共查询到20条相似文献,搜索用时 15 毫秒
1.
F. Yakuphanoglu 《Solar Energy》2011,85(11):2704-2709
Boron doped CdO thin films were prepared by sol–gel dip coating technique. Atomic force microscopy results indicate that the boron doped CdO films have the nanostructure. The influence of the boron doping on the film growth is resulted in a change of grain size. The optical band gap of the CdO films was significantly changed by boron dopant. The refractive index dispersion of the films obeys the single oscillator model. The dispersion parameters, oscillator and dispersion energy were changed by boron dopant. The optical absorption results show that the optical band gap of the CdO film can be engineered over a wide range of 2.27–2.45 eV by introducing B dopant. For solar cell applications of the CdO film, a p-Si/1% B doped n-CdO heterojunction solar cell was fabricated and the solar cell shows the best values of open circuit voltage, Voc = 0.37 and short circuit current density, Jsc = 0.81 mA/cm2 under AM1.5 illumination, despite the fact that Voc and Jsc are lower than those reported in the literature without using frontal grid contacts and or post-deposition annealing. It is evaluated that this work is useful as a basis search for synthesis of the nanosized-boron doped cadmium oxide thin films for solar cell applications and more competitive p-Si/n-CdO based solar cells. 相似文献
2.
CdO and Cu2O thin films have been grown on glass substrates by chemical deposition method. Optical transmittances of the CdO and Cu2O thin films have been measured as 60–70% and 3–8%, respectively in 400–900 nm range at room temperature. Bandgaps of the CdO and Cu2O thin films were calculated as 2.3 and 2.1 eV respectively from the optical transmission curves. The X-ray diffraction spectra showed that films are polycrystalline. Their resistivity, as measured by Van der Pauw method yielded 10−2–10−3 Ω cm for CdO and approximately 103 Ω cm for Cu2O. CdO/Cu2O solar cells were made by using CdO and Cu2O thin films. Open circuit voltages and short circuit currents of these solar cells were measured by silver paste contacts and were found to be between 1–8 mV and 1–4 μA. 相似文献
3.
TiO2-overcoated SnO2:F transparent conductive oxide films were prepared by atmospheric pressure chemical vapor deposition (APCVD) and an effect of TiO2 layer thickness on a-Si solar cell properties was investigated. The optical properties and the structure of the TiO2 films were evaluated by spectroscopic ellipsometry and X-ray difractometry. a-Si thin film solar cells were fabricated on the SnO2:F films over-coated with TiO2 films of various thicknesses (1.0, 1.5 and 2.0 nm) and I–V characteristics of these cells were measured under 1 sun (100 mW/cm2 AM-1.5) illumination. It was found that the TiO2 film deposited by APCVD has a refractive index of 2.4 at 550 nm and anatase crystal structure. The conversion efficiency of the a-Si solar cell fabricated on the 2.0 nm TiO2-overcoated SnO2:F film increased by 3%, which is mainly attributed to an increase in open circuit voltage (Voc) of 30 mV. 相似文献
4.
Thin films of cadmium oxide (CdO) were synthesized by layer-by-layer deposition method on indium doped tin oxide (ITO) substrates. Post-deposition annealing at 250 °C for 24 h produced pure phase CdO films by removal of trace amount of cadmium hydroxide, as confirmed from X-ray diffractogram. First time employment of CdO in place of TiO2 in dye-sensitized solar cells is reported to check feasibility and cell performance. A dye-sensitized nanocrystalline CdO photo-electrode was obtained by adsorbing cis-dithiocyanato (4,4′-dicarboxylic acid-2,2′-bipyridide) ruthenium (II) (N3) dye by keeping at 45 °C for 20 h. The efficiency of dye-sensitized nanocrystalline CdO thin film solar cell was increased from 0.24% to 2.95% due to dye adsorption. This must be highest reported conversion efficiency for other metal oxides than TiO2based dye-sensitized solar cells. 相似文献
5.
Kensuke Nishioka Nobuhiro Sakitani Yukiharu Uraoka Takashi Fuyuki 《Solar Energy Materials & Solar Cells》2007,91(13):1222-1227
We proposed a modified 3-diode equivalent circuit model for analysis of multicrystalline silicon (Mc-Si) solar cells. By using this equivalent circuit model, we can precisely evaluate the characteristics of Mc-Si solar cells taking the influence of grain boundaries and large leakage current through the peripheries into consideration and extract electrical properties. The calculated value of current-voltage characteristics for small size (3 mm×3 mm) Mc-Si solar cells using this model completely agreed with the measured value at various cell temperatures. Moreover, the calculated open-circuit voltage (Voc) obtained by extracted parameters and measured Voc agreed well. 相似文献
6.
Mohamad Rusop Tetsuo Soga Takashi Jimbo 《Solar Energy Materials & Solar Cells》2006,90(18-19):3214-3222
The phosphorus-doped amorphous carbon (n-C:P) films were grown by r.f. power-assisted plasma-enhanced chemical vapor deposition at room temperature using solid phosphorus target. The influence of phosphorus doping on material properties of n-C:P based on the results of simultaneous characterization are reported. Moreover, the solar cell properties such as series resistance, short circuit current density (Jsc), open circuit current voltage (Voc), fill factor (FF) and conversion efficiency (η) along with the spectral response are reported for the fabricated carbon based n-C:P/p-Si heterojunction solar cell were measured by standard measurement technique. The cells performances have been given in the dark I–V rectifying curve and I–V working curve under illumination when exposed to AM 1.5 illumination condition (100 mW/cm2, 25 °C). The maximum of Voc and Jsc for the cells are observed to be approximately 236 V and 7.34 mA/cm2, respectively for the n-C:P/p-Si cell grown at lower r.f. power of 100 W. The highest η and FF were found to be approximately 0.84% and 49%, respectively. We have observed the rectifying nature of the heterojunction structures is due to the nature of n-C:P films. 相似文献
7.
This article reports the preparation of three-dimensional (3D) mesoporous zinc oxide (ZnO) films and their application in solar cells. The films were obtained through electrochemical deposition in DMSO solutions by using PS colloidal crystal as templates. The ZnO films with inverse opal (IO) structure were obtained after removing the templates by thermolysis. The ordered porous ZnO films were used to prepare hybrid solar cells by infiltrating the films with poly(3-hexylthiophene) (P3HT) or P3HT:ZnO nanocomposite. Results showed that the interpenetrating network of both ZnO(IO) and P3HT can form continuous pathways for electron and hole transport. By infiltrating a P3HT:ZnO nanocomposite into the porous ZnO films, the photocurrent of the solar cell can be dramatically improved. The cell shows the Voc and Isc of 462 mV and 444.3 μA/cm2, respectively. By using a 420 nm cutoff filter, the cell retains about 80% and 50% of its original Voc and Isc after continuous white-light illumination (100 mW/cm2) for 10 h. Stability of the device under above conditions was estimated to be 51 h. 相似文献
8.
Jeong Chul Lee Ki Hwan Kang Seok Ki Kim Kyung Hoon Yoon I Jun Park Jinsoo Song 《Solar Energy Materials & Solar Cells》2000,64(2):185
Transparent ZnO films were prepared by rf magnetron sputtering, and their electrical, optical, and structural properties were investigated under various sputtering conditions. Aluminum-doped n-type(n-ZnO) and undoped intrinsic-ZnO (i-ZnO) layers were deposited on a glass substrate by incorporating different targets in the same reaction chamber. The n-ZnO films were strongly affected by argon ambient pressure and substrate temperature, and films deposited at 2 mTorr and 100°C showed superior properties in resistivity, transmission, and figure of merit (FOM). The sheet resistance of ZnO film was less dependent on film thickness when the substrate was heated during deposition. These positive effects of elevated substrate temperature are presumably attributed to the rearrangement of the sputtered atoms by the heat energy. Also, the films are electrically uniform through the 5 cm×5 cm substrate. The maximum deviation in sheet resistance is less than 10%. All of the films showed strong (0 0 2) diffraction peak near 2θ =34°. The undoped i-ZnO films deposited in the mixture of argon and oxygen gases showed high transmission properties in the visible range, independent of the Ar/O2 ratio, while resistivity rose with increased oxygen partial pressure. The Cu(In,Ga)Se2 solar cells, incorporating bi-layer ZnO films (n-ZnO/i-ZnO) as window layer, were finally fabricated. The fabricated solar cells showed 14.48% solar efficiency under AM 1.5 conditions (100 mW/cm2). 相似文献
9.
P. Kumar D. Bhusari D. Grunsky M. Kupich B. Schroeder 《Solar Energy Materials & Solar Cells》2006,90(18-19):3345-3355
We report on boron-doped μc-Si:H films prepared by hot-wire chemical vapor deposition (HWCVD) using silane as a source gas and trimethylboron (TMB) as a dopant gas and their incorporation into all-HW amorphous silicon solar cells. The dark conductivity of these films was in the range of 1–10 (Ω cm)−1. The open circuit voltage Voc of the solar cells was found to decrease from 840 mV at low hydrogen dilution H-dil=91% to 770 mV at high H-dil =97% during p-layer deposition which can be attributed to the increased crystallinity at higher H-dil and to subsequent band edge discontinuity between μc-Si:H p- and amorphous i-layer. The short circuit current density Jsc and the fill factor FF show an optimum at an intermediate H-dil and decrease for the highest H-dil. To improve the conversion efficiency and the reproducibility of the solar cells, an amorphous-like seed layer was incorporated between TCO and the bulk p-layer. The results obtained until now for amorphous solar cells with and without the seed layer are presented. The I–V parameters for the best p–i–n solar cell obtained so far are Jsc=13.95 mA/cm2, Voc=834 mV, FF=65% and η=7.6%, where the p-layers were prepared with 2% TMB. High open circuit voltages up to 847 mV could be achieved at higher TMB concentrations. 相似文献
10.
The phosphorus-doped amorphous carbon (n-C:P) films were grown by radiofrequency (RF) power-assisted plasma-enhanced chemical vapor deposition (PECVD) at room temperature using a solid phosphorus target. The influence of phosphorus doping on the material properties of n-C:P based on the results of simultaneous characterization are reported. Moreover, solar cell properties such as series resistance, short-circuit current density, open-circuit current voltage, fill factor and conversion efficiency along with the spectral response are reported for the fabricated carbon-based n-C:P/p-Si heterojunction solar cells by standard measurement technique. The cells’ performances have been given in the dark I–V rectifying curve and I–V working curve under illumination when exposed to AM 1.5 illumination condition (100 mW/cm2, 25 °C). The maximum open-circuit voltage (Voc) and short-circuit current density (Jsc) for the cells are observed to be approximately 236 V and 7.34 mA/cm2, respectively, for the n-C:P/p-Si cell grown at a lower RF power of 100 W. The highest energy conversion efficiency (η) and fill factor (FF) were found to be approximately 0.84% and 49%, respectively. We have observed that the rectifying nature of the heterojunction structures is due to the nature of n-C:P films. 相似文献
11.
H. Tabet-Derraz N. Benramdane D. Nacer A. Bouzidi M. Medles 《Solar Energy Materials & Solar Cells》2002,73(3)
ZnxCd1−xO thin films were prepared on glass substrates by spray pyrolysis technique. The precursor solutions were obtained by varying the concentration of Zn(NO3)2·6H2O and Cd(NO3)2·4H2O in bi-distilled water. The structural properties have been studied using X-ray diffraction spectra. All the structures include the basic compounds, i.e. ZnO and CdO. The orientation and the crystalline phases of the deposited films were specified. With the addition of Zn to the precursor solution, we can observe the preferential orientation of the CdO in the [2 0 0] direction. The electrical measurements were performed using method of four contacts. Thin films transmittances, in the 1.5–4.3 eV range, for different compositions have been measured and the optical gaps have been determined. The variations are explained considering the gaps of the two pure films. The influence of increased Cd concentration in the films on the structural, electrical and optical properties is investigated in this study. 相似文献
12.
Satoshi Shimizu Akihisa Matsuda Michio Kondo 《Solar Energy Materials & Solar Cells》2008,92(10):1241-1244
In this study, highly stabilized hydrogenated amorphous silicon films and their solar cells were developed. The films were fabricated using the triode deposition system, where a mesh was installed between the cathode and the anode (substrate) in a plasma-enhanced chemical vapor deposition system. At a substrate temperature of 250 °C, the hydrogen concentration of the resulting film (Si–H=4.0 at%, Si–H2<1×1020 cm−3) was significantly less than that of conventionally prepared films. The films were used to develop the i-layers of solar cells that exhibited a significantly low degradation ratio of 7.96%. 相似文献
13.
Al and Y codoped ZnO (AZOY) transparent conducting oxide (TCO) thin films were first deposited on n-Si substrates by pulsed laser deposition (PLD) to form AZOY/n-Si heterojunction solar cells. However, the properties of the AZOY emitter layers are critical to the performance of AZOY/n-Si heterojunction solar cells. To estimate the properties of AZOY thin films, films deposited on glass substrates with various substrate temperatures (Ts) were analyzed. Based on the experimental results, optimal electrical properties (resistivity of 2.8 ± 0.14 × 10?4 Ω cm, carrier mobility of 27.5 ± 0.55 cm2/Vs, and carrier concentration of 8.0 ± 0.24 × 1020 cm?3) of the AZOY thin films can be achieved at a Ts of 400 °C, and a high optical transmittance of AZOY is estimated to be >80% (with glass substrate) in the visible region under the same Ts. For the AZOY/n-Si heterojunction solar cells, the AZOY thin films acted not only as an emitter layer material, but also as an anti-reflected coating thin film. Thus, a notably high short-circuit current density (Jsc) of 31.51 ± 0.186 mA/cm2 was achieved for the AZOY/n-Si heterojunction solar cells. Under an AM1.5 illumination condition, the conversion efficiency of the cells is estimated at only approximately 4% (a very low open-circuit voltage (Voc) of 0.24 ± 0.001 V and a fill factor (FF) of 0.51 ± 0.011) without any optimization of the device structure. 相似文献
14.
Kensuke Takechi Tohru Shiga Tomoyoshi Motohiro Tsuyoshi Akiyama Sunao Yamada Hideki Nakayama Keiichi Kohama 《Solar Energy Materials & Solar Cells》2006,90(9):1322-1330
Wet-type organic solar cells containing 5,10,15,20-3-tetrathienylporphyrin (TThP) and polythiophene (PTh) films were fabricated. The TThP/PTh film was prepared on indium-tin-oxide (ITO) glass using an electrochemical polymerization method in an n-Bu4NPF6/CH2Cl2 solution. It was found that a small amount of iodine doping of the film improved the incident photon-to-electron conversion efficiency (IPCE) of a solar cell consisting of a TThP/PTh film and an aqueous electrolyte. A HOMO level measurement suggested that a modified HOMO level of the low iodine-doped TThP/PTh film allowed a fast electron transfer from PTh to a porphyrin moiety. To obtain further improvement, a sandwich-type solar cell using a 5% (w/w) aqueous solution of acetonitrile containing 0.05 M iodine and 0.5 M lithium iodide as an electrolyte was then fabricated. The solar cell absorbed light in the 300–800 nm wavelength range, converting this to a cathodic photocurrent with a maximum IPCE of 32% at 430 nm under irradiation of 5.0×1014 photon cm−2 s−1. This value is about 10 times higher than that of the solar cells using an aqueous electrolyte. The total energy conversion efficiency (η) of the solar cell under simulated sunlight reached 0.12% for 2.59 mW cm−2 at AM1.5 and 0.05% for 100 mW cm−2 at air mass 1.5. 相似文献
15.
TiO2 thin films as protective material for transparent-conducting oxides used in Si thin film solar cells 总被引:1,自引:0,他引:1
H. Natsuhara K. Matsumoto N. Yoshida T. Itoh S. Nonomura M. Fukawa K. Sato 《Solar Energy Materials & Solar Cells》2006,90(17):2867-2880
Nb-doped TiO2 films have been fabricated by RF magnetron sputtering as protective material for transparent-conducting oxide (TCO) films used in Si thin film solar cells. It is found that TiO2 has higher resistance against hydrogen radical exposure, utilizing the hot-wire CVD (catalytic CVD) apparatus, compared with SnO2 and ZnO. Further, the minimum thickness of TiO2 film as protective material for TCO was experimentally investigated. Electrical conductivity of TiO2 in the as-deposited film is found to be 10−6 S/cm due to the Nb doping. Higher conductivity of 10−2 S/cm is achieved in thermally annealed films. Nitrogen treatments of Nb-doped TiO2 film have been also performed for improvements of optical and electric properties of the film. The electrical conductivity becomes 4.5×10−2 S/cm by N2 annealing of TiO2 films at 500 °C for 30 min. It is found that the refractive index n of Nb-doped TiO2 films can be controlled by nitrogen doping (from n=2.2 to 2.5 at λ = 550 nm) using N2 as a reactive gas. The controllability of n implies a better optical matching at the TCO/p-layer interface in Si thin film solar cells. 相似文献
16.
Semiconducting cuprous oxide films were prepared by electrodeposition onto commercial conducting glass coated with indium tin oxide deposited by spraying technique. The cuprous oxide (Cu2O) films were deposited using a galvanostatic method from an alkaline CuSO4 bath containing lactic acid and sodium hydroxide at a temperature of 60°C. The film's thickness was about 4–6 μm. This paper includes discussion for Cu2O films fabrication, scanning electron microscopy and X-ray diffractometry studies, optical properties and experimental results of solar cells. The values of the open circuit voltage Voc of 340 mV and the short circuit current density Isc of 245 μA/cm2 for ITO/Cu2O solar cell were obtained by depositing graphite paste on the rear of the Cu2O layer. It should be stressed that these cells exhibited photovoltaic properties after heat treatment of the films for 3 h at 130°C. An electrodeposited layer of Cu2O offers wider possibilites for application and production of low cost cells, both in metal–semiconductor and hetero-junction cell structures, hence the need to improve the photovoltaic properties of the cells. 相似文献
17.
S.R. Jadkar J.V. Sali A.M. Funde Nabeel Ali Bakr P.B. Vidyasagar R.R. Hawaldar D.P. Amalnerkar 《Solar Energy Materials & Solar Cells》2007,91(8):714-720
Hydrogenated amorphous silicon (a-Si:H) thin films were deposited from pure silane (SiH4) using hot-wire chemical vapor deposition (HW-CVD) method. We have investigated the effect of substrate temperature on the structural, optical and electrical properties of these films. Deposition rates up to 15 Å s−1 and photosensitivity 106 were achieved for device quality material. Raman spectroscopic analysis showed the increase of Rayleigh scattering in the films with increase in substrate temperature. The full width at half maximum of TO peak (ΓTO) and deviation in bond angle (Δθ) are found smaller than those obtained for P-CVD deposited a-Si:H films. The hydrogen content in the films was found <1 at% over the range of substrate temperature studied. However, the Tauc's optical band gap remains as high as 1.70 eV or much higher. The presence of microvoids in the films may be responsible for high value of band gap at low hydrogen content. A correlation between electrical and structural properties has been found. Finally, the photoconductivity degradation of optimized a-Si:H film under intense sunlight was also studied. 相似文献
18.
Sn doped indium oxide (ITO) single layer films and ITO/Copper (Cu) bi-layer films were prepared on polycarbonate substrates by DC and RF magnetron sputtering without intentional substrate heating. In order to consider the influence of the Cu underlayer on the optoelectrical properties and microstructures of the films, the thickness of the Cu bottom layer in the ITO/Cu films was varied from 5 to 20 nm.Conventional ITO films had a constant optical transmittance of 74% and an electrical resistivity of 3.1 × 10−3 Ω cm, while ITO/Cu films had different optoelectrical properties that were influenced by the thickness of the Cu bottom layer. The lowest electrical resistivity, 5.7 × 10−5 Ω cm, was obtained from ITO 80 nm/Cu 20 nm films and the highest optical transmittance of 72%, was obtained from the ITO 95 nm/Cu 5 nm films. From the figure of merit (TC) which is defined by TC = T10/Rs, where T is the optical transmittance at 550 nm and Rs is the sheet resistance, it can be concluded that the most effective Cu thickness in the ITO/Cu films on the optoelectrical properties was 5 nm. 相似文献
19.
R. Mendoza-Prez J. Aguilar-Hernndez J. Sastre-Hernndez N. Ximello-Quiebras G. Contreras-Puente G. Santana-Rodríguez O. Vigil-Galn E. Moreno-García A. Morales-Acevedo 《Solar Energy》2006,80(6):682-686
In this work, we study CdS films processed by chemical bath deposition (CBD) using different thiourea concentrations in the bath solution with post-thermal treatments using CdCl2. We study the effects of the thiourea concentration on the photovoltaic performance of the CdS/CdTe solar cells, by the analysis of the I–V curve, for S/Cd ratios in the CBD solution from 3 to 8. In this range of S/Cd ratios the CdS/CdTe solar cells show variations of the open circuit voltage (Voc), the short circuit current (Jsc) and the fill factor (FF). Other experimental data such as the optical transmittance and photoluminescence were obtained in order to correlate to the I–V characteristics of the solar cells. The best performance of CdS–CdTe solar cells made with CdS films obtained with a S/Cd ratio of 6 is explained in terms of the sulfur vacancies to sulfur interstitials ratio in the CBD–CdS layers. 相似文献
20.
Giuseppe Calogero Jun-Ho Yum Alessandro Sinopoli Gaetano Di Marco Michael Grätzel Mohammad Khaja Nazeeruddin 《Solar Energy》2012,86(5):1563-1575
We present the photoelectrochemical properties of dye-sensitized solar cells using natural pigments containing betalains and anthocyanins as sensitizers. The dyes extracted from grape, mulberry, blackberry, red Sicilian orange, Sicilian prickly pear, eggplant and radicchio have shown a monochromatic incident photon to current efficiency (IPCE) ranging from 40% to 69%. Short circuit photocurrent densities (Jsc) up to 8.8 mA/cm2, and open circuit voltage (Voc) ranging from 316 to 419 mV, were obtained from these natural dyes under 100 mW/cm2 (AM 1.5) simulated sunlight. The best solar conversion efficiency of 2.06% was achieved with Sicilian prickly pear fruits extract. The influence of pH and co-absorbers on natural sensitizers, were investigated and discussed. 相似文献