A cell-based PBM for continuous open-circuit dry milling: Impact of axial mixing, nonlinear breakage, and screen size

Porous aluminium doped TiO2 was prepared through a sol–gel process in the presence of a template. The doping enlarges the band-gap of the anatase TiO2, which modifies the TiO2 electrical properties. The porous Al/TiO2 films were assembled into dye-sensitized solar cells. A 45 mV enhancement of open-circuit photovoltage and 11% increase of fill factor at 2 wt-% doping concentration, and 8.6% improvement of the overall efficiency at 0.5 wt-% doping concentration were achieved relative to that of a cell containing non-doped TiO2 under the same conditions. This advance is attributed to the increase in conductivity with the Al-doping of the TiO2 electrode.

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Micro-Raman Studies of Mixed-phase Hydrogenated Silicon Solar Cells

MRS Proceedings ◽

10.1557/proc-762-a4.5 ◽

2003 ◽

Vol 762 ◽

Cited By ~ 17

Author(s):

Jessica M. Owens ◽

Daxing Han ◽

Baojie Yan ◽

Jeffrey Yang ◽

Kenneth Lord ◽

...

Keyword(s):

Solar Cells ◽

Direct Evidence ◽

Amorphous Material ◽

Equivalent Circuit Model ◽

Open Circuit ◽

Mixed Phase ◽

Silicon Solar Cells ◽

Heterogeneous Structure ◽

Hydrogenated Silicon ◽

A Cell

AbstractThe open-circuit voltage (Voc) of mixed-phase hydrogenated silicon solar cells has been found to increase after light soaking. In this study, we use micro-Raman to investigate the heterogeneous structure of solar cells in the amorphous-to-nanocrystalline transition region. For a cell with Voc = 0.981 V, Raman spectra show a typical broad Gaussian lineshape around 480 cm-1, a signature of typical amorphous material. A cell with Voc = 0.674 V displays a sharp Lorentzian peak around 516 cm-1, indicative of nanocrystallinity. A cell with Voc = 0.767 V was systematically scanned for 20 different positions in 500 μm increments. Most spectra show a typical Gaussian lineshape around 480 cm-1, several spectra reveal a hint of a nanocrystalline shoulder around 512 cm-1, and one spectrum exhibits a distinct nanocrystalline peak. We conclude that the nanocrystallite distribution in the mixed-phase material is very non-uniform even within a mm dot. This result provides direct evidence supporting a recently proposed two-diode equivalent-circuit model to explain the light-induced effect.

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Numerical Simulations of Carrier-selective Contact Silicon Solar Cells: Role of Surface Passivation and Carrier-Selective Layers Electronic Properties

10.21203/rs.3.rs-491788/v1 ◽

2021 ◽

Author(s):

KRISHNA SINGH ◽

Dipak Kumar Singh ◽

Vamsi K. Komarala

Keyword(s):

Work Function ◽

Open Circuit Voltage ◽

Surface Passivation ◽

Inversion Layer ◽

Open Circuit ◽

Rear Side ◽

Cell Structures ◽

Strong Inversion ◽

A Cell

Abstract Ag/ITO/MoOx/n-Si/LiFx/Al carrier-selective contact (CSC) solar cell structures are modelled and numerically simulated based on the experimental data using an industrial quality base silicon wafer by the Sentaurus TCAD software. The role of (1) electron-selective lithium fluoride (LiFx) layer and its thickness, (2) hole-selective molybdenum oxide (MoOx) work function variation, and (3) front contact (MoOx/n-Si) surface passivation interlayer are explored on the device performance. The electron-selective LiFx layer at the rear side is led to the strong enhancement in device photocurrent by providing the electrical barrier to the minority carriers (holes) and slight improvement in open-circuit voltage, but the thickness of the layer is sensitive to efficient extraction of the majority carriers (electrons). The hole-selective MoOx layer work function needs to engineer for inducing the strong inversion layer with better built-in potential at the MoOx/n-Si junction to achieve high open-circuit voltage from a cell. A thin SiOx interlayer at the MoOx/n-Si junction has enhanced the device open-circuit voltage significantly by minimizing the minority carrier recombination at the interface.

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How do Buffer Layers Affect Solar Cell Performance and Solar Cell Stability?

MRS Proceedings ◽

10.1557/proc-668-h6.9 ◽

2001 ◽

Vol 668 ◽

Cited By ~ 11

Author(s):

Bolko von Roedern

Keyword(s):

Solar Cells ◽

Solar Cell ◽

Carrier Transport ◽

Open Circuit ◽

Operating Conditions ◽

Cell Performance ◽

Buffer Layers ◽

Limiting Current ◽

Solar Cell Performance ◽

A Cell

ABSTRACTBuffer layers are commonly used in the optimization of thin-film solar cells. For CuInSe2-and CdTe-based solar cells, multilayer transparent conductors (TCOs, e.g., ZnO or SnO2) are generally used in conjunction with a CdS heterojunction layer. Optimum cell performance is usually found when the TCO layer in contact with the CdS is very resistive or almost insulating. In addition to affecting the open-circuit voltage of a cell, it is commonly reported that buffer layers affect stress-induced degradation and transient phenomena in CdTe- and CuInSe2-based solar cells. In amorphous silicon solar cells, light-induced degradation has a recoverable and a nonrecoverable component too, and the details of the mechanism may depend on the p-type contact layer. Because of the similarity of transients and degradation in dissimilar material systems, it is suggested that degradation and recovery are driven by carriers rather than by diffusing atomic species. The question that must be addressed is why, not how, species diffuse and atomic configurations relax differently in the presence of excess carriers. In this paper, I suggest that the operating conditions of a cell can change the carrier transport properties. Often, excess carriers may enhance the conductance in localized regions (“filaments”) and buffer layers; limiting current flow into such filaments may therefore control the rate and amount of degradation (or recovery).

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Effect of Bandgap Grading on the Performance of a-Si1-xGex:H Single-Junction Thin-Film Solar Cells

MRS Proceedings ◽

10.1557/opl.2011.928 ◽

2011 ◽

Vol 1321 ◽

Author(s):

H. J. Hsu ◽

C. M. Wang ◽

C. H. Hsu ◽

C. C. Tsai

Keyword(s):

Solar Cells ◽

Silicon Germanium ◽

Potential Gradient ◽

Open Circuit ◽

Hole Transport ◽

Single Junction ◽

Cell Efficiency ◽

A Cell ◽

20 Nm ◽

Amorphous Silicon Germanium

ABSTRACTIn this work, the effect of bandgap grading of hydrogenated amorphous silicon germanium (a-Si1-xGex:H) absorber near the p/i and the i/n interfaces was investigated. The a-Si1-xGex:H single-junction solar cells were improved by applying both p/i grading and i/n grading. Our results showed that both the p/i and the i/n grading can increase the open-circuit voltage (VOC) as compared to the cell without grading. The i/n grading can further improve the FF. Presumably the potential gradient created by the i/n grading can facilitate the hole transport thus it can improve the FF. However, the JSC decreased as the i/n grading width increased. The reduction of JSC was due to the loss in the red response, which can be attributed to the replacement of lower bandgap material by the larger ones. Combining the effects of VOC, JSC and FF, a suitable thickness of the p/i and the i/n grading was 20 nm and 45 nm, respectively. Finally, the grading structures accompanied with further optimization of doped layers were integrated to achieve a cell efficiency of 8.59 %.

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A Simple, Membrane-Free, Direct Glycerol Fuel Cell Utilizing a Precious Metal-Free Cathode and Gold-Plated Anode Surfaces

Energies ◽

10.3390/en11092259 ◽

2018 ◽

Vol 11 (9) ◽

pp. 2259 ◽

Cited By ~ 5

Author(s):

Yi Tseng ◽

Daniel Scott

Keyword(s):

Fuel Cells ◽

Fuel Cell ◽

Crude Glycerol ◽

Open Circuit Voltage ◽

Open Circuit ◽

Low Grade ◽

Gold Plating ◽

A Cell ◽

Alkaline Membrane ◽

Diesel Production

As bio-diesel production continues around the world, the amount of low-grade glycerol, a byproduct from the process, in increasing, as is the demand for a simple, easy-to-make, fuel cell capable of running off glycerol and oxygen from the air. Despite the research that has already been done with glycerol fuel cells, the complexity of the fuel cell designs for such a simple fuel appears to be prohibitive toward the actualization of such a cell. Here the simplest of fuel cells, an alkaline, membrane-free, glycerol fuel cell with a non-platinum-containing MnO2 cathode is explored. Glycerol oxidation is catalyzed on various surfaces including carbon felt, platinum, and silver-plated nickel with and without gold plating. The maximum power this glycerol fuel cell generates, with 1.4 M glycerol and 8.0 M KOH, is 1.27 mW cm−2 at 200 mV. It has an open circuit voltage of 704 mV. Additionally, the effects of different, gold-plated anodic surfaces, electrolytes and temperatures are also explored. This work demonstrates the feasibility of this simple, reusable robust cell design using pure and crude glycerol from bio-diesel production and preliminarily explores the products of this reaction.

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Open-Circuit Voltage Physics in Amorphous Silicon Solar Cells

MRS Proceedings ◽

10.1557/proc-609-a18.3 ◽

2000 ◽

Vol 609 ◽

Cited By ~ 32

Author(s):

L. Jiang ◽

J. H. Lyou ◽

S. Rane ◽

E. A. Schiff ◽

Q. Wang ◽

...

Keyword(s):

Solar Cells ◽

Open Circuit Voltage ◽

Thermionic Emission ◽

Open Circuit ◽

Silicon Solar Cells ◽

Band Offset ◽

Model Calculations ◽

Conduction Band Offset ◽

A Cell ◽

Computer Calculations

ABSTRACTWe have performed computer calculations to explore effects of the p/i interface on the open-circuit voltage in a-Si:H based pin solar cells. The principal conclusions are that interface limitation can occur for values of VOC significantly below the built-in potential VBI of a cell, and that the effects can be understood in terms of thermionic emission of electrons from the intrinsic layer into the p-layer. We compare measurements of VOC and electroabsorption estimates of VBI with the model calculations. We conclude that p/i interface limitation is important for current a-Si:H based cells, and that the conduction band offset between the p and i layers is as important as the built-in potential for future improvements to VOC.

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Electronic device for microelectrode recordings in epithelial cells

AJP Cell Physiology ◽

10.1152/ajpcell.1984.246.3.c339 ◽

1984 ◽

Vol 246 (3) ◽

pp. C339-C346 ◽

Cited By ~ 23

Author(s):

J. F. Garcia-Diaz ◽

S. Stump ◽

W. M. Armstrong

Keyword(s):

Continuous Monitoring ◽

Electronic Device ◽

Voltage Drop ◽

Membrane Damage ◽

Open Circuit ◽

Salt Bridges ◽

Current Pulses ◽

A Cell ◽

Tip Potential ◽

The Individual

A device is described that permits continuous measurement of electrophysiological parameters in epithelial tissues in the open-circuit mode. Transepithelial potential (VT) and microelectrode (either conventional or ion-selective) potential (VM) are directly measured. Application of transepithelial current pulses allows continuous monitoring of transepithelial resistance (RT) and the ratio between the changes in VM and VT induced by these pulses. Measurement of this ratio, which under some circumstances reflects the apical fractional resistance of the cellular pathway, is important in assessing membrane damage during microelectrode impalement and/or as an index that the microelectrode tip is inside a cell. This is particularly useful when the change in VM during impalement is small. Application of 0.5-nA current pulses through open-tip microelectrodes allows continuous recording of the microelectrode resistance (RM). In epithelia where the individual cells are electrically coupled this permits acceptable impalements (RM remains nearly constant) to be distinguished from those affected by tip potential artifacts due to plugging of the microelectrode tip (RM increases after penetration of the cell membrane). The device provides compensation for the IR voltage drop in the solution between the potential measuring salt bridges and the epithelial surfaces. The microelectrode electrometer has an input impedance greater than 10(15) and is provided with stray capacitance neutralization.

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Constitution and mechanism of the selenium rectifier photocell

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1950.0112 ◽

1950 ◽

Vol 202 (1071) ◽

pp. 449-466 ◽

Cited By ~ 36

Keyword(s):

Zinc Oxide ◽

Surface Film ◽

Cadmium Oxide ◽

Internal Resistance ◽

Open Circuit ◽

Intimate Contact ◽

Selenium Rectifier ◽

High Illumination ◽

A Cell ◽

Physical And Chemical

This paper describes experiments to elucidate the exact physical and chemical structure of the selenium rectifier photocell, especially that of the thin surface film. A technique is described for sputtering films of cadmium oxide which, though transparent in the thickness required for a cell, have an electrical conductivity exceeding that of graphite. The thickness of the films can be closely controlled. With such films, on pure crystalline selenium, cells were produced with white-light sensitivities of over 700 µA per lumen, open-circuit voltages up to 0.5 V under high illumination, and maximum quantum efficiencies up to 70 %. The optical properties of the films are described, and the way in which the technique may be used to produce other non-metallic films is indicated. The cadmium oxide is found to have a negative Hall coefficient, and is therefore an N type semi-conductor. Further experiments with single films of gold, and double films of zinc oxide and gold, illustrate the behaviour of these, in intimate contact with selenium. The metal-selenium contact yields a poor photocell, the metal-zinc oxide-selenium contact one whose properties are critically dependent on the thickness of the intermediate oxide layer, and the N type cadmium oxide-selenium contact one for which the efficiency is high, and the thickness of cadmium oxide not critical. It is suggested therefore that in the practical photocell, the essential mechanism is a contact between two suitable semi-conductors of dissimilar types, any extra metal film when present serving simply to raise the lateral conductivity of the intermediate semi-conducting film when this is not high enough to eliminate undesirable effects of a high internal resistance in the finished cell.

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A COMPOSITE ELECTROLYTE FOR AN SOFC CONSISTING OF A CERIA SHEET AND A ZIRCONIA FILM DEPOSITED BY THE SOL-GEL METHOD

MRS Proceedings ◽

10.1557/proc-496-185 ◽

1997 ◽

Vol 496 ◽

Cited By ~ 1

Author(s):

Reiichi Chiba ◽

Fumikatsu Yoshimura ◽

Junichi Yamaki

Keyword(s):

Sol Gel ◽

Open Circuit ◽

Cubic Phase ◽

X Ray Diffraction ◽

Composite Electrolyte ◽

Gel Method ◽

Sol Gel Method ◽

Zirconia Film ◽

Gel Film ◽

A Cell

ABSTRACTWe investigated a composite electrolyte for solid oxide fuel cells prepared by coating a ceria sheet (Ce0.8Gd0.2O2-d or GDC ) with a scandia alumina doped zirconia (0.850ZrO2-0.110Sc2O3-0.04Al2O3) film by the sol-gel method. The sol-gel film annealed at 1200°C was examined by X-ray diffraction analysis and found to be in a cubic phase at room temperature. The ionic conductivity of this film is comparable to that of bulk sintered at 1620°C. Scanning electron microscope observations revealed that the film forms a good interface with the electrolyte of the ceria sheet, even though the annealing temperature is as low as 1200°C.We fabricated a single cell consisting of a composite electrolyte, a La0.8Sr0.2MnO3 cathode and a Ni-YSZ anode. The composite electrolyte consisted of zirconia film about one micron thick deposited by the sol-gel method and a 0.2 mm thick ceria sheet.A cell operated with moist H2 and O2 gas exhibited an open circuit voltage of 1.00 V at 800°C. This value is much closer to the value of 1.13 V expected from the Nernst equation than the value of 0.76 V for a cell with a ceria sheet but without the sol-gel film.

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