• Bulletin of the Korean Chemical Society
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• 제34권6호
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• pp.1853-1856
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• 2013

$TiO_2$ hollow nanoparticles (HNPs) and their light scattering effect which influences on the photoelectric conversion efficiency of a dye-sensitized solar cell (DSSC) were investigated. When only HNPs were employed in DSSC as the anode layer material, the conversion efficiency (e.g., 0.96%) was the lowest, possibly due to scattering loss of incident light. However, DSSC fabricated by using HNPs as a scattering overlayer on the $TiO_2$ nanoparticles (P-25), showed higher conversion efficiency (4.02%) than that without using HNPs (3.36%).

• 한국재료학회지
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• 제30권2호
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• pp.81-86
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• 2020

MoO₃ metal oxide nanostructure was formed by hydrothermal synthesis, and a perovskite solar cell with an MoO₃ hole transfer layer was fabricated and evaluated. The characteristics of the MoO₃ thin film were analyzed according to the change of hydrothermal synthesis temperature in the range of 100 ℃ to 200 ℃ and mass ratio of AMT : nitric acid of 1 : 3 ~ 15 wt%. The influence on the photoelectric conversion efficiency of the solar cell was evaluated. Nanorod-shaped MoO₃ thin films were formed in the temperature range of 150 ℃ to 200 ℃, and the chemical bonding and crystal structure of the thin films were analyzed. As the amount of nitric acid added increased, the thickness of the thin film decreased. As the thickness of the hole transfer layer decreased, the photoelectric conversion efficiency of the perovskite solar cell improved. The maximum photoelectric conversion efficiency of the perovskite solar cell having an MoO₃ thin film was 4.69 % when the conditions of hydrothermal synthesis were 150 ℃ and mass ratio of AMT : nitric acid of 1 : 12 wt%.

• 한국전기전자재료학회논문지
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• 제29권12호
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• pp.819-823
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• 2016

DSSC (dye-sensitized solar cell) is expected to be one of the next-generation photovoltaics because of its environment-friendly and low-cost properties. However, commercialization of DSSC is difficult because of the electrolyte leakage. We propose thermal curable base on silicon resin and apply a unit cell and large area ($200{\times}200mm$) dye-sensitized solar cell. The resin aimed at sealing of DSSC and gives a promising resolution for sealing of practical DSSC. In result, the photoelectric conversion efficiency of the unit cell and the module was 6.63% and 5.49%, respectively. In the durability test result, the photoelectric conversion efficiency of the module during 500, 1,000, 1,500 and 2,000 hours was 0.73%, 0.73%, 1.82% and 2.36% respectively. It was confirmed that the photoelectric conversion efficiency characteristics are constant. We have developed encapsulation material of thermal curing method excellent in chemical resistance. A sealing material was applied to the dye-sensitized solar cell and it solved the problem of durability the dye-sensitized solar cell. Sealing material may be applied to verify the possibility of practical application of the dye-sensitized solar cell.

• Bulletin of the Korean Chemical Society
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• 제33권4호
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• pp.1220-1224
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• 2012

This study examines the photoelectric conversion efficiency of dye-sensitized solar cells (DSSCs) when nanometer-sized Y (0, 0.1, 0.5, and 1.0 mol %)-incorporated $TiO_2$ prepared using a solvothermal method is utilized as the working electrode material. The photoelectric properties of the Y-$TiO_2$ used in DSSCs were studied by frequency-resolved modulated photocurrent/photovoltage spectroscopy. The recombination was much slower in the Y-$TiO_2$-based DSSCs than in the pure $TiO_2$-assembled DSSC. Compared to that using pure $TiO_2$, the energy conversion efficiency was enhanced considerably by the application of Y-$TiO_2$ in the DSSCs to approximately 6.08% for 0.5 mol % Y-$TiO_2$.

• 한국재료학회지
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• 제32권2호
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• pp.94-97
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• 2022

We fabricated 3 types of ETL, mp TiO₂, ZnO, and ZnO coated on mp TiO₂(ZMT) to compare the photoelectric conversion efficiency (PCE) and fill factor (FF) of Perovskite solar cells. The structure of the cells was FTO/ETL/Perovskite (CH₃NH₃PbI₃)/spiro-MeOTAD/Ag. SEM morphology assessment of the ETLs showed that mp TiO₂ was porous, ZnO was flat, and the ZMT porous surface was filled with a thin layer. Via XRD measurements, the crystal structures of mp TiO₂ and ZnO ETL were found to be anatase and wurtzite, respectively. The XPS patterns showing energy bonding of mp TiO₂, ZnO, and ZMT O 1s confirmed these materials to be metal oxides such as ETL. The electrical characteristics of the Perovskite solar cells were measured using a solar simulator. Perovskite solar cells with ZMT ETL showed showed PCE of 10.29 % than that of conventional mp TiO₂ ETL devices. This was considered a result of preventing Perovskite from seeping into the ETL and preventing recombination of electrons and holes.

• Bulletin of the Korean Chemical Society
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• 제32권9호
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• pp.3317-3322
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• 2011

This study examines the photoelectric conversion efficiency of dye-sensitized solar cells (DSSCs) when nanometer-sized Zr (0.1, 0.5, and 1.0 mol %)-$TiO_2$ prepared using a solvothermal method is utilized as the working electrode material. The particle sizes observe in the transmission electron microscopy (TEM) images are < 30 nm in all samples. The absorption band is slightly broadened at the tail for the 0.1 mol % Zr-$TiO_2$, and the intensity of the photoluminescence (PL) curves of the Zr-incorporated $TiO_2$ is significantly smaller than that of the pure $TiO_2$. Compared to that using pure $TiO_2$, the energy conversion efficiency is enhanced considerably by the application of Zr-$TiO_2$ in the DSSCs to approximately 6.17% for 0.5 mol % Zr-$TiO_2$ with the N719 dye (10.0 ${\mu}m$ film thickness and 5.0 mm ${\times}$ 5.0 mm cell area) under 100 mW/$cm^2$ of simulated sunlight.

• Advances in nano research
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• 제13권5호
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• pp.475-485
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• 2022

Crystalline silicon photovoltaic cells have advantages of zero pollution, large scale and high reliability. A major challenge is that sunlight wavelength with photon energy lower than semiconductor band gap is converted into heat and increase its temperature and reduce its conversion efficiency. Traditional cooling PV method is using water flowing below the modules to cool down PV temperature. In this paper, the idea is proposed to reduce the temperature of the module and improve the energy conversion efficiency of the module through the modulation of the solar spectrum. A spectrally selective nanofilm reflector located directly on the surface of PV is designed, which can reflect sunlight wavelength with low photon energy, and even enhance absorption of sunlight wavelength with high photon energy. The results indicate that nanofilm reflector can reduce spectral reflectivity integral from 9.0% to 6.93% in 400~1100 nm wavelength range, and improve spectral reflectivity integral from 23.1% to 78.34% in long wavelength range. The nanofilm reflector can reduce temperature of PV by 4.51℃ and relatively improved energy conversion efficiency of PV by 1.25% when solar irradiance is 1000 W/m². Furthermore, the nanofilm reflector is insensitive in sunlight's angle and polarization state, and be suitable for high irradiance environment.

• 한국전기전자재료학회논문지
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• 제25권11호
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• pp.902-905
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• 2012

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 $N_2$, and $O_2$. 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 $O_2$ 50 sccm and 50 W and that result were 7.643 ${\Omega}/cm^2$ and 17.113 nm, respectively. The best efficiency result was obtained by $O_2$ 50 sccm and 50 W and that result of Voc, Jsc, FF and efficiency were 7.03 V, 14.88 $mA/cm^2$, 63.75% and 6.67%, respectively.

• 반도체디스플레이기술학회지
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• 제13권2호
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• pp.37-44
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• 2014

In this study, the performance of dye-sensitized solar cells with different thickness of the photelectrode film was simulated by using the electron-diffusion differential model. Through this simulation, the relationships between the thickness of the photoelectrode film and the performances (open-circuit voltage, short-circuit current density, and overall photoelectric-conversion efficiency) of cells were understood and the performances with different thickness of the photoelectrede film were also examined. For considering the refractive index in the liquid electrolyte and exploring the scattering effect of titanium dioxide particles with different sizes using the Mie light-scattering theory, the highest scattering effect of each particles was found out and the optimal size of the titanium dioxide particle was determined for light scattering in the photoelectrode film of dye-sensitized solar cell. Through experiment, the mixed titanium dioxide cell was better than the single titanium dioxide cell and generated a higher overall conversion efficiency because the optimal titanium dioxide particles in the phoelectrode film as light scattering.

• 마이크로전자및패키징학회지
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• 제29권1호
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• pp.71-75
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• 2022

Graphene oxide를 ZnCl₂:NaCl 전해질과 함께 교반한 후 순환 전압전류법에 의해 전기화학적으로 제막하여 유기태양전지용 전자수송층 제막과정을 단순화하고 이를 갖는 유기태양전지를 제작하였다. 소자의 구조는 FTO/ZnO:graphene 전자수송층/P3HT:PCBM 광활성층/PEDOT:PSS 정공수송층/Ag이다. ETL의 형태 및 화학적 특성은 주사전자현미경(scanning electron microscopy, SEM), X선 광전자 분광법(X-ray photoelectron spectroscopy, XPS), 라만 분광법으로 확인하였다. XPS 측정결과 ZnO 금속산화물 및 탄소결합이 동시에 확인되었고, 라만 분광법에서 ZnO와 graphene 피크를 확인하였다. 제작한 태양전지의 전기적 특성을 솔라시뮬레이터로 측정하였고 0.05 V/s의 속도로 2회 제막한 ETL 소자에서 1.94%의 가장 높은 광전변환효율을 나타내었다.