Extremely Thin Absorber Layers in Solid State Solar Cells

2004 ◽  
Vol 822 ◽  
Author(s):  
A. Bellaidi ◽  
K. Ernst ◽  
R. Könenkamp

AbstractWe report on recent progress in fabricating an inorganic solid state solar cell based on a nano-structured substrate with an extremely thin absorber, the so-called eta-cell. The cell uses HgCdTe as an absorber layer and TiO2 as a substrate. By adjusting the Hg/Cd ratio the conduction band edges in these two materials can be brought into alignment. This tuning provides an ideal tool to optimize the optical and electrical properties of the cell. In qualitative agreement with earlier work we find a band offset of 0.25 eV to give maximum transfer rates across the interface. The optimized cell has a short circuit current of 15 mA/cm2 and an open-circuit voltage of 0.6 V. We discuss the optical and electrical properties of the cell, and outline ideas to further improve the performance.

2011 ◽  
Vol 347-353 ◽  
pp. 3666-3669
Author(s):  
Ming Biao Li ◽  
Li Bin Shi

The AMPS-ID program is used to investigate optical and electrical properties of the solar cell of a-SiC:H/a-Si1-xGex:H/a-Si:H thin films. The short circuit current density, open circuit voltage, fill factor and conversion efficiency of the solar cell are investigated. For x=0.1, the conversion efficiency of the solar cell achieve maximum 9.19 % at the a-Si1-xGex:H thickness of 340 nm.


2013 ◽  
Vol 702 ◽  
pp. 123-127
Author(s):  
Wei Jei Tzeng ◽  
Mei Lun Wu ◽  
Li Jiaun Lin ◽  
Horng Yi Chang

The anodized TiO2nanotube arrays (TNAs) have a benefit to provide large surfaces and straight electron transmitting routes to the electrode. However, it is difficult to fulfill with solid state electrolytes or photosensitive materials into the long TiO2nanotubes. The substrate of Ti/wave-like TiO2was prepared by peel-off the TNAs. The In2S3buffer layer between wave-like TiO2and CuInS2determines the photosensitivity of the Ti/wave-like TiO2/In2S3/CuInS2thin structure. The In2S3and CuInS2are well-crystallized at 300oC. The CuInS2phase forms in In2S3layer due to Cu diffusion independent on the slight loss of sulfur. The CuInS2direct deposition on Ti/wave-like TiO2substrate can not exhibit photosensitivity. When CuInS2deposited on In2S3to form Ti/wave-like TiO2/In2S3/CuInS2structure, the short-circuit current and the open-circuit voltage increase with the thickness increase of In2S3layer while illuminated by 50 mW/cm2white light.


2018 ◽  
Vol 73 (10) ◽  
pp. 957-964 ◽  
Author(s):  
Xinxing Liu ◽  
Ruiting Hao ◽  
Qichen Zhao ◽  
Faran Chang ◽  
Yong Li ◽  
...  

AbstractThe Cu2ZnSnS4 (CZTS) thin films were fabricated by sulfurization of radiofrequency magnetron sputtered Cu–Zn–Sn–O (CZTO) precursors. Here, we extend recent works in the field of fabricating CZTO precursors by a new approach sputtering ZnO/Sn/Cu targets. The effects of one-step and two-step annealing processes applied for CZTO precursors on the structure, morphology, optical, and electrical properties were investigated systematically. The preannealing step of fundamental phase formation in the sulfurization process was also discussed. The two-step annealing process was found to affect the composition of element Sn slightly but significantly improved crystallinity, CZTS/Mo interfacial conditions, surface roughness, and electrical properties. The two-step annealed CZTS thin films had excellent optical and electrical properties with an optical band gap of 1.51 eV, a hole concentration of 2.4 × 1017 cm−3, and a hole mobility of 1.97 cm2/(V⋅s). In addition, the CZTS/Mo interface with small grains and voids were significantly improved. CZTS-based solar cell devices were successfully fabricated. The characteristics of current–voltage (J–V) curves indicated that short-circuit currents had a tendency to increase with the improvement of CZTS/Mo interface and surface morphology. As a result, the device based on two-step annealed CZTS thin films exhibited better performance with an open-circuit voltage of 553 mV, short-circuit current of 7.2 mA⋅cm−2, a fill factor of 37.8%, and a conversion efficiency of 1.51%.


1980 ◽  
Vol 239 (5) ◽  
pp. F412-F419 ◽  
Author(s):  
K. W. Beyenbach ◽  
B. M. Koeppen ◽  
W. H. Dantzler ◽  
S. I. Helman

In previous studies of isolated perfused distal tubules of Thamnophis spp., elevation of luminal [Na] from 16 to 150 mM resulted in a transient hyperpolarization of the open-circuit voltage, VToc. To characterize further this response, studies were done to examine the concurrent changes of the transepithelial resistance, RT. After elevation of luminal [Na] from 16 to 150 mM. the VToc increased sharply from a mean of 38.5 to 61.2 mV and the RT decreased from a mean of 22.3 to 15.8 k omega x cm. Thereafter, the VToc declined slowly below control values, and the RT increased well above control values. The short-circuit current calculated as VToc/RT changed in parallel with the VToc, increasing at first (from 1.8 to 4.1 microA/cm) and then falling to about 0.2 microA/cm. Luminal addition of 10(-5) M amiloride caused th VToc leads to 0 and the RT to increase during control and all phases of the transient. On the assumption that RT during amiloride perfusion is the same as the shunt resistance, Rs, the values of the transepithelial driving force, ENa, and its series resistance, RNa, were calculated. An analysis of the data in this way indicated that the principal changes in the epithelium could be attributed to alterations of the RNa and not the ENa or Rs.


2014 ◽  
Vol 625 ◽  
pp. 140-143
Author(s):  
Liow Kai Sing ◽  
Coswald Stephen Sipaut ◽  
Rachel Fran Mansa ◽  
Jedol Dayou

In this study, quasi-solid state electrolyte (QSE) was prepared by blending the polyethylene glycol (PEG) with molecular weight of 400, 4,4’-diphenylmethane diisocyanate (MDI), potassium iodide (KI) and iodine (I2) under a low reaction temperature (50oC) for two hours. QSEs with a different ratio of PEG to MDI were formulated. Adding 15 vol% of MDl into the QSE was found to give the highest open circuit voltage, short circuit current and energy conversion efficient, which were 360 mV, 0.077 mA/cm2 and 0.02% respectively.


Author(s):  
Mingqiang Zhong ◽  
Qin Feng ◽  
Changlai Yuan ◽  
Xiao Liu ◽  
Baohua Zhu ◽  
...  

AbstractIn this work, the (1−x)Bi0.5Na0.5TiO3-xBaNi0.5Nb0.5O3 (BNT-BNN; 0.00 ⩽ x ⩽ 0.20) ceramics were prepared via a high-temperature solid-state method. The crystalline structures, photovoltaic effect, and electrical properties of the ceramics were investigated. According to X-ray diffraction, the system shows a single perovskite structure. The samples show the normal ferroelectric loops. With the increase of BNN content, the remnant polarization (Pr) and coercive field (Ec) decrease gradually. The optical band gap of the samples narrows from 3.10 to 2.27 eV. The conductive species of grains and grain boundaries in the ceramics are ascribed to the double ionized oxygen vacancies. The open-circuit voltage (Voc) of ∼15.7 V and short-circuit current (Jsc) of ∼1450 nA/cm2 are obtained in the 0.95BNT-0.05BNN ceramic under 1 sun illumination (AM1.5G, 100 mW/cm2). A larger Voc of 23 V and a higher Jsc of 5500 nA/cm2 are achieved at the poling field of 60 kV/cm under the same light conditions. The study shows this system has great application prospects in the photovoltaic field.


Solar Energy ◽  
2021 ◽  
Vol 213 ◽  
pp. 198-210
Author(s):  
Ahsan Nadeem ◽  
Hadeed Ahmed Sher ◽  
Ali Faisal Murtaza ◽  
Nisar Ahmed

2017 ◽  
Vol 80 (1) ◽  
Author(s):  
Zainal Arifin ◽  
Sudjito Soeparman ◽  
Denny Widhiyanuriyawan ◽  
Suyitno Suyitno ◽  
Argatya Tara Setyaji

Natural dyes have attracted much researcher’s attention due to their low-cost production, simple synthesis processes and high natural abundance. However the dye-sensitized solar cells (DSSCs) based natural dyes have higher tendency to degradation. This article reports on the enhancement of performance and stability of dye-sensitized solar cells (DSSCs) using natural dyes. The natural dyes were extracted from papaya leaves by ethanol solvent at a temperature of 50 °C. Then the extracted dyes were isolated and modified into Mg-chlorophyll using column chromatography. Mg-chlorophyll was then synthesized into Fe-chlorophyll to improve stability. The natural dyes were characterized using ultraviolet-visible spectrometry, Fourier transform infrared spectroscopy, and cyclic voltammetry. The performance of DSSCs was tested using a solar simulator. The results showed the open-circuit voltage, the short-circuit current density, and the efficiency of the extracted papaya leaves-based DSSCs to be 325 mV, 0.36 mA/cm2, and 0.07%, respectively. Furthermore, the DSSCs with purified chlorophyll provide high open-circuit voltage of 425 mV and short-circuit current density of 0.45 mA/cm2. The use of Fe-chlorophyll for sensitizing the DSSCs increases the efficiency up to 2.5 times and the stability up to two times. The DSSCs with Fe-chlorophyll dyes provide open-circuit voltage, short-circuit current density, and efficiency of 500 mV, 0.62 mA/cm2, and 0.16%, respectively. Further studies to improve the current density and stability of natural dye-based DSSCs along with an improvement in the anchor between dyes and semiconducting layers are required.


2018 ◽  
Vol 9 ◽  
pp. 1802-1808 ◽  
Author(s):  
Katherine Atamanuk ◽  
Justin Luria ◽  
Bryan D Huey

The nanoscale optoelectronic properties of materials can be especially important for polycrystalline photovoltaics including many sensor and solar cell designs. For thin film solar cells such as CdTe, the open-circuit voltage and short-circuit current are especially critical performance indicators, often varying between and even within individual grains. A new method for directly mapping the open-circuit voltage leverages photo-conducting AFM, along with an additional proportional-integral-derivative feedback loop configured to maintain open-circuit conditions while scanning. Alternating with short-circuit current mapping efficiently provides complementary insight into the highly microstructurally sensitive local and ensemble photovoltaic performance. Furthermore, direct open-circuit voltage mapping is compatible with tomographic AFM, which additionally leverages gradual nanoscale milling by the AFM probe essentially for serial sectioning. The two-dimensional and three-dimensional results for CdTe solar cells during in situ illumination reveal local to mesoscale contributions to PV performance based on the order of magnitude variations in photovoltaic properties with distinct grains, at grain boundaries, and for sub-granular planar defects.


Inventions ◽  
2019 ◽  
Vol 4 (3) ◽  
pp. 45 ◽  
Author(s):  
Waleed I. Hameed ◽  
Baha A. Sawadi ◽  
Safa J. Al-Kamil ◽  
Mohammed S. Al-Radhi ◽  
Yasir I. A. Al-Yasir ◽  
...  

Prediction of solar irradiance plays an essential role in many energy systems. The objective of this paper is to present a low-cost solar irradiance meter based on artificial neural networks (ANN). A photovoltaic (PV) mathematical model of 50 watts and 36 cells was used to extract the short-circuit current and the open-circuit voltage of the PV module. The obtained data was used to train the ANN to predict solar irradiance for horizontal surfaces. The strategy was to measure the open-circuit voltage and the short-circuit current of the PV module and then feed it to the ANN as inputs to get the irradiance. The experimental and simulation results showed that the proposed method could be utilized to achieve the value of solar irradiance with acceptable approximation. As a result, this method presents a low-cost instrument that can be used instead of an expensive pyranometer.


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