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Abstract 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, customizable 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.

Abstract A newly designed back contact dye-sensitized solar cells (BCDSSC) with back contact electrode (BCE) of Ti for electron collection, is placed on the side opposite to side of light irradiation on TiO2 with synthesized organic compound doped poly (ethylene oxide)/poly (vinylidene fluoride)/potassium iodide/Iodine polymer electrolyte was introduced for the application of solar energy to electric energy conversion. The surface morphology of the polymer electrolyte study was carried out by SEM, XRD, DSC, DTA, TGA and it proves that the synthesized organic compounds enhances the amorphous nature of the polymer due to well coordinate with redox couple. The movement of I−/I3− characterized with UV–vis spectroscopy proves of organic compound with Iodine in the redox couple to decrease the sublimation of iodine. The conductivity of polymer/potassium iodide/iodine/organic compound shows high conductivity of 4.9 × 10−4 S cm−1 and it confirms that the importance of synthesized organic compounds in polymer electrolyte. The TiO2/Ti (BCE)/N3dye/PEO/PVdF/Potassium iodide/Iodine/PDSD/Pt compounds yielded an efficiency of 8.9% under illumination of 70 mW cm−2 at A.M. 1.5.

Abstract Cadmium selenide (CdSe) nanoparticles were synthesized in aqueous medium using mercaptopropionic acid (MPA) as the stabilizer at the temperature 100 °C. Air stable sodium selenite (Na2SeO3) was used as the selenium source. The synthesized particles were used to co-sensitize the TiO2 nanotubes with N3 dye. Ex-situ linker assisted method was used to sensitize the nanotubes by CdSe nanoparticles. Electrochemical anodization technique was employed to prepare TiO2 nanotubes in the presence of hydrogen fluoride (HF) as electrolyte. A solar cell was fabricated using co-sensitized TiO2 nanotubes by N3 dye/CdSe nanoparticles as the anode and platinum coated fluorine doped tin oxide (FTO) electrode as the cathode. Polysulphide ( S 2 - / S x 2 - ) mixture was used as the electrolyte. UV–Visible, SEM, AFM and TEM analysis were used to characterize the synthesized particles and TiO2 nanotubes.

Abstract The present study reported a simple and novel method for the synthesis of highly stable cadmium sulfide nanoparticles (CdS NPs). The CdS NPs were characterized by transmission electron microscopy, X-ray diffraction, energy dispersive X-ray, particle size analyzer and Zeta potential measurement. The effective diameter of synthesized CdS NPs was found to be 18 nm and these were spherical in shape. The particles possessed better stability over 30 days of incubation period under static condition. The photocatalytic property of CdS NPs was also evaluated by the degradation of methylene blue dye under visible light source. The maximum photo-activity was observed at pH 8. The NPs exhibited excellent antimicrobial activity against Escherichia coli (ATCC 13534), E. coli (ATCC 25922), and Staphylococcus aureus (ATCC 25923). The present study may be considered for the large scale application in medical and environmental fields.

Abstract High performance polymer electrolyte for dye sensitized solar cell application has been prepared using suitable polymer matrix reinforced by reduced graphene oxide (RGO) nanosheets. RGO nanosheet has been synthesized using appropriately modified Hummer’s method. The matrix has been formulized as an optimized blend of polyethylene oxide and polyvinylidene fluoride – hexafluoro propylene (PEO/PVDF-HFP) to get expected high performance characteristics in terms of ionic conductivity, charge carrier concentration and diffusion coefficient. The same has been confirmed using electrochemical impedance spectroscopy and linear steady state voltammetry. Excellent stability of the electrolyte also has been recorded through efficiency retention study. Further, solar cell has been fabricated using the optimized formulation of PEO/PVDF-HFP/RGO nanosheet polymer electrolyte. The optimum performance in comparison with liquid electrolyte based solar cell has been authorized through photo voltaic performance study in terms of open circuit voltage (Voc), short circuit current (Jsc) and solar conversion efficiency.

Abstract Considering the minus points of Polysulfide redox electrolyte we explored Lanthanum Strontium Manganite to see the possibility of its usage in Quantum dot sensitized solar cells (QDSSCs) as electrolyte. Variations in material morphology synthesized via different methods and its effect on device performance and charge transfer dynamics across counter electrode are studied. The ceramic acts as a good passivation layer reducing the back transfer of electrons resulting in greater Voc and higher stability of cells. This study opens scope for use of such ceramics to completely replace the liquid electrolyte.

Abstract Ethylene-vinyl acetate (EVA), a copolymer of ethylene and vinyl acetate, is widely used as an encapsulant in the silicon solar module to bind the different layers together and protecting the solar cells from over stressing, cracking, and environmental effects. In this work, EVA has been recovered successfully from the used silicon solar module by thermal treatment at 170 °C temperature and the application of mechanical force. The established process is completely environment-friendly, as the EVA layer was recovered without any degradation and emission of any gas. The presence of extracted EVA and its chemical composition was confirmed from FTIR and EDAX measurements. It was observed from Thermogravimetry (TGA) and Differential thermogravimetry (DTG) that thermal degradation of EVA was a two-step process, and also the rate of reaction was fast in an air environment as compared to nitrogen environment. The extracted EVA is thermally stable until 215 °C in the air environment. From Differential scanning calorimetry (DSC) analysis, two endothermic peaks were observed at temperature 37 °C and 55 °C, which may be due to beginning of melting of vinyl acetate and ethylene crystallites respectively in air and nitrogen environment. From UV–visible spectroscopy, it was found that above 500 nm, the extracted EVA is transparent. After examined through the various characterization, it has been observed that extracted EVA shows quite similar properties as that of commercially available EVA. Therefore, the recovered EVA may be used in the encapsulation of solar modules and other applications in packaging and textile industries.

Abstract The study investigates the feasibility of integrating a quasi-solid polymer electrolyte with photoanodes made of titania nanocuboids and enhance the stability of dye-sensitized solar cells. Anatase titania nanocuboids are synthesized employing ammonium fluoride as structure directing agent by hydrothermal route, characterized, made into a homogeneous paste and utilized for fabricating photoanodes of various thicknesses. N719 sensitizer adsorbed on these photoanodes are paired with a new class of polyurethane based semi-IPN electrolyte system supporting I−/I−3 redox couple and sandwiched on top with a sputter coated platinum counter electrode. Integrated test cells are evaluated initially for the thickness dependent efficiency of the phtotoanodes to assess pore-filling ability of the macromolecular electrolyte used and limitations of fabrications. Optimization studies indicated 4 µm thick photoanodes to be ideal for obtaining the most favorable wetting characteristics and appropriate solid-electrolyte interface. The cells made with anatase nanocuboids shows an impressive 2.2% efficiency with a short circuit current density of 4.3 mA and an open circuit voltage of 0.76 V under AM 1.5 and simulated one Sun conditions. It is understood that due to reduced dye loading capacities of these thinner photoanodes, the photoconversion efficiencies and the overall cell efficiency apparently seems to be low, ca. 2–3%, alternate dye molecules with high molar extinction coefficients can effectively offset this loss. The efficiency is certainly seen to improve under 0.25 Sun owing to lower recombination possibilities. Most importantly, the stability tests carried out on these cells stored under ambient conditions demonstrate that these solid-state devices can retain ∼ 80% of their initial efficiency for at least 2600 h under the experimental conditions, which is devoid of hermetic sealing.

Abstract We have synthesized rare earth element cerium (Ce 3+ ) doped TiO 2 nanoparticles by using hydrothermal method. This doped TiO 2 is used as photoanode in dye sensitized solar cells (DSSCs). The nanoparticles were characterized by using X-ray diffraction (XRD), energy dispersive X-ray (EDX) and UV–visible spectroscopy. From XRD it was found that the anatase crystalline phase keeps unchanged after Ce 3+ doping while the crystallite size decreases. There is a decrease in the band gap of doped TiO 2 is observed, Ce 3+ positively changes the conduction band minimum of TiO 2 due to the introduction of unoccupied 4f states of Ce 3+ . The gel electrolyte was prepared by in situ polymerization of aniline in the mixture of PEO and c-MWCNT. The synthesized gel electrolyte was characterized by Fourier transform infrared spectroscopy (FTIR), SEM, and EDX analyses. The thermal stability of these gels also increased with the addition of c-MWCNT. The present study is concerned with effect of c-MWCNT and Ce 3+ on the conversion efficiency of the quasi solid state DSSCs. DSSCs fabricated with 0.1% c-MWCNT c in PEO/PAni and TiO 2 as photoanode achieved maximum conversion efficiency of 1.62%. The introduction of c-MWCNT improved ionic conductivity of composite electrolytes and enhanced interfacial contact between electrode and electrolyte. The Ce 3+ @TiO 2 photoanode influences the performance of DSSCs due to the increased electron injection. 0.5 wt% Ce 3+ @TiO 2 photoanode gives a maximum PCE of 4.08%, J sc of 7.36 mA cm −2 and V oc of 0.76 V.