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1 – 5 of 5Mozhgan Hosseinnezhad and Kamaladin Gharanjig
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…
Abstract
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.
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Zahra Ranjbar, Mozhgan Hosseinnezhad and Kamaladin Gharanjig
Hanieh Shaki, Alireza Khosravi and Kamaladin Gharanjig
In this study, two novel fluorescent dyes, based on naphthalimide derivatives have been synthesised from acenaphthene as a starting material. The ability of the dyes to graft to…
Abstract
Purpose
In this study, two novel fluorescent dyes, based on naphthalimide derivatives have been synthesised from acenaphthene as a starting material. The ability of the dyes to graft to polymer chain was then demonstrated. The novel synthesised dyes and self-coloured polymers were characterised by a variety of techniques.
Design/methodology/approach
The novel dyes were prepared through by halogenation, oxidation, imidation and amination reactions. All steps of these processes were monitored by thin layer chromatography. The fluorescent dyes and their intermediates were characterised by differential scanning calorimeter, fourier transform infrared spectroscopy (FTIR), Proton Nuclear Magnetic Resonance (1H-NMR) and carbon-13 nuclear magnetic resonance (13-CNMR) spectroscopic techniques. The molar extinction coefficients and absorption maximum wavelength were obtained by examining the dyes and polymer solutions in Dimethylformamide (DMF) and toluene solvents. The fluorescency of novel dyes and self-coloured polymers was evaluated. Their quantum yields and Stokes shift values were determined as DMF and toluene solutions. The percentage of the covalently bounded dyes into the polymer chain was calculated.
Findings
The characterisation of the synthesised dyes and self-coloured polymers verified their structural correctness. The results of reaction dyes with resin demonstrated that the dyes were covalently bonded to the chain of an acrylic polymer (resin) containing carboxylic acid groups giving self-coloured polymers. The extent of fluorescence of the synthesised dyes and their polymers showed that compounds containing functional amino group in C-4 position of naphthalimide ring have high fluorescence properties.
Originality/value
This study is original. Self-coloured polymers based on acrylic were synthesised by novel naphthalimide dyes with acrylic resin for the first time, successfully. The novel dyes and their self-coloured polymers exhibit good and acceptable fluorescent activity.
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Hooman Imani, Kamaladin Gharanjig and Zahra Ahmadi
The purpose of this study is simultaneous dyeing and mordanting of wool yarns with extracted cochineal dye and aluminum sulfate to the reduction of consuming energy, water and…
Abstract
Purpose
The purpose of this study is simultaneous dyeing and mordanting of wool yarns with extracted cochineal dye and aluminum sulfate to the reduction of consuming energy, water and time.
Design/methodology/approach
The dyeing process was optimized using the response surface methodology (RSM) approach. pH, dyeing duration and the presence of additives were chosen as variables and the color strength of samples as a response. The color characteristics and fastness attributes of samples dyed in the best condition were evaluated and compared to pre-mordant dyeing outcomes on wool yarns.
Findings
The best conditions for deep dyeing wool with cochineal dye were as follows: pH 2.5, time 110 min and the ratio of aluminum: additives 1:0 at 100 °C. Color strength of dyed wool yarns by one-bath and pre-mordant dyeing methods were approximately the same. Wool yarns can dye to the on-bath dyeing method such that the dyed samples have similar color strength and fastness properties to pre-mordant dyeing.
Social implications
Wool dyeing processes that use one-bath dyeing consume less water and produce fewer effluents. As a result, this strategy conserves water and energy for a higher quality of life. The findings of this study, in general, aid environmental protection.
Originality/value
A novel one-bath process for dyeing wool with cochineal dye at heavy depths is introduced. RSM was used to optimize the procedure and determine effective parameters on the color strength of dyed wools. Using extracted cochineal dye and aluminum sulfate in a simultaneous dyeing technique, good color fastness qualities on wool fibers were achieved.
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Kamaladin Gharanjig and Mozhgan Hosseinnezhad
The purpose of this paper is to prepare new organic dyes and use them as sensitisers in dye-sensitised solar cells. These dyes were synthesised and purified and then characterised…
Abstract
Purpose
The purpose of this paper is to prepare new organic dyes and use them as sensitisers in dye-sensitised solar cells. These dyes were synthesised and purified and then characterised by analytical techniques. Spectrophotometric evaluations of the prepared dyes were carried out in solution and on a nano-anatase TiO2 substrate to assess the possible changes in the status of the dyes in different environments. Finally, the photovoltaic properties were investigated in dye-sensitised solar cells.
Design/methodology/approach
So as to synthesise dyes, N-substituents carbazole were utilised as the fundamental electron donor group and cyanoacrylic acid or acrylic acid as electron acceptor anchoring groups. Purified dyes were dissolved in solution and coated on TiO2 substrate. Finally, dye-sensitised solar cells were fabricated to determine the photovoltaic behaviour and conversion efficiency of each individual dye.
Findings
The results showed that the dyes form j-type aggregates on the nano TiO2. The oxidation potential of synthesised carbazole dyes is > 0.2 V vs Fc/Fc+; hence, their high performance in dye-sensitised solar cells. Dye 3 exhibited 2.11 per cent of conversion efficiency in comparison to 2.89 per cent for the identical cells with Dye 9 containing cyanoacrylic acid which acted as the best acceptor group.
Practical implications
The novel dyes look as promising as highly light fast, efficient dyes for dye-sensitised solar cells.
Social implications
Organic dye provides low cost and less hazardous materials for dye-sensitised solar cells.
Originality/value
A series of new organic dyes were synthesised as sensitisers for dye-sensitised solar cells for the first time.
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