共查询到20条相似文献,搜索用时 34 毫秒
1.
R. A. AbdelRassoul 《Renewable Energy》2001,23(3-4)
The current–voltage characteristics of solar cells, under illumination and in the dark, represent a very important tool for characterizing the performance of the solar cell.The PC-1D computer program has been used to analyze the deviation of the dark current–voltage characteristics of p–n junction silicon solar cells from the ideal two-diode model behavior of the cell, namely the appearance of “humps” in the I–V characteristics. The effects of the surface recombination velocity, the minority-carrier lifetimes in the base — and emitter regions of the solar cell, as well as the temperature dependence of the I–V characteristics have been modeled using PC-1D.It is shown that the “humps” in the I–V characteristics arise as a result of recombination within the space-charge region of the solar cell, occurring when conditions for recombination are different from the simple assumptions of the Sah–Noyce–Shockley theory. 相似文献
2.
In this work, quercetin/p-InP heterojunction solar cell has been fabricated via solution-processing method and characterized by current–voltage and capacitance–voltage measurements at room temperature. A barrier height and an ideality factor value of 0.86 eV and 3.20 for this structure in dark have been obtained from the forward bias current–voltage characteristics. From the capacitance–voltage measurement, the barrier height and free carrier concentration values for the quercetin/p-InP device have been calculated as 1.63 eV and 3.8×1017 cm−3, respectively. Also, series resistance calculation has been performed by using Cheung theory. The device exhibits a strong photovoltaic behavior with a maximum open circuit voltage Voc of 0.36 V and short-circuit current Isc of 35.3 nA under 120 lx light intensity only. 相似文献
3.
T. Wada Y. Hashimoto S. Nishiwaki T. Satoh S. Hayashi T. Negami H. Miyake 《Solar Energy Materials & Solar Cells》2001,67(1-4)
CIGS films were treated in In–S aqueous solution for high-efficiency CIGS solar cells. The In–S aqueous solution contained InCl3 and CH3CSNH2 (thioacetamide). The In–S treatment modified the CIGS surface favorably for high-efficiency CIGS solar cells as evidenced by the increase in Voc, Jsc and FF. The In–S treatment formed thin CuInS2 layer on the CIGS surface which contributes to the high efficiency and stable performance of the CIGS solar cell. The best cell showed an efficiency of 17.6% (Voc=0.649 V, Jsc=36.1 mA/cm2 and FF=75.1%) without any annealing and light soaking before I–V measurement. 相似文献
4.
Electronic and photovoltaic properties of Al/p-Si/copper phthalocyanine photodiode junction barrier 总被引:1,自引:0,他引:1
Al/p-Si/copper phthalocyanine photovoltaic device has been fabricated and characterised by current–voltage and capacitance–voltage measurements. Electrical properties of the device were determined by current–voltage characterizations under dark and illumination conditions. The density distribution of the interface states of the photodiode was found to vary from 8.88×1012 eV−1 cm−2 in Ess-0.54 eV to 4.51×1012 eV−1 cm−2 in Ess-0.61 eV. The device shows a photovoltaic behaviour with a maximum open circuit voltage Voc of 0.16 V and short-circuits current Isc of 0.45 μA under 3500 lux light intensity. 相似文献
5.
The effect of temperature on the charge transport and transient absorption properties of K27 sensitized DSSC 总被引:1,自引:1,他引:0
Kasim Ocakoglu Fahrettin Yakuphanoglu James R. Durrant Siddik Icli 《Solar Energy Materials & Solar Cells》2008,92(9):1047-1053
The charge transport and transient absorption properties of K27 dye-sensitized solar cell have been investigated. The current–voltage (I–V) characteristics of the solar cell were analyzed by the thermionic emission theory. The ideality factor, barrier height and series resistance values of the solar cell were determined. The ideality factor higher than unity indicated the presence of non-ideal behavior in current–voltage characteristics at lower voltages. At the higher voltages, the charge transport mechanism for the solar cell is controlled by a space-charge limited current (SCLC) with an exponential distribution of traps. The built potential values are determined from capacitance–voltage plot and were found to be 0.14 and 0.58 V, respectively. The transient absorption data of K27 DSSC device suggest that the fast and slow phases are taking place. While the fast phase corresponds to regeneration of the dye cation by the iodide redox couple, the slow phase corresponds to the decay of long-lived I2−/ TiO2 electron absorption. The best conversion efficiency for K27 DSSC was found to be 0.317% under 100 mW/cm2 (FF=0.584, Voc=480 mV, Isc=1.131 mA). The photocurrent results indicate that the photogeneration of charge carriers is a monophotonic process. 相似文献
6.
《Solar Energy Materials & Solar Cells》2005,85(3):345-358
Dark and illuminatied current–voltage (I–V) characteristics of Al/SiOx/p-Si metal–insulator–semiconductor (MIS) solar cells were measured at room temperature. In addition to capacitance–voltage (C–V) and conductance–voltage (G–V), characteristics are studied at a wide frequency range of 1 kHz–10 MHz. The dark I–V characteristics showed non-ideal behavior with an ideal factor of 3.2. The density of interface states distribution profiles as a function of (Ess−Ev) deduced from the I–V measurements at room temperature for the MIS solar cells on the order of 1013 cm−2 eV−1. These interface states were responsible for the non-ideal behavior of I–V, C–V and G–V characteristics. Frequency dispersion in capacitance for MIS solar cells can be interpreted only in terms of interface states. The interface states can follow the a.c. signal and yield an excess capacitance, which depends on the relaxation time of interface states and the frequency of the a.c. signal. It was observed that the excess capacitance Co caused by an interface state decreases with an increase of frequency. The capacitances characteristics of MIS solar cells are affected not only in interface states but also series resistance. Analysis of this data indicated that the high interface states and series resistance leads to lower values of open-circuit voltage, short-circuit current density, and fill factor. Experimental results show that the location of interface states and series resistance have a significant effect on I–V, C–V and G–V characteristics. 相似文献
7.
Photovoltaic (PV) system designers use performance data of PV modules to improve system design and make systems more cost effective. The collection of this valuable data is often not done due to the high costs associated with data acquisition systems. In this paper, we report on the design of a low-cost current–voltage (I–V) measuring system used to monitor the I–V characteristics of PV modules. Results obtained from monitoring seven crystalline silicon modules between October 2001 and November 2002 are presented and discussed. Results obtained also show the value of being able to continuously monitor the current–voltage characteristics of PV modules. 相似文献
8.
Manjunatha Pattabi Sheeja Krishnan Ganesh Sanjeev 《Solar Energy Materials & Solar Cells》2007,91(15-16):1521-1524
The current transport mechanisms of n+–p silicon (Si) photo-detectors in different temperature and bias regions before and after irradiation with a dose of 350 kGy has been investigated and presented in this article. Temperature-dependent dark current–voltage (I–V) studies under forward and reverse bias were carried out for this purpose. In the temperature range studied, the dark current contribution in the low bias range is believed to be due to the generation-recombination of minority carriers in the space-charge region. Electron irradiation does not seem to have altered the dark current conduction mechanism. Capacitance–voltage (C–V) at various temperatures was measured to identify the presence of deep levels in the device. 相似文献
9.
An accurate and fast method to calculate the efficiency of Cu(In,Ga)Se2 (CIGS) and CdTe thin-film solar modules is presented here. This comprises a new method to calculate the fill factor as a function of discrete and distributed series resistance, and of shunt conductance: a three-dimensional, third-order polynomial approximation is presented, and the expansion of the coefficients as a power series of 1/Voc is given. Analytical expressions are presented which fit experimental data of the optical absorption in ZnO as a function of its thickness or sheet resistance. Together with a calculation outline of the series and shunt effects of the module integration, this constitutes a practical module design tool. This is illustrated with results of dependence of module efficiency on cell length, window and absorber sheet resistance, interconnect contact resistance, “softness” of the cell I–V curve, and absorber material (CIGS or CdTe). Optimal or critical values for these parameters are given. 相似文献
10.
Two types of silicon (Si) substrates (40 n-type with uniform base doping and 40 n/n+ epitaxial wafers) from the silicon industry rejects were chosen as the starting material for low-cost concentrator solar cells. They were divided into four groups, each consisting of 20 substrates: 10 are n/n+ and 10 are n substrates, and the solar cells were prepared for different diffusion times (45, 60, 75 and 90 min). The fabricated solar cells on n/n+ substrates (prepared with a diffusion time of 75 min) showed better parameters. In order to improve their performances, particularly the fill factor, 20 new solar cells on n/n+ substrates were fabricated using the same procedure (the diffusion time was 75 min)—but with four new front contact patterns. Investigation of current–voltage (I–V) characteristics under AM 1.5 showed that the parameters of these 20 new solar cells have improved in comparison to previous solar cells' parameters, and were as follows: open-circuit voltage (VOC=0.57 V); short circuit current (ISC=910 mA), and efficiency (η=9.1%). Their fill factor has increased about 33%. The I–V characteristics of these solar cells were also investigated under different concentration ratios (X), and they exhibited the following parameters (under X=100 suns): VOC=0.62 V and ISC=36 A. 相似文献
11.
A new structure of three cascade solar cells with graded band-gap layer on the base of GaAs–AlGaAs heterosystem is designed to decrease the thermal losses, arising as a result of absorption of short-wavelength radiation. These solar cells were created by combining liquid-phase epitaxy with gas-phase zinc diffusion technologies. In these structures multilayer cascade elements reduce losses, caused by generation of “hot” carriers and the upper graded band-gap layer improves the conversion of short-wavelength radiation. The cell structure exhibited high short-wavelength sensitivity and the following parameters (under 1-sun conditions): open-circuit voltage (Voc=1.03 V); short-circuit current (Isc=24.9 mA/cm2); fill factor (FF=0.74) and efficiency (η=22.3%). Therefore it can be successfully utilized as power supplies in high-located areas, and as sensors of ultra-violet radiation. 相似文献
12.
A.A.M. Farag E.A.A. El-Shazly M. Abdel Rafea A. Ibrahim 《Solar Energy Materials & Solar Cells》2009,93(10):1853-1859
In this work, the construction and photoelectrical characterization of p-type organic semiconductor oxazine (OXZ) in junction with n-type silicon semiconductor are presented. The Stokes shift between absorption and emission of oxazine was analyzed. The analysis of the spectral behavior of the absorption coefficient (α) of OXZ, in the absorption region revealed a direct transition, and the energy gap was estimated as 1.82 eV. From the current–voltage, I–V, measurements of the Au/OXZ/n-Si/Al heterojunction in the temperature range 300–375 K, characteristic junction parameters and dominant conduction mechanisms were obtained. This heterojunction showed a photovoltaic behavior with a maximum open circuit voltage, Voc, of 0.42 V, short-circuit current density, Jsc, of 3.25 mA/cm2, fill factor, FF, of 0.35 and power conversion efficiency, η, of 3.2% under 15 mW/cm2 white light illumination. 相似文献
13.
The influence of alkylaminopyridine additives on the performance of a bis(tetrabutylammonium)cis-bis(thiocyanato)bis(2,2′-bipyridine-4-carboxylic acid, 4′-carboxylate)ruthenium(II) dye-sensitized TiO2 solar cell with an I−/I3− redox electrolyte in acetonitrile was studied. The current–voltage characteristics were measured for more than 20 different alkylaminopyridines under AM 1.5 (100 mW/cm2). The alkylaminopyridine additives tested had varying effects on the performance of the cell. All the additives decreased the short circuit photocurrent density (Jsc), but increased the open-circuit photovoltage (Voc) of the solar cell. Molecular orbital calculations imply that the dipole moment of the alkylaminopyridine molecules influences the Jsc of the cell and that the size, solvent accessible surface area, and ionization energy all affect the Voc of the cell. The highest Voc of 0.88 V was observed in an electrolyte containing 4-pyrrolidinopyridine, which is comparable to the maximum Voc of 0.9 V for a cell consisting of TiO2 electrode and I−/I3− redox system. 相似文献
14.
Effect of temperature and electron irradiation on the I–V characteristics of Au/CdTe Schottky diodes
The results of the studies on the effect of temperature and 8 MeV electron irradiation on the current–voltage (I–V) characteristics of the Au/CdTe Schottky diodes are presented in this article. Schottky diodes were prepared by evaporating Au onto n-type CdTe films electrodeposited onto stainless steel substrates. The forward and reverse current–voltage characteristics of these diodes were studied as a function of temperature. The diodes were subjected to 8 MeV electron irradiation at various doses and their effect on the I–V characteristics was studied. Some intrinsic and contact properties such as barrier height, ideality factor, and series resistance were calculated from the I–V characteristics. Diode ideality factor of the junctions were greater than unity. The ideality factor and the series resistance Rs increase with decrease in temperature. The conduction seems to be predominantly due to thermionic emission–diffusion mechanism. The resistance was found to increase with increasing dose. The leakage current, ideality factor and barrier height were found to be unaffected by electron irradiation up to, a dose of about 40 kGy. 相似文献
15.
L. Kronik B. Mishori E. Fefer Y. Shapira W. Riedl 《Solar Energy Materials & Solar Cells》1998,51(1):1126
Surface photovoltage spectroscopy (SPS) has been used for quality control of ZnO/CdS/ Cu(In,Ga)Se2 (CIGS) thin-film solar cells. The results show that SPS makes it possible to detect “hard failures” following CIGS deposition, and both “hard” and “soft” failures following CdS deposition and following ZnO deposition. In addition, a semi-quantitative screening of CdS/CIGS and ZnO/CdS/CIGS samples is possible. Hence, SPS is suggested as a useful tool for in-line monitoring of CIGS-based solar cell production lines. Moreover, SPS is shown to yield important new information regarding CIGS-based solar cells: (a) A deep gap state is found in samples of superior performance. (b) As opposed to the CdS/CIGS structure, a marked decrease in the open-circuit voltage upon Na contamination in ZnO/CIGS structures is found. 相似文献
16.
Suresh Kumar Dhungel Jinsu Yoo Kyunghae Kim Somnath Ghosh Sungwook Jung Junsin Yi 《Renewable Energy》2008,33(2):282
Back surface passivation becomes a key issue for the silicon solar cells made with thin wafers. The high surface recombination due to the metal contacts can be lowered by reducing the back contact area and forming local back surface field (LBSF) in conjunction with the passivation with dielectric layer. About 3×10-7 m thick porous silicon (PS) layer with pore diameter mostly of 1×10-8–5×10-8 m was formed by chemical etching of silicon using the acidic solution containing hydrofluoric acid (HF), nitric acid (HNO3) and De-ionized water in the volume ratio 1:3:5 at 298 K for which etching time was kept constant for 360 s. Electrical properties of oxidized PS was studied through the current–voltage (I–V) and capacitance–voltage (C–V) characteristics of the metal–insulator–semiconductor (MIS) device in which the oxidized PS was used as an insulating layer and the results were further analyzed. The C–V curves of all the studies MIS devices showed the negative flatband voltage varying from -2 to , confirming that the oxidized layer of PS has fixed positive charge. 相似文献
17.
Adelmo Ortiz-Conde Francisco J. García Snchez Juan Muci 《Solar Energy Materials & Solar Cells》2006,90(3):352-361
We present a new method to extract the intrinsic and extrinsic model parameters of illuminated solar cells containing parasitic series resistance and shunt conductance. The method is based on calculating the Co-content function (CC) from the exact explicit analytical solutions of the illuminated current–voltage (I–V) characteristics. The resulting CC is expressed as a purely algebraic function of current and voltage from whose coefficients the intrinsic and extrinsic model parameters are then readily determined by bidimensional fitting. The procedure is illustrated by applying it to experimental and synthetic I–V characteristics and an analysis of the errors is presented. 相似文献
18.
Meng Ni Michael K.H. Leung Dennis Y.C. Leung K. Sumathy 《Solar Energy Materials & Solar Cells》2006,90(9):1331-1344
The porosity in a dye-sensitized solar cell (DSSC) can affect light absorption and electron diffusion that govern the overall electrical current–voltage (I–V) characteristics. In this research, two methods, namely, constant overlap and variable overlap, were developed to determine the connectivity of dye-sensitized TiO2 particles in high and low porosity levels, respectively. In turn, the light absorption coefficient α and the electron diffusion coefficient D were analytically derived in terms of the porosity P. Subsequently, the electron diffusion differential equation involving α and D was solved for the I–V output as a function of P. A parametric analysis showed that the optimal porosity was equal to 0.41 for maximum I–V output. The analytical results agree well with experimental data reported in the literature. Besides DSSC, the analytical model can be applied to predict the performance of solid-state DSSC as well as dye-sensitized photoelectrochemical cells applied to hydrogen production and water purification. 相似文献
19.
Hideki Hasegawa Taketomo Sato Seiya Kasai Boguslawa Adamowicz Tamotsu Hashizume 《Solar Energy》2006,80(6):629-644
Characterization methods and fundamental aspects of surface/interface states and recombination process in Si and III–V materials are reviewed. Various measurement considerations are pointed out for the conventional metal–insulator–semiconductor (MIS) capacitance–voltage (C–V) method, a contactless C–V method, and the microscopic scanning tunneling spectroscopy (STS) method, and general features of surface states are discussed. Surface states are shown to have U-shaped distributions of donor–acceptor continuum with a characteristic charge neutrality level, EHO. Rigorous simulation of dynamics of surface recombination process has shown that the effective surface recombination velocity, Seff, is not a constant of the surface, but its value changes by many orders of magnitude with the incident light intensity and the polarity and amount of fixed charge. From this, new methods of surface state characterization based on photoluminescence and cathodoluminescence are derived. Attempts to control surface states and Fermi level pinning at metal semiconductor interface and free surfaces of nano-structures are presented as efforts toward “nano-photovoltaics”. 相似文献
20.
The purpose of the present study was to develop a sufficiently good fit for the measured I–V curve of a PV module and array using only three easily measurable parameters: —the open-circuit voltage (Voc); —the short-circuit current (Isc); —the maximum power (Pm). With an additional three parameters (
;
;
) it is possible to describe any I–V curve, taking into account cell temperature T and solar radiation Q. This method has been tested on various solar array panels as well as on a single 10 cm dia. solar cell. The difference between the real curve and the proposed fit was found to be less than 3 percent for a fixed temperature and radiation and about 6 percent for various combinations of temperature and radiation. 相似文献