The possibility of a dye-sensitized solar cell (DSSC) submodule was evaluated as an independent power source that can drive a smart liquid crystal window (SLW) that selectively blocks sunlight when electricity is applied. In order to save energy and increase the functionality of buildings, SLW operation was supplied directly from DSSC submodule, rather than connecting to the existing power system and external power sources. It was confirmed that the SLW can control light transmittance through self-generation using the DSSC submodule composed of 6 cells at low light of 2,500 lux. These results imply that there is a high possibility of combining smart windows and DSSCs suitable for window-type building-integrated photovoltaic (BIPV) systems. DSSCs, which can self-generate power in low light, are expected to increase their usability in urban BIPV systems through combination with smart window technology.
Currently, the most developed new energy source is solar energy. Because solar power is installed outside, it is exposed to many pollutants. Pollutants are causing the characteristics of solar energy to deteriorate. Therefore, this study aims to develop a water-repellent coating to prevent contamination of solar modules. Silica and Titania materials are mainly used as water-repellent coating materials. In this study, it was based on silica and the contact angle characteristics were measured according to the change in the amount of silica and ammonia water added and the number of coatings. As a result of the measurement, it was confirmed that the contact angle was more than 60 degrees when 0.5 mol of TEOS was added to 50 mL and 0.15 M when 1 mL of ammonia water was added to 296.47 ml of distilled water. And it was confirmed that the contact angle improved when the number of coatings was applied twice. A water-repellent coating material was applied to low iron tempered glass used to protect dye-sensitized solar cell modules. The characteristics of the module were measured after spraying DI-Water on low-emission tempered glass with a water-repellent coating. As a result of the measurement, the efficiency of the module without application, the efficiency of the module coated once, and the module coated twice were 4.87%, 4.90%, and 4.91%, respectively. It was confirmed that the efficiency of the module increased by applying water-repellent coating. As a result of this study, it is determined that the water-repellent coating material will help improve solar power generation efficiency and lifespan by being self-cleaning and non-reflective.
This study examines a manufacturing process for the photoelectrode material of dye-sensitized solar cell (DSSC) intending to increase efficiency through the surface plasmon resonance phenomenon of nanoparticles with a composite structure made of Ag and TiO2. This invention involves the use of Ag and TiO2 nanoparticles in the solar cell. These nanoparticles cause surface plasmon resonance, which amplifies and scatters incident solar energy, enhancing the dye’s rate of light absorption. It also makes it possible to absorb energy in wavelength ranges that were previously difficult to do, which increases efficiency. Centrifugal separation and heat synthesis are used to create the composite metal structures, and certain combinations are used to decide the particle morphologies. To increase the efficiency of organic solar cells and DSSC, the Ag/TiO2 composite structure is therefore quite likely to be used.
Raman spectra of a-C:H thin films deposited with an unbalanced magnetron sputtering system showed that the G peak shifted to a higher wavenumber as the target power density increased and ID/IG ratio increased from 0.902 to 1.012. Moreover, the transmittance of a-C:H films fabricated at 60 nm tended to decrease with increasing target power density; at 550 nm in the visible light region, the transmittance decreased from 69% to 58%. The rms surface roughness values of the a-C:H thin films decreased with increasing target power density, and varied from 1.11 nm to 0.71 nm. In order to achieve efficient light trapping, the light scattering at the rough interface must be enhanced. Consequently, the surface roughness of the thin film will decrease with the target power density. Further, the refractive index and reflectivity of the a-C:H thin films increased with increasing target power density; however, the Brewster angle decreased with the target power density. Hence, dye-sensitized solar cells using an a-C:H antireflective coating increased the CE, VOC, and JSC by approximately 8.6%, 5.5%, and 4.5%, respectively.
Recently, the application field of solar panels is increasing. Accordingly, the demand for flexible devices is also steadily increasing. It is therefore necessary to develop TiO2 paste for low-temperature annealing for flexible DSSC fabrication. In this study, the TiO2 paste for low-temperature annealing with varying molar ratio of titanium isopropoxide (TTIP) was prepared, and DSSC was fabricated and its characteristics were compared. As a result, there was no deformation of the particles on the surface in the SEM data. However, the highest open circuit voltage, short circuit current, and fill factor were measured in the DSSC unit cell prepared by adding 0.5 mol of TTIP to the TiO2 paste, and the highest efficiency was 4.148%.
A novel heteroleptic ruthenium(II) complex bearing a 4-picolinic acid unit as anchoring ligands (trans-dithiocyanato bis(4-picolinic acid)ruthenium(II) (trans-H1)) was synthesized and its chemical structure was identified by 1H-NMR, FT-IR and mass spectroscopy. The optical, thermal, electrochemical and dye adsorption properties of trans-H1 dye were investigated and compared with those of the gold standard ruthenium complex, Ru(4,4``-dicarboxy-2,2``-bipyridine)2cis(NCS)2 (N3). DSSCs based on trans-H1 dyes were examined under the illumination of AM 1.5 G, 100 mWcm-2 and exhibited typical photovoltaic properties with an open-circuit voltage (VOC) of 0.46 V, a short-circuit current (JSC) of 4.10 mA·cm-2, a fill factor (FF) of 60.4%, and a conversion efficiency (PCE) of 1.14%.
Among several types of energy saving smart window technologies, the leader, the dynamic EC (electrochromic) window one needs integrated PV (photovoltaics), to minimize expensive electrical wiring as well as to obviate the need for external energy. Self-powered smart windows were reviewed according to PV types used. DSSCs (dye sensitized solar cells) were found to be compatible with EC cells, to have several categories of next generation smart windows such as PECCs (photoelectrochromic cells), PVCCs (photovoltachromic cells), EC polymer PECCs. In addition silicon solar cells and third generation solar cells were investigated. They are summarized in a table showing their advantages and disadvantages respectively for a fast comparison. The strategy to expedite the commercialization of these next generation smart windows includes developing retrofit smart window coverings for use on flexible polymer substrates adhered to the inside surface of a window and easily replaced after use for upto 10 years.
Rhodamine B (RhB) was utilized as a dye sensitizer for dye-sensitized solar cells (DSSCs) and its photovoltaic property was examined under the illumination of AM 1.5 G, 100 mWcm-2. DSSCs based on RhBexhibited typical photovoltaic properties with an open-circuit voltage (VOC) of 0.34 V, a short-circuit current (JSC) of 1.55 mA·cm-2, a fill factor (FF) of 50%, and a conversion efficiency (PCE) of 0.26%. In order to further improve the photovoltaic properties of RhB-based DSSCs, the effect of (i) incorporating a strong electron-donating NCS unit into the RhB molecular backbone, (ii) combining a bis-negatively charged zinc complex anion (Zn-dmit2, dmit=di-mercapto-dithiol-thione) with the amine cation of RhB, (iii) co-adsorbing RhB dyes with chenodeoxycholic acid (CDCA) molecules onto porous TiO2 electrodes, was investigated and discussed.
This paper is designed to find out where power reaches the highest point as the load of solar cells varies. In addition, the current and power were measured when irradiation changes, and the correlation between current and power was investigated. On top of that, experiments were conducted with the light volume kept constant and with the incoming light angle changing in order to figure out the incoming light angle that produces the most power and to conduct analyses. It was ascertained that if the load increases, the current decreases and the voltage increases. Since the power of 0.9828[W] was the highest when measurements were done, it can be said that when a load of 30[%] is applied to the solar cells, they are the most efficient.
Photo electrode is an important component of DSSC, so this paper did some research on it. Through the method of adding PEG additive into TiO2 paste, the electrical characteristics and efficienciesof DSSCs with photo electrode surface area were studied. In the case of not adding PEG in TiO2 paste,26 ㎛ thickness TiO2 photo electrode shows 5.081% efficiency. The highest short circuit current densitywas 10.476 mA/cm2. The structure of porous TiO2 film can be controlled through changing the PEGadditive amount in TiO2 paste and the molecular weight of PEG. When the additive amount of PEG20,000 in TiO2 paste reaches 5%, the peak efficiency with 26 ㎛ thickness TiO2 photo electrode was5.387% and its highest current density were 11.084 mA/cm2.
Photo electrode is an important component for DSSC. DSSCs electrical characteristics and efficiencies fabricated with different TiO2 photo electrodes thickness and modified phoro electrode surface area were studied. 11 ㎛ TiO2 photo electrode shows a 4.956% efficiency. The highest short circuit current density was a 9.949 mA/cm2. Efficiencies and short circuit current density increased as tape casting thickness decreased. Modified surface area of the photo electrode by needle stamp processing were studied. 200 times needle stamp processing on photo electrodes shows a highest 5.168% efficiency. Also the short circuit current density was a 10.261 mA/cm2.
In this study, the W-interconnected dye-sensitized solar cell (DSSC) modules composed of a number of rectangular cells connected in series were investigated, where neighboring cells are processed in reverse. The DSSC modules, a module of dimension about 200 mm × 200 mm, were fabricated with different working electrode width ranging from 5 mm to 21 mm. The short-circuit current of the module increased as the working electrode width increased. Whereas, the decrease in the working electrode width resulted in the increase of the conversion energy efficiency, fill factor, and open-circuit voltage, which is explained by the fact that the possibility that electrons are recombined along their path on the transparent conductive oxide substrate decreases. The module with the conversion energy efficiency of 3.59% was obtained with the working electrode width of 5 mm.
DSSCs electrical characteristics and efficiency fabricated with different tape casting thickness Pt counter electrodes and different thickness between TiO2 photo electrode and Pt counter electrode substrate were studied. 1 layer Pt counter electrode shows 3.979% efficiency. Efficiency increased as tape casting thickness decreased. The lowest open-circuit voltage was a 0.726 V and the highest short-circuit current was a 2.188mA on 1 layer Pt counter electrode. On the different thickness between two substrates, the lowest open-circuit voltage 0.712 V and the highest short-circuit current 2.787mA was measured at 60 ㎛ surlyn film thickness and it shows the highest value of 5.067% efficiency.
This study is explore the photoelectric conversion change of dye-sensitized solar cells with surface treatment of the conductive substrate. gases of FTO surface treatment were N2, and O2. Treatment conditions of surface were gas flux from 25 sccm to 50 sccm and RF power were from 25 W to 50 W. Treatment time and pressure were fixed 5 min and 100 mtoor. The best sheet resistance and surface roughness were obtained by O2 50 sccm and 50 W and that result were 7.643 Ω/㎠ and 17.113 nm, respectively. The best efficiency result was obtained by O2 50 sccm and 50 W and that result of Voc, Jsc, FF and efficiency were 7.03 V, 14.88 mA/㎠, 63.75% and 6.67%, respectively.
The sol-gel method has been widely used to synthesize the TiO2 for dye sensitized solar cells and has advantages of easily fabrication process, controlling the TiO2 phase and getting transparent thin-film composed of the TiO2. In this paper, we synthesized the crystalline TiO2 by sol-gel method controlled by the quantity ratio of Nitric acid and Ammonium hydroxide additives. The best efficiency result was obtained by 0.05 M Ammonium hydroxide and that results of Voc, Jsc, FF, and efficiency were 0.68 V, 3.28 mA/cm2, 58.14 and 5.21%, respectively.
DSSCs efficiency by thickness of TiO2 photoelectrode and thickness differences between two substrates studied. DSSCs is made of the doctor blade method and photoelectrode annealing temperature elevated in a different ways. In addition, cells efficiencies of according to the different thickness between TiO2 photoelectrode substrate and Pt counter electrode was measured. Efficiency of DSSCs made with TiO2 photoelectrode of 18 ㎛thickness and the gap difference between the substrate 28 ㎛shows a highest 4.805% efficiency.
As an alternative energy, Dye-sensitized solar cells (DSSCs) have received much attention due to low cost manufacturing procedure and high energy consumption rate. Incorporating scattering centers in the nanocrystalline photoanode or additional scattering layers on the nanocrystalline photoanode is an effective way to enhance the light harvest efficiency of the photoanode and the performance of dye-sensitized solar cells (DSSCs). The light scattering abilities of these scattering layers also depend on the relative sizes and phase of the particles in the layers. A higher surface area is normally obtained using large particle sizes. Therefore, transparent high surface area TiO2 layers and an additional scattering layer consisting of TiO2 -Rutile 500 ㎚paste with relatively larger particles are attractive. In this work, we investigates the applicability of a hybrid TiO2 electrode (or a working electrode with a light scattering layer) in a DSSCs. We fabrication various thin film using TiO2 paste 20 ㎚and TiO2 paste 500 ㎚. As a result, the efficiency of the a single structure thin film was 3.35% and the efficiency as scattering layer of hybrid structure thin film was 4.36%, 4.73%.
In general, a photoelectrode in DSSC(dye sensitized solar cell) are fabricated by using the TiO2 (Titanium dioxide) to realize high efficiency and the efficiency of DSSC is affected by the size, the shape and the property of TiO2. We synthesized the crystalline TiO2 by sol-gel method. In spite of many merits, only weakness for the sol-gel method is taking many process times. To solve this problem, we reduced the fabricating processes. The reduced process is the making process that is TiO2 sol to TiO2 powder with including of two heat treatment and two mixing. We could simplify the process by preparing TiO2 sol to TiO2 paste directly. As a result, DSSC fabrication process is simplified and we have obtained the efficiency best result 3.88% with VOC=0.71 V, JSC=8.70 mA/cm-2, and FF=62.37%, respectively.
The adsorption kinetic study of ruthenium complex, N3, onto nanoporous titanium dioxide (TiO2) photoanodes has been carried out by measuring dye uptake in-situ. Three simplified kinetic models including a pseudo first-order equation, pseudo second-order equation and intraparticle diffusion equation were chosen to follow the adsorption process. Kinetic parameters, rate constant, equilibrium adsorption capacities and related coefficient coefficients for each kinetic model were calculated and discussed. It was shown that the adsorption kinetics of N3 dye molecules onto porous TiO2 obeys pseudo second-order kinetics with chemisorption being the rate determining step. Additionally the heterogeneous surface and the pore size distribution of porous TiO2 adsorbents were also discussed.