scholarly journals PERFORMANCE of HYDROGENATED a-Si:H SOLAR CELLS with DOWNSHIFTING COATING

2011 ◽  
Vol 1321 ◽  
Author(s):  
Bill Nemeth ◽  
Yueqin Xu ◽  
Haorong Wang ◽  
Ted Sun ◽  
Benjamin G. Lee ◽  
...  

ABSTRACTWe apply a thin luminescent downshifting (LDS) coating to a hydrogenated amorphous Si (a-Si:H) solar cell and study the mechanism of possible current enhancement. The conversion material used in this study converts wavelengths below 400 nm to a narrow line around 615 nm. This material is coated on the front of the glass of the a-Si:H solar cell with a glass/TCO/p/i/n/Ag superstrate configuration. The initial efficiency of the solar cell without the LDS coating is above 9.0 % with open circuit voltage of 0.84 V. Typically, the spectral response below 400 nm of an a-Si:H solar cell is weaker than that at 615 nm. By converting ultraviolet (UV) light to red light, the solar cell will receive more red photons; therefore, solar cell performance is expected to improve. We observe evidence of downshifting in reflectance spectra. The cell Jsc decreases by 0.13 mA/cm2, and loss mechanisms are identified.

2014 ◽  
Vol 1070-1072 ◽  
pp. 616-619
Author(s):  
Wen Bo Xiao ◽  
Jin Dai ◽  
Guo Hua Tu ◽  
Hua Ming Wu

The dye-sensitized solar cell performances influenced by radiant intensity and illuminated area in concentrating photovoltaic system are investigated experimentally and discussed theoretically. The results show that, under the same irradiated cells area, the short-circuit current is linearly increasing with the radiant intensity and the open-circuit voltage follows a logarithmic function of the radiant intensity. And, it is turned out that the short-circuit current and open-circuit voltage are obviously enhanced by increasing the illuminated cells surface area at the same radiant intensity. However, that growth trends will decline with an increase of the illuminated area. The reason is more defects involved in the process of increasing illumination area. All results can be interpreted using an equivalent circuit of a single diode model. A good agreement can be observed from the fitting curves. It is of great significance for current photovoltaic research.


2016 ◽  
Vol 4 (20) ◽  
pp. 7943-7949 ◽  
Author(s):  
Jingjing Chang ◽  
Hai Zhu ◽  
Juanxiu Xiao ◽  
Furkan Halis Isikgor ◽  
Zhenhua Lin ◽  
...  

The presence of excess PbI2 can affect the structure of perovskites and photovoltaic performance of perovskite solar cells. Increased open-circuit voltage could be achieved by introducing proper PbI2. However, shorter carrier lifetime and increased recombination and resistance were observed when an excess of PbI2 was used.


Crystals ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 609 ◽  
Author(s):  
Charith Jayathilaka ◽  
Loku Singgappulige Rosantha Kumara ◽  
Koji Ohara ◽  
Chulho Song ◽  
Shinji Kohara ◽  
...  

Cuprous oxide (Cu2O) homojunction thin films on Ti substrates were fabricated by an electrochemical deposition in which a p-Cu2O layer was deposited on an n-Cu2O layer by carefully controlled bath conditions. It was found that the open-circuit voltage of the homojunction solar cell was significantly influenced by the pH of the lactate bath. The variation of the pH was used to achieve the best possible crystal orientation for homojunctions. The crystallinity and morphology of the products were characterized by X-ray diffraction (XRD), high-energy x-ray diffraction (HEXRD), and scanning electron microscopy (SEM). The current density voltage (J-V) analysis showed that the sulfur treatment and annealing enhanced the photocurrent by ten-fold compared to the untreated and unannealed homojunction solar cell. X-ray photoelectron spectroscopy (XPS) studies confirmed that the sulfur treatment eliminated the surface CuO and formed a thin layer of CuS, which was very useful to make the front Ohmic contact. Transient measurements confirmed that the p-type Cu2O layer, which was subjected to sulfur treatment, significantly reduced the recombination, thus enhancing the efficiency of the solar cell. The best sulfur treated annealed Ti/n-Cu2O/p-Cu2O/Au solar cell produced an energy conversion efficiency of 2.64% with an open-circuit voltage of 490 mV and a short circuit current density of 12.8 mA cm−2 under AM 1.5 illumination.


2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Shigeru Yamada ◽  
Shinsuke Miyajima ◽  
Makoto Konagai

A fabrication process for silicon/silicon dioxide (Si/SiO2) superlattice microwire array solar cells was developed. The Si/SiO2 superlattice microwire array was fabricated using a microsphere lithography process with polystyrene particles. The solar cell shows a photovoltaic effect and an open-circuit voltage of 128 mV was obtained. The limiting factors of the solar cell performance were investigated from the careful observations of the solar cell structures. We also investigated the influence of the microwire array structure on light trapping in the solar cells.


2012 ◽  
Vol 260-261 ◽  
pp. 154-162
Author(s):  
S. Tobbeche ◽  
M.N. Kateb

In this work, we present the simulation results of the technological parameters and the electrical characteristics of a crystalline silicon n+pp+ solar cell, using two-dimension (2D) software, namely TCAD Silvaco (Technology Computer Aided Design). TCAD Silvaco Athena is used to simulate various stages of the technology manufacturing, while TCAD Silvaco Atlas is used for the simulation of the electrical characteristics and the spectral response of the solar cell. The J-V characteristics and the external quantum efficiency (EQE) are simulated under AM 1.5 illumination. The conversion efficiency(η)of 16.06% is reached and the other characteristic parameters are simulated: the open circuit voltage (Voc) is of 0.63 V, the short circuit current density (Jsc) equals 30.54 mA/cm² and the form factor (FF) is of 0.83 for the n+pp+ solar cell with a silicon nitride antireflection layer (Si3N4). In order to highlight the importance of the back surface field (BSF), a comparison between two cells, one without BSF (structure n+p), the other with one BSF (structure n+pp+), was made. By creating a BSF on the rear face of the cell the short circuit current density increases from 28.55 to 30.54 mA/cm2, the open circuit voltage from 0.6 to 0.63 V and the conversion efficiency from 14.19 to 16.06%. A clear improvement of the spectral response is obtained in wavelengths ranging from 0.65 to 1.1 µm for the solar cell with BSF.


Author(s):  
Jae-Hyung Wi ◽  
Won Seok Han ◽  
Woo-Jung Lee ◽  
Dae-Hyung Cho ◽  
Hye-Jung Yu ◽  
...  

2005 ◽  
Vol 865 ◽  
Author(s):  
Kent Price ◽  
Kevin Cooper ◽  
Chris Lacy

AbstractOpen-Circuit Voltage Decay (OCVD) is a common technique used to characterize numerous semiconductor devices. However, to the knowledge of the authors, the technique has not previously been applied to CdTe-based solar cells. We use a simple setup consisting of a function generator, rectifying diode, and digital oscilloscope to measure the dark open circuit voltage decay as a function of time across a CdTe solar cell. We find the decay to be described by the equation v(t) = v0 + A1exp (–t/τ1) + A2exp (–t/τ2) where v is the voltage, t is time, τ1 and τ2 are characteristic decay times, and A1, A2 and v0 are constants. The two characteristic decay times are on the order of 10 μs and 500 μs. The relative contribution of the two decay times depends on the magnitude of the initial applied voltage pulse. We will describe preliminary results on the correlation between the OCVD and solar cell performance, including the effects of light-soaking on OCVD behavior.


Energies ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 592
Author(s):  
Myeong Sang Jeong ◽  
Yonghwan Lee ◽  
Ka-Hyun Kim ◽  
Sungjin Choi ◽  
Min Gu Kang ◽  
...  

In the fabrication of crystalline silicon solar cells, the contact properties between the front metal electrode and silicon are one of the most important parameters for achieving high-efficiency, as it is an integral element in the formation of solar cell electrodes. This entails an increase in the surface recombination velocity and a drop in the open-circuit voltage of the solar cell; hence, controlling the recombination velocity at the metal-silicon interface becomes a critical factor in the process. In this study, the distribution of Ag crystallites formed on the silicon-metal interface, the surface recombination velocity in the silicon-metal interface and the resulting changes in the performance of the Passivated Emitter and Rear Contact (PERC) solar cells were analyzed by controlling the firing temperature. The Ag crystallite distribution gradually increased corresponding to a firing temperature increase from 850 ∘C to 950 ∘C. The surface recombination velocity at the silicon-metal interface increased from 353 to 599 cm/s and the open-circuit voltage of the PERC solar cell decreased from 659.7 to 647 mV. Technology Computer-Aided Design (TCAD) simulation was used for detailed analysis on the effect of the surface recombination velocity at the silicon-metal interface on the PERC solar cell performance. Simulations showed that the increase in the distribution of Ag crystallites and surface recombination velocity at the silicon-metal interface played an important role in the decrease of open-circuit voltage of the PERC solar cell at temperatures of 850–900 ∘C, whereas the damage caused by the emitter over fire was determined as the main cause of the voltage drop at 950 ∘C. These results are expected to serve as a steppingstone for further research on improvement in the silicon-metal interface properties of silicon-based solar cells and investigation on high-efficiency solar cells.


Sign in / Sign up

Export Citation Format

Share Document