were shifted. Plateau or flake‐like micro‐particles were detected by SEM which correspond with the most freeze‐dried microcapsules.
Practical Application
The results of this study may contribute to the enhanced thermal stability of anthocyanins from barberry that can be used as a coloring agent in beverage and food systems. Moreover, it can be used in preparation of natural nutraceuticals and pharmaceuticals.
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•AIE persulfurated benzene derivatives were designed and synthesized.•The crystallite size was reached to be 100.07 nm.•The temperature dependence of the carrier mobility at 298 K and ...77 K was studied.•A higher value of hole mobility of 7.50 × 10-4cm2Vs was obtained at an electric field of 900 V0.5cm0.5.
In this research, two persulfurated benzene molecules consisting of amine and carboxylic acid derivatives were designed, synthesized and the effect of substitution in para position on absorption, fluorescence, and aggregation induced emission (AIE) were investigated. Moreover, taking into account the simpler method, the space charge limited current (SCLC) was considered and the temperature dependence on carrier mobility (μ) of the derivatives was investigated. The maximum value of hole mobility (μh) at 298 K was calculated to be 7.50 × 10-4cm2Vs at an electric field of 900 V0.5cm0.5. Since the crystallite size of the compound consisting of the NH2 group was higher (100.07 nm), the (μ) at 298 K and 77 K were also higher than the other counterpart. As a result, the NH2 substitution played a more effective role in increasing the (μ).
New Ru-dyes were designed with indoline and thioindigo groups for dye-sensitized solar cells (DSSCs). Thioindigo was used as an effective substitute for improving fastness properties, and the ...synthesis efficiency of dyes 1 and 2 was 78 and 82 %, respectively. Cyanoacrylic acid is a suitable electron-withdrawing group in the preparation of photosensitizers, which improved the conversion efficiency by about 88 % in this research. The optical response of the complexes was evaluated theoretically and experimentally. The presence of cyano groups effectively bonds with the semiconductor layer, resulting in a better photovoltaic response. Furthermore, the prepared complexes have two types of electron withdrawing groups, carboxylic acid and cyanoacrylic acid, which yield 3.29 % and 6.23 % efficiency, respectively. In addition, co-sensitization using two prepared complexes and N719 was studied and analyzed. The efficiency of DSSCs prepared with N719 and complexes 1 and 2 was 8.10 and 9.49 %, respectively.
•Thioindigo substituent used in photosensitizer's preparation based on Ru-complex.•Two continuous reactions, substitution and condensation, were used for the synthesis of dyes.•DSSCs were sensitized with individual and co-sensitized method.•Individual DSSCs based on Dye 1 and 2 showed efficiency of 3.29 and 6.023 %, respectively.•The efficiency of DSSCs prepared with N719 and complex 1 and 2 were 8.10 and 9.49 %, respectively.
To reduce environmental pollution, it is essential to use green processes in dyeing and meet its requirements. Most natural dyes have a low affinity to be used in the dyeing process. To refine this ...limitation, the mordanting flow is necessary for many dyeing cases. Pumpkin extract as a natural, metal-rich source can be used as a bio-mordant in green dyeing of natural yarns such as wool. Two natural dyes native to Iran,
Reseda luteola
and madder, were employed in this study. The effectiveness of bio-mordant presence on yarns was evaluated by FTIR-ATR test from mordanted and mordanted-dyed wool samples. The study of
K
/
S
(color strength) content of dyed samples showed that increasing the dye concentration increases the amount of
K
/
S
. Fastness performance of wool dyed with pumpkin alternated from good to excellent depending on natural dye type and concentration, due to the formation of complex structures.
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