This project plans to understand the relation between Electroluminescence (EL) images and the defect structure of solar cells. Up to now, the PV industry hasn’t found any rapid and effective ways to identify the microcracks on multi-crystalline silicon (mc-Si) solar cells, just as they did to single-crystal silicon solar cells. By observing the change of EL images of the mc-Si solar cells during an aging test, we hope to clarify how the aging process and the defects of solar cells/modules influence the EL images and the electric power output. We applied different image processing methods of EL images to identify the location of the defects structures. Our goal is to develop an automatic identification program. The experimental results show that the variations of the grayscale levels of the EL images were small and located within the predicted range. That means the cells’ efficiency was not affected by the aging test. We colorized certain grayscale level values in red and into four colors or 16 colors. Both methods allowed the rough distinguishing of high and low efficient areas. However, specific defects such as cracks could not be identified by these methods. A semi-automatic colorization method was successfully used to increase the interpretation accuracy of the EL images although there were still some drawbacks. In the near future, we intend to apply blocks algorithm to automatic colorization of the EL images.

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We practically measured the charging efficiency of greater than 85% by using a 100×30 cm2 plastic CIGS solar panel to offer the electrical power injected into the lithium battery. However, this high charging efficiency is depended on the remaindering power of the battery. The high charging efficiency of 85% can be obtained at the initial empty battery. As prolonged the charging time, the charging efficiency is going decreased.

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Graphene oxide/Pt composite counter electrodes (CEs) are prepared for dye-sensitized solar cells (DSCs). The composite CE provides a higher efficiency of reaction of redox couple. Based on this approach, the DSCs with a lower loading of Pt CEs can be achieved.

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We reported a chemical treatment which could passivate the defects of CuIn1-xGaxSe2 (CIGS) film by immersing the thin film in trioctylphosphine sulfide (TOP:S) solution. By means of photoluminescence (PL) measurements, PL intensity of CIGS thin film increased with TOP:S passivation.

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in this work, we demonstrated an organic solar cell with C60/ boron subphthalocyanine (SubPc) (acceptor/donor) inverted structure. Electrical and optical characteristics were demonstrated with different thicknesses of molybdenum trioxide (MoO3) hole-extracting layer.

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Chemical bath deposition was employed to deposit Cu2ZnSnS4 (CZTS) films, which were sulfurized by ditert-butylsulfide (DTBS) in an atmospheric pressure quartz reactor at 400~600°C. Increments of sulfurization time interval or DTBS admittance enable the formation of CZTS structure. The characteristics of CZTS under various sulfurization conditions are addressed.

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In this report, we demonstrate the relationship between charge transfer states and open-circuit voltage (VOC) in small-molecule organic photovoltaic devices. It is found that the VOC not only depends on the interface gap between donor and acceptor but also the injection property and donor/acceptor interfacial area.

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By stacking InGaAs quantum dots layers of different compositions, we can increase the broadband absorption range near photon energy = 1eV. The broadband quantum dots solar cell consists of consists of 3 different QDs, and each QD has 3 layers. The short circuit current is improved about 124% by the growth of ZnO nanorods array on the surface of solar cell.

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ZnO nanorods were synthesized by a two-step approach in this study. The ZnO films as a seed layer were deposited on the glass by sol-gel. The ZnO nano-particle seed solution was spin coated onto FTO glass substrates.Different morphologies of ZnO nanorods demonstrated by different growth time.efficiency of 0.347% were obtained.

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The H2 plasma passivation was used to improve the efficiency of amorphous silicon (a-Si) solar cells. The efficiency of H2 plasma-passivated a-Si solar cells fabricated on glass substrate increased to 4.22 %. Finally, the a-Si solar cell with efficiency of 3.27 % was successfully fabricated on plastic substrate.

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This study proposes the inorganic phosphor used in the luminescent solar concentrator (LSC) for the luminescent material. It was found that the re-emitting light escaping from the escape cone would be a serious problem for the use of LSC and should be solved. It was also found that the re-emitting light escaped from the rear surface more than the light from the side surfaces.

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We demonstrate a promising structure and key factors to achieve high-efficiency hybrid heterojunction solar cells, which can facilitate the device performance. By using the multi-textured pyramid/silicon nanowire (SiNW) to achieve low reflection and designing hole-transporting layer (HTL), the device performance is enhanced to 11.5%.

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A new cathode buffer layer is developed for the use in organic photovoltaic devices. Besides the thickness-independent electrical effects, the injection efficiency is also increased. The window of thickness tuning of this new cathode buffer is in a range of 8-24 nm, indicating the potential use in optical spacer.

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The anti-reflection behavior of multilayer polyelectrolyte on thin film solar cell is investigated. The cationic and anionic polyelectrolyte deposited with layer by layer self-assembly method proved effective in enhancing the anti-reflectivity and quantum efficiency of the thin film solar cell.

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Coating profiles of PEDOT:PSS on Si nanowires (SiNWs) are improved by Zonyl fluorosurfactant treated PEDOT:PSS. After treatment, SiNW/PEDOT:PSS solar cells generate higher PCE of 10.87%, Jsc of 28.86 mA/cm2, and FF of 71.75%. Comparatively, the control devices have lower PCE of 9.55%, Jsc of 28.04 mA/cm2, and FF of 63.57%.

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In this research, we use two-step process to form perovskite CH3NH3PbI3 on planar ZnO thin layer. The whole process is completed under low temperature. The best device has high Jsc of 20 mA/cm2 and efficiency of 13.3% due to uniform morphology of ZnO film and appropriate control of two-step process.

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In this report, we composite PEDOT:PSS and carbon black as counter electrodes to replace the conventional platinum electrodes in DSSCs. By controlling the thickness of PEDOT:PSS film, JSC were increase obviously. After mixed PEDOT:PSS with carbon black, the fill-factor and thus the device efficiency were improved in further.

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To obtain high-quality In0.16Ga0.84As epitaxial films, we designed the step graded or linear graded buffer layer on the GaAs substrate before growing the InGaAs epilayer. The conversion efficiencies of In0.16Ga0.84As solar cells with step graded and linear graded buffer layers were measured to 14.8% and 16.6%, respectively.

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In this work, we study the lifetime of dye sensitized solar cells (DSSCs). The performances of the device under air atmosphere were measured and discussed. The device performances could be recovered partially after re-injecting the electrolyte. The un-reversible part of device efficiency could be attributed to degradation of the dye.

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In this project, an advanced solar simulator was developed. The superior properties of the simulator can meet the requirements of production lines of new generation photovoltaic (PV) modules. It is expected to take the place of existing products on the market. By using the light propagation and flexibility of optical fibers, the energy of light source is distributed onto the illuminated area uniformly, enabling the flash solar simulator to test efficiency of PV modules on production lines. On the illuminated area of 2m x 1.5m, the irradiance is needed to be at least 1000W/m2. Spectral match, non-uniformity, and temporal instability of the simulator are better than the definition of A class by IEC60904-9. Especially, the spectrum matches AM1.5G from 300nm, making the testing results of PV modules more actual and precise. A high speed IV tracer was also developed in this project. The IV tracer can perform IV curve measurements within a pulse (10ms), and parameters such as Pmax, Isc, and F.F. are figured out as well.

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This article is to study how the electrochemical deposition of copper oxide deposit as a solar cell applications, and the only way to explain this is deduced special IV Solar energy level graph model.

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