Article

Influence of Nanomaterial Fillers in Biopolymer Electrolyte System for Squaraine-based Dye-Sensitized Solar Cells

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Abstract

The vast use of fossil fuel demands the development of new sources of renewable energy. Dye-sensitized solar cells (DSSCs) have been extensively studied due to their competitive cost, ease of fabrication, high degree of tunability and relatively good-energy conversion efficiencies. The performance and stability of DSSCs are limited by leakage and solvent evaporation. This study explores the effects of nanofillers in the performance of dye-sensitized solar cells by incorporating nano-sized titanium dioxide, iron (III) oxide and halloysite fillers into the polymer electrolytes based on κ-carrageenan/DMSO/TBAI:I 2. Optimization and characterization of various concentrations of fillers were done before incorporation in solar cells. The effect of ionic conductivity and diffusion coefficient to the overall conversion efficiency of the cells were studied. The effect of squaraine dye was also investigated. The addition of various fillers to the polymer electrolyte system increased the dissociation of iodide ions and improved the ionic conductivity of the cells. The diffusion coefficient of tri-iodide ions was also greatly enhanced because of the increased volume of the system brought about by reducing polymer-polymer interaction, which increased the mobility of the redox couple (I 3-/ I-). DSSC characterization revealed a low efficiency due to a relatively high charge transfer resistances at the TiO 2 /dye/electrolyte interface.

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... It was stipulated that even larger improvements would be attained for higher nanoparticle densities (Derkacs et al., 2006). Chan et al. (2015) investigated the effects of nanofillers in the performance of dye-sensitized solar cells by modifying polymer electrolytes with nanosized titanium dioxide, iron (III) oxide and halloysite fillers. The results showed that the incorporation of fillers resulted in increased ionic conductivity of the cells and improved dissociation of iodide ions (Chan et al., 2015). ...
... Chan et al. (2015) investigated the effects of nanofillers in the performance of dye-sensitized solar cells by modifying polymer electrolytes with nanosized titanium dioxide, iron (III) oxide and halloysite fillers. The results showed that the incorporation of fillers resulted in increased ionic conductivity of the cells and improved dissociation of iodide ions (Chan et al., 2015). However, it has been noted that the metallic nanoparticles should be encapsulated on their surfaces to prevent formation of charge traps or charge recombination sites which may lower the efficiency of the solar cells (Thomann et al., 2011;Pan & Gupta, 2012;Chan et al., 2015). ...
... The results showed that the incorporation of fillers resulted in increased ionic conductivity of the cells and improved dissociation of iodide ions (Chan et al., 2015). However, it has been noted that the metallic nanoparticles should be encapsulated on their surfaces to prevent formation of charge traps or charge recombination sites which may lower the efficiency of the solar cells (Thomann et al., 2011;Pan & Gupta, 2012;Chan et al., 2015). Zhao and coworkers' research on increased charge transfer of poly(vinylidene fluoride-co-hexafluoro propylene) (PVDF-HFP) based electrolyte by addition of graphite nanofiber (GNF) and its usefulness in dye sensitized solar cells (DSSCs) produced results that corroborated the points made above. ...
Chapter
Reliable energy systems and advances in nanotechnology together will play key role in channeling future cutting edge inventions and developments in all spheres. In this review article, the pertinence of functionalizing nanofillers and modifying nanocomposites for improved performance in various energy applications such as energy conversion, energy efficiency, energy storage, alternative energy and energy saving are expounded. This article also presents structures and unique properties of commonly used nanofillers; advances, improvement potentials and characterization of nanocomposites used in energy systems. Theoretical and experimental literature reviewed revealed that nanofillers engender improved properties in polymeric matrices. Functionalization is applicable to all types of nanofillers in use today, a number of functionalized nanofillers are already commercially available; and more extensive research is needed to achieve optimal improved results with the use of nanofillers and nanocomposites in various fields of applications.
... Although the tensile strength of the electrolyte increased considerably with the OMP -carrageenan filler, the ionic conductivity remained relatively low (1.43 × 10 − 2 mS cm − 1 ). Chan, Bantang and Camacho (2015) prepared a complexcarrageenan polymer electrolyte with TBAI and I 2 additives and TiO 2 , Fe 2 O 3 and natural halloysite nanofillers in various concentrations. The optimized concentration of the nanofillers improved the conductivity up to ∼0.35 mS cm − 1 . ...
... The open circuit voltage was 0.51 V, while the short circuit current density reached up to 7.60 mA cm − 2 with 2.06 of energy conversion efficiency. Chan et al. (2015) used polymer electrolyte consisting of -carrageenan with TBAI and I 2 additives and nanofillers as the base of the DSSC. The choice of nanofiller at an optimized concentration significantly altered the electrical performance of the DSSC. ...
Article
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In the last decade, the development of high-efficiency electrolytes based on polymeric materials has drawn increasing attention. Polysaccharides are widespread biopolymers with properties suitable for the fabrication of high-efficiency polymer electrolytes. In specific, algal-based polysaccharides are promising eco-friendly and biodegradable alternatives to conventional polymer electrolytes. This review focuses on the recent progress of polymer electrolytes based on algal polysaccharides. We set the basic consideration for high-performance polymer electrolytes and discuss the materials science aspects of algal-based polysaccharides involved. Then, we review the recent progress of algal polysaccharides-based electrolytes, including the various physical and chemical treatments applied for the enhancement of ionic conductivity and mechanical properties. Lastly, we summarize the applications of the algal polymer electrolytes in batteries, fuel cells, supercapacitors, and dye-sensitized solar cells and their performance. Algal polysaccharides are presented as biodegradable, cost-efficient, high-performance, and eco-friendly alternatives for the development of high-performance solid polymer electrolytes for modern electrochemical applications.
... Squaraine dyes are a subclass of cyanines that contain a 3-oxocyclobut-1-enolate (squarate) moiety in the polymethine chain [1][2][3]. Due to their excellent spectral characteristics such as the long-wavelength absorption and emission, high molar absorptivity, high fluorescence quantum yields, and stability, squaraines are widely used as fluorescent probes and labels for biomedical assays [4][5][6], clinical diagnostics [7,8], pharmaceutical research [9,10], as sensitive dyes in electronics [11], sensitizers for photovoltaic cells [12] and sunlight energy converters [13]. The molecular structure of these dyes was investigated using various experimental [14][15][16][17] and theoretical methods [18]. ...
... In the SqB and nor-SqB the barbituric oxygens form additional H-bonds with the methine hydrogens. Fig. 4. 1 H NMR (a,b,d) and 13 C NMR (c) spectra of norsquaraine nor-SqO in DMSO-d 6 (a) , CDCl 3 (b, c) and CDCl 3 : DMSO-d 6 1:1 (d). The intramolecular H-bonds facilitate flattening but also increase the conformational rigidity of the norsquaraine molecules (Fig. 3,a) as compared to squaraines (Fig. 3,b). ...
Article
Novel indolenine based norsquaraine dyes, wherein the oxygen of the squaric acid bridge was substituted with a barbituric or a dicyanomethylene group, were synthesized and their molecular structure, spectral and luminescent properties were compared to those of analogous squaraine dyes. The molecular structure was investigated using X-ray analysis, NMR spectroscopy and ab initio DFT B3LYP/6-311G (d, p) simulations. The calculated populations of possible conformers and the barriers of internal rotations were found to be in good agreement with the experimental data. Norsquaraines absorb and emitt light within the same long-wavelength spectral range as the corresponding squaraines but due to intramolecular H-bonds and increased conformational rigidity they were less sensitive to solvent polarity and the presence of protein (BSA).
... Moreover, gelation offers the advantage of minimizing electrolyte leakage over time, while maintaining good contact between the dye molecules and the redox mediator. Last but not least, the DSSC community can take advantage of the recent strong advances carried out in the field of polymer science and technology [73][74][75][76][77][78][79] to achieve the best performance and stability in the resulting devices. ...
... Moreover, gelation offers the advantage of minimizing electrolyte leakage over time, while maintaining good contact between the dye molecules and the redox mediator. Last but not least, the DSSC community can take advantage of the recent strong advances carried out in the field of polymer science and technology [73][74][75][76][77][78][79] to achieve the best performance and stability in the resulting devices. Spiccia and coworkers proposed cobalt-based gel electrolytes with 4 to 10 wt% of poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) incorporated in ACN [80]. ...
Article
Full-text available
Redox mediators based on cobalt complexes allowed dye-sensitized solar cells (DSCs) to achieve efficiencies exceeding 14%, thus challenging the emerging class of perovskite solar cells. Unfortunately, cobalt-based electrolytes demonstrate much lower long-term stability trends if compared to the traditional iodide/triiodide redox couple. In view of the large-scale commercialization of cobalt-based DSCs, the scientific community has recently proposed various approaches and materials to increase the stability of these devices, which comprise gelling agents, crosslinked polymeric matrices and mixtures of solvents (including water). This review summarizes the most significant advances recently focused towards this direction, also suggesting some intriguing way to fabricate third-generation cobalt-based photoelectrochemical devices stable over time.
... Thus the various inorganic/ organic nanomaterial fillers were added into the polymer matrix which improves the ionic conductivity, mechanical properties, and transport properties (Lim et al 2019). There is a limitation to adding these fillers in the polymer matrix, and it has been found that if we increase the percentage of the same filler from 1 to 3 wt% or more the conductivity of the film starts decreasing as these fillers start agglomeration and the mean free path is not available for hopping of ions (Chatzivasiloglou et al. 2007;Chan et al. 2015). The desirable conductivity can be achieved by the incorporation of two different fillers such as graphite and multi-wall carbon nanotubes (MWNTs). ...
Article
Full-text available
We investigated the use of graphite as primary filler and multi-walled carbon nanotubes (MWNTs) as secondary filler in chitosan-based polymer electrolyte film which aided in increasing the electrical conductivity of the prepared film. The addition of a small amount of MWNTs as secondary filler increased the A.C. conductivity from 2.6 × 10–4 to 1.4 × 10−3 S/cm due to the formation of conductive layers by it. The co-sensitized dye obtained from pomegranate and moss (1:1) is evaluated for the fabrication of dye-sensitized solar cells. In place of nanostructured TiO2-based photoanode, we admixed TiO2 with indium oxide (In2O3) to improve the spectral response of TiO2 for obtaining better efficiency. The use of this polymer electrolyte film along with co-sensitized natural dye and admixed photoanode helped in the fabrication of a highly efficient dye-sensitized solar cell (DSSC) with around 3.8% efficiency.
... The resulting OCV for the battery was 2.17 V. In another report, κ-carrageenan containing triiodide/iodide redox couple was modified for dye-sensitized solar cell applications with nanofillers such as TiO2, iron (III) oxide Fe2O3, and halloysite by Chan et al. [207]. For this system, the addition of various fillers to the PE system increased the dissociation of iodide ions and improved the ionic conductivity of the cells. ...
Article
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The diversification of current forms of energy storage and the reduction of fossil fuel consumption are issues of high importance for reducing environmental pollution. Zinc and magnesium are multivalent ions suitable for the development of environmentally friendly rechargeable batteries. Nanocomposite polymer electrolytes (NCPEs) are currently being researched as part of electrochemical devices because of the advantages of dispersed fillers. This article aims to review and compile the trends of different types of the latest NCPEs. It briefly summarizes the desirable properties the electrolytes should possess to be considered for later uses. The first section is devoted to NCPEs composed of poly(vinylidene Fluoride-co-Hexafluoropropylene). The second section centers its attention on discussing the electrolytes composed of poly(ethylene oxide). The third section reviews the studies of NCPEs based on different synthetic polymers. The fourth section discusses the results of electrolytes based on biopolymers. The addition of nanofillers improves both the mechanical performance and the ionic conductivity; key points to be explored in the production of batteries. These results set an essential path for upcoming studies in the field. These attempts need to be further developed to get practical applications for industry in large-scale polymer-based electrolyte batteries.
... Nevertheless presence of amino group in chitosan, sulfate in carrageenan, etheric oxygen in agarose and -OH functional group are responsible for ion migration but the crystallinity and activation energy barrier make them poor conductive (Weerasinghe et al., 2017). Besides, Biopolymers had shown tremendous long-term stability but challenged with recombination (Chan et al., 2015). Nevertheless, toxicity of the solvents inappropriate and need to research alternative ecofriendly solvents. ...
Article
Solar cells are furthermost eminent alternative solar energy conversion devices and have great potential to conquer the energy needs of the society. In recent past, Dye sensitized solar cell (DSSC) has gained a significant research interest in research community owing to physically portable nature, simple fabrication process, cus-tomizable aesthetic look and reasonable efficiency. Regardless, it still struggles for the commercialization due to its low power conversion efficiency. Since significant dye anchoring site, light harvesting efficiency through plasmon effect and scattering effect, least undesired recombination of electrons, swift electrons transportation and greater catalytic activity etc. collectively accountable for the DSSC performance and hence the DSSC structure needs to comprehend in subsystem level (Substrate, transparent conductive oxide layer, blocking layer, semiconductive oxide layer, dye, electrolyte, counter electrode) in a single platform for the revival of cell potential. This review presented an exhaustive study on substrate, transparent conductive oxide layer, blocking layer, semiconductive oxide layer, dye, electrolyte and counter electrode respectively and addressed its development with insight discussion. Furthermore, the morphological change in semiconductive oxide layer, alteration in dye pigment based on green technology for significant light absorption and potential of liquid, quasi solid and solid states electrolyte for the revival is addressed. This review also facilitates with graphical contrast to understand and envision a direction towards determinant research scope.
... Technique used to prepare polymer electrolyte is also bought into consideration for the effective performance of the DSSCs. Using simple solution casting process for preparation of polymer membrane, we have achieved higher conversion efficiency than that of a biopolymer based electrolyte [27] and a comparative (that of PVA based system [28]) efficiency of 3.62% from PVDF-HFP based electrolyte with lesser filler content (Table 2). Considering the DSSC's practical outdoor application, PVDF-HFP can overcome its solubility issues with water as compared to other two polymers. ...
Article
Fe 2 O 3 was synthesized by chemical precipitation method and used as filler in PVDF-HFP based polymer elec-trolyte for dye sensitized solar cell (DSSC) applications. The plasticized polymer membrane was developed by simple solution casting method with incorporation of Fe 2 O 3 where propylene carbonate was used as plasticizing agent. Structural confirmation of synthesized Fe 2 O 3 powder and crystallinity studies prepared polymer membrane with different weight% of Fe 2 O 3 was studied by the X-ray diffraction analysis. Fourier transform infrared studies of polymer membrane are done to study nature of polymer. Fe 2 O 3 incorporated PVDF-HFP based polymer electrolyte showed ionic conductivity of 6.36 × 10 −4 S/cm and diffusion coefficient was found to be 1.02 × 10 −6 cm 2 /s. Furthermore, the electrochemical impedance spectroscopy analysis has been done to study interfacial resistance. The prepared polymer electrolyte (2 wt% filler in PVDF-HFP based) was used in DSSC fabrication, where calculated power conversion efficiency was 3.62% with the enhancement of 2.1 times when compared to pure PVDF-HFP electrolyte. The photocurrent stability of the device under several light on-off cycles is proved via chronoamperometry study. In addition, variation of power conversion efficiencies as a function of time has also been analyzed.
... However, in the course of our investigation of electrolyte systems, we observed that it dissolves in dimethylsulfoxide (DMSO). 19,20 We investigated the solubility properties of k-carrageenan in DMSO, dissolving different amounts of the biopolymer at 60°C. A liquid solution is formed with 1 % w/v k-carrageenan (a solubility of 0.01 g/mL DMSO at room temperature and at 60°C). ...
Article
Hydrophilic polysaccharide, κ-carrageenan, was utilized as the polymer matrix in gel-electrolyte systems for dye-sensitized solar-cell (DSSC) applications. The influence of the solvent system was investigated to optimize the solubility of κ-carrageenan and tetrabutylammonium-iodide (TBAI)/I2 electrolytes by minimizing the water content because of its unfavorable effect on DSSCs. We report herein that two solvent systems, a water/acetonitrile mixed solvent and DMSO, were found to effectively dissolve the components. The composite natures of the κ-carrageenan-electrolyte systems in these solvents were confirmed with an FTIR analysis. The presence of κ-carrageenan did not impede the electrochemical properties of the electrolytes, as confirmed with cyclic voltammetry, electrochemical impedance spectroscopy and linear sweep voltammetry. The incorporation of the gel electrolytes in DSSCs showed that the DMSO system exhibited better solar-cell efficiency compared to the mixed-solvent system.
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Reliable energy systems and advances in nanotechnology together will play key role in channeling future cutting edge inventions and developments in all spheres. In this review article, the pertinence of functionalizing nanofillers and modifying nanocomposites for improved performance in various energy applications such as energy conversion, energy efficiency, energy storage, alternative energy and energy saving are expounded. This article also presents structures and unique properties of commonly used nanofillers; advances, improvement potentials and characterization of nanocomposites used in energy systems. Theoretical and experimental literature reviewed revealed that nanofillers engender improved properties in polymeric matrices. Functionalization is applicable to all types of nanofillers in use today, a number of functionalized nanofillers are already commercially available; and more extensive research is needed to achieve optimal improved results with the use of nanofillers and nanocomposites in various fields of applications.
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