• 한국전기전자재료학회논문지
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• 제25권1호
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• pp.37-43
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• 2012

We were studied that AZO conductive thin film can substitute for FTO electrode in dye sensitized solar cell. Three types of AZO films were deposited on soda-lime glass(AZO/glass, AZO/AZO/glass, textured AZO/AZO/glass) using RF magnetron sputtering process and investigated their properties of electrical, optical, and photoelectric conversion rate. The textured AZO/AZO/glass has the lowest resistivity of $3.079{\times}10^{-4}\;{\Omega}cm$ among other films. And the optical transmittance rate was better than both non textured AZO/AZO/glass and FTO/glass in the visible region. After manufacturing dye solar cells using the three types of AZO films, the textured AZO/AZO/glass showed the highest photoelectric conversion rate of 3.68% among AZO samples. But the transformation rate was slightly lower than FTO cells (4.52%). However, the conductive film of textured AZO/AZO/glass can be applicable to use an electrode in solar cells as cost-effective products.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 추계학술대회 논문집
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• pp.128-130
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• 2008

One of methods to increase the efficiency of a dye-sensitized solar cell(DSC) is the effective usage of the incident light. It can be controlled by using a light scattering layer. The light scattering effect makes that the optical path length of incident light to DSC increases. And then, the photocurrent and the efficiency is increased because of the increase of dye adsorption and the abundant amount of the light. In this study, we apply the light scattering layer to DSC by using two $TiO_2$ pastes that have different particle sizes. As a result, the photocurrent increases and the total efficiency is also increases in the case of using large-sized $TiO_2$ particle as the light scattering layer.

• 전기학회논문지
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• 제60권1호
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• pp.114-118
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• 2011

Dye-Sensitized Solar Cells(DSSCs) consist of a titanium dioxide($TiO_2$) nano film of the photo electrode, dye molecules on the surface of the $TiO_2$ film, an electrolyte layer and a counter electrode. But two transparent conductive oxide(TCO) substrates are estimated to be about 60[%] of the total cost of the DSSCs. Currently novel TCO-less structures have been investigated in order to reduce the cost. In this study, we suggested a TCO-less DSSCs which has titanium double layer electrodes. Titanium double layer electrodes are formed by electron-beam evaporation method. Analytical instruments such as electrochemical impedance spectroscopy, scanning electron microscope were used to evaluate the TCO-less DSSCs. As a result, the proposed structure decreases energy conversion efficiency and short-circuit current density compared with the conventional DSSCs structure with FTO glass, while internal series impedance of TCO-less DSSCs using titanium double layer electrodes decreases by 27[%]. Consequently, the fill factor is improved by 28[%] more than that of the conventional structure.

• Bulletin of the Korean Chemical Society
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• 제35권4호
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• pp.1165-1168
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• 2014

We prepared dye-sensitized solar cells (DSSCs) with enhanced energy conversion efficiency using open-ended $TiO_2$ nanotube arrays with a $TiO_2$ scattering layer. As compared to closed-ended $TiO_2$ nanotube arrays, the energy conversion efficiency of the open-ended $TiO_2$ nanotube arrays was increased from 5.63% to 5.92%, which is an enhancement of 5.15%. With the $TiO_2$ scattering layer, the energy conversion efficiency was increased from 5.92% to 6.53%, which is an enhancement of 10.30%. After treating the open-ended $TiO_2$ nanotube arrays with $TiCl_4$, the energy conversion efficiency was increased from 6.53% to 6.89%, a 5.51% enhancement, which is attributed to improved light harvesting and increased dye adsorption.

• Bulletin of the Korean Chemical Society
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• 제33권4호
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• pp.1204-1208
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• 2012

A new photoelectrode composed of $Sb_6O_{13}$ nanoparticles with the size of 20-30 nm has been prepared via thermolysis of a colloidal antimony pentoxide tetrahydrate ($Sb_2O_5{\cdot}4H_2O$) suspension. The $Sb_6O_{13}$ electrode showed good semiconducting properties applicable to dye-sensitized solar cells (DSSCs); the energy band gap was estimated to be $3.05{\pm}0.5$ eV and the position of conduction band edge was close to those of $TiO_2$ and ZnO. The DSSC assembled with the $Sb_6O_{13}$ photoelectrode and a conventional ruthenium-dye (N719) exhibited the overall photo-current conversion efficiency of 0.74% ($V_{oc}$ = 0.76 V, $J_{sc}=1.99\;mAcm{-2}$, fill factor = 0.49) under AM 1.5, $100\;mWcm^{-2}$ illumination.

• Bulletin of the Korean Chemical Society
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• 제30권1호
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• pp.172-176
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• 2009

The nature and morphology of titanium dioxide films play a significant role in determining the overall efficiency of dye-sensitized solar cell (DSSCs). In this work, the preparation of nanostructured titania particles by sol-gel method (SG-$TiO_2$) and its characterization were investigated for the application of DSSCs. The samples were characterized by XRD, XPS, FE-SEM, BET and FT-IR analysis. The energy conversion efficiency of SG-$TiO_2$ was approximately 8.3 % under illumination with AM 1.5 (100 mW/$cm^2$) simulated sunlight. DSSCs made of SG-$TiO_2$ nanocrystalline films as photoanodes achieved better energy conversion efficiency compared to those prepared using commercially available Degussa P25.

• Journal of Electrical Engineering and Technology
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• 제6권5호
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• pp.684-687
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• 2011

In this study, we investigate the photovoltaic performance of transparent conductive indium tin oxide (ITO), titanium-doped indium oxide (ITiO), and fluorine-doped tin oxide (FTO) films. ITO and ITiO films are prepared by radio frequency magnetron sputtering on soda-lime glass substrate at $300^{\circ}C$, and the FTO film used is a commercial product. We measure the X-ray diffraction patterns, AFM micrographs, transmittance, sheet resistances after heat treatment, and transparent conductive characteristics of each film. The value of electrical resistivity and optical transmittance of the ITiO films was $4.15{\times}10^{-4}\;{\Omega}-cm$. The near-infrared ray transmittance of ITiO is the highest for wavelengths over 1,000 nm, which can increase dye sensitization compared to ITO and FTO. The photoconversion efficiency (${\eta}$) of the dye-sensitized solar cell (DSC) sample using ITiO was 5.64%, whereas it was 2.73% and 6.47% for DSC samples with ITO and FTO, respectively, both at 100 mW/$cm^2$ light intensity.

• 한국전기전자재료학회논문지
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• 제26권3호
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• pp.240-245
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• 2013

The utilization of a fluoran leuco sensitizer, 2-anilino-6-dibutyl amino-3-methylfluoran (ODB-2), for dye-sensitized solar cells (DSSCs) was investigated through the examination of the adsorption of ODB-2 molecules onto the surfaces of porous titanium dioxide (titania, $TiO_2$) films and the photovoltaic properties of ODB-2-based DSSCs. Despite of the absence of the specific anchoring groups with titania, ODB-2 dye molecules were spontaneously adsorbed onto the titania surfaces because the lactone ring in ODB-2 was opened and changed into the carboxylic acid (-COOH) by releasing protons from the surfaces ($TiOH_2{^+}$) of titania, which consequently leads to the chemisorption reaction of ODB-2 molecules to the active sites of titania. DSSCs based on ODB-2 exhibited typical photovoltaic properties with an open-circuit voltage ($V_{OC}$) of 0.19 V, a short-circuit current ($J_{SC}$) of $0.30\;mA{\cdot}cm^{-2}$, a fill factor (FF) of 37%, and a conversion efficiency (PCE) of 0.02%.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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• pp.422-424
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• 2008

A serious problem of the 21st century is the supply of energy resources. Reserves of fossil fuels are facing depletion: renewable energy resources must be developed in this era. Dye sensitizedsolar cells(DSC) have been very economical and easy method to convert solar energy to electricity. DSC can reach low costs in future outdoor power applications. However, to commercialize the DSC, there are still many shortages to overcome. When the DSC is commercialized in the near future, the productivity is an important factor. In the process of soaking in a dye, it usually takes $12\sim24$ hours. In this study, we varied the dye coloring temperature from $0^{\circ}C$ to $60^{\circ}C$. At the temperature of $40^{\circ}C$, DSC cell showed the best performance. We also expect the reduction of the time soaking in a dye. Counter electrode surface of DSC is deposited by RF magnetron sputtering under the conditions of Ar $2.8{\times}10^{-3}$ torr, RF power of 120W and substrate temperature of $100^{\circ}C$.

• 전기학회논문지
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• 제58권12호
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• pp.2425-2430
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• 2009

Dye-sensitized solar cell(DSC) is composed of a dye-adsorbed nanoporous $TiO_2$ layer on fluorine-doped tin oxide(FTO) glass substrate, electrolyte, and platinium doped counter electrode. Among these, a dye-absorbed nanoporous $TiO_2$ layer plays an important role in the performance of the DSC because the injected electrons from excited dye molecules move through this layer. And the condition of $TiO_2$ layer such as the morphology and thickness affects on the electron movement. Therefore, the performances and the efficiency of DSC change as the thickness of $TiO_2$ layer is different. Electrochemical Impedance Spectroscopy(EIS) is the powerful analysis method to study the kinetics of electrochemical and photoelectrochemical processes occurring in the DSC especially the injected electron movements. So we analyzed the DSCs with different $TiO_2$ thicknesses by using EIS to understand the influence of the $TiO_2$ thickness to the performance of the DSC clearly. Finally, we got the EIS analysis on the DSC with different $TiO_2$ thickness from the internal resistance of the DSC, the electron life time and the amount of dye molecules.