The amount of electric power for photovoltaic power generation depends on the location of the power plant and the direction of solar cell. The solar cell controls the generation of solar power plants. Therefore, the structure of solar cell, manufacturing method, and optic technology were factors contributing to increased solar cell efficiency; however, the technical limit has been reached. Herein, we propose a new method to increase the solar cell efficiency using a wavelength conversion technology that converts ultraviolet and infrared rays, which are not effectively used in solar cells, into effective wavelength of solar cell. We used fluoride Na(Ca)YF4 phosphor for wavelength conversion. Then, a wavelength-conversion fluorescent paste, prepared using an organic-silicon binder, was used to prepare a film that was applied to Si solar cells. It was confirmed that conversion efficiency improved by 5% or more.
We fabricated 1-D and 2-D diffraction gratings of SiOx anti-reflection (AR) film grown on a quartz substrate and integrated them into a c-Si photovoltaic (PV) submodule. The light-trapping effect of the resulting submodules was studied in terms of the oblique optical incident angle, θi. As the θi increased, solar conversion efficiency, η, was improved as expected by the increased optical transmission caused by the grating. For θi≤30°, the relative solar conversion efficiency, Δη, of a 1-D SiOx (t=300 nm) grating, compared to that of a flat SiOx AR-coated integrated PV submodule, was improved very little, with a small variation of within 2%, but increased markedly for θi≥40°. We observed a change of Δη as large as 10.7% and 9.5% for the SiOx grating of period t=800 nm and 1200 nm, respectively. For a 2-D SiOx (t=300 nm) grating integrated PV submodule, however, the optical trapping behavior was similar in terms of θi but its variation was small, within ±1.0%.
P3HT:PCBM bulk heterojunction solar cells added with ferroelectric polymer were fabricated and characterized. By incorporating P3HT:PCBM solar cell with P(VDF-TrFE) ferroelectric additive, the power conversion efficiency was increased up to nearly 50%. Photoacoustic analysis on this phenomena was carried out for the first time. Through this study, we find that the ferroelectricity of the polymer additive plays the key role in the enhancement of the power conversion efficiency of the organic solar cell by suppressing the non-radiative recombination of charge transfer exciton more effectively.
In this work, according to temperature and time of hydrothermal synthesis, the electrochemical properties of TiIO2 particle using TTIP based on thanging temperature and time in the hydrothermal synthesis were analyzed and optimized temperature and time were derived. When hydrothermal synthesis were analyzed and optimized temperature and time were derived. When hydrothermal synthesis temperature and time were 200℃ and 1 h, respectively. The fabricated DSSC delivered the best electrochemical properties. In that case, TiO2 particle size was 13.018 nm, electron transport time was 2.34×103s and recombination time was 4.01×102s. The lowest impedance of 13.52 Ω and Voc, Jsc, FF is 0.70 V, 11.50 mAcm2, 65.62%, respectively and corresponding efficiency of 5.34% was considered as the optimal.
In this paper, the low-temperature sintering of TiO2 is approached to solve the problem of high temperature sintering which decreases the interconnection between particles or between substrate and particle. TiO2 paste is prepared with Titanium (Ⅳ) isopropoxide as the precursor material and calcinate at different conditions (low temperature). In the results, since the changing of temperature and time of sintering, crystalline phase do not change and the intensities of anatase, rutile phase are higher. At 110℃, 7 h sintering condition, crystalline size of anatase and rutile phase are the smallest which are 13.07 and 17.47 nm, respectively. In addition, the highest zeta potential is about 32.77 mV and the repulsive force increases thus leading to the best of the dispersion characteristics between TiO2 particles. Futhermore, DSSCs at that condition exhibits the highest efficiency with the values of Voc, Jsc, FF and η are 0.69 V, 8.60 mA cm-2, 67.93% and 4.06%, respectively.
In this Paper, we have developed1 a low temperature process to make two type of Paste by using TIO2 nanoprticles(P25). The interconnections between substrate and TiO2 films or link between particles of free-binder Paste (FP1, FPZ, FP3) is very poor. Therefore, the Titanium(IV) isopropoxide was added to the TP paste to improve the interconnection. Electron transport time (Tt) and recombination time (Tr) are analyzed by IMPS (intensity-modulated photocurrent spectroscopy) and INIVS (Intensity-modulated photovltage spectroscopy). In the results, Tt of TP paste based DSSCs (about 4.3×10-3) is faster than other samples. Tt is Ionger from 2.7×10-2 s of FP2 to 3.0×10-2 s of TP. A solar conversion efficiency (DSSCs) of TP 15 3.54% for an incident solar energy of 100 mw cm-2(meanwhile, 2. 70% for DSSCs With FP2). The c아1versioIl efficiency is increased by 1.3 times.
Hybrid SiO2-TiO2 photoelectrode with different type of layers was investigated in dye-sensitized solar cells (DSSC). Use of a thin layer of nanocrystalline TiO2 would imply reduction in the amount of dye coverage, however, lower amount of dye in the thin films would imply fewer electron generation upon illumination. So, thus, it becomes necessary to include a SiO2-TiO2 layer for increase light harvesting effect such that the lower photon conversion due to thin layer could be compensated. In this paper reports the use of transparent high surface area TiO2 layer and an additional SiO2-TiO2 layer, thus ensuring adequate light harvesting in these devices. The best solar conversion efficiency 6.6% under AM 1.5 was attained with a multi-layer structure using TiO2 layer/SiO2-TiO2 layer/TiO2 layer for the light harvesting and this had resulted to about 44% increase in photocurrent density of dye-sensitized solar cells.