Impact of maximum copper content during the 3-stage process on CdS thickness tolerance in Cu(In,Ga)Se2-based solar cell

ABSTRACTThe tolerance of photovoltaic performances of Cu(In,Ga)Se2-based (CIGSe) solar cells prepared from 3-stage grown absorbers to cadmium sulfide (CdS) buffer layer thickness was investigated. We focus on the influence of the maximum Cu content y = [Cu]/([In]+[Ga]) reached during the co-evaporation process on this tolerance. By increasing the duration of the 2nd stage we varied ymax from 0.93±0.11 up to 1.06±0.12. Although final Cu content and CIGSe surface morphology seem to be similar for all absorbers, the photovoltaic performance of cells with higher maximum Cu content are better; moreover they tolerate much thinner CdS buffers (down to 10 nm-thick) without open circuit voltage or fill factor loss. Cells with lower ymax exhibit more erratic performance and J(V,T) measurements show a specific voltage distribution for thin CdS. From these results it appears possible to decrease the CdS buffer layer thickness if it is deposited on adapted absorbers.

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Microcrystalline (Si,Ge):H Solar Cells

MRS Proceedings ◽

10.1557/proc-762-a7.6 ◽

2003 ◽

Vol 762 ◽

Cited By ~ 1

Author(s):

Jianhua Zhu ◽

Vikram L. Dalal

Keyword(s):

Solar Cells ◽

Buffer Layer ◽

Quantum Efficiency ◽

Fill Factor ◽

Open Circuit Voltage ◽

Defect Density ◽

Cell Structure ◽

Open Circuit ◽

Base Layer ◽

Ecr Plasma

AbstractWe report on the growth and properties of microcrystalline Si:H and (Si,Ge):H solar cells on stainless steel substrates. The solar cells were grown using a remote, low pressure ECR plasma system. In order to crystallize (Si,Ge), much higher hydrogen dilution (∼40:1) had to be used compared to the case for mc-Si:H, where a dilution of 10:1 was adequate for crystallization. The solar cell structure was of the p+nn+ type, with light entering the p+ layer. It was found that it was advantageous to use a thin a-Si:H buffer layer at the back of the cells in order to reduce shunt density and improve the performance of the cells. A graded gap buffer layer was used at the p+n interface so as to improve the open-circuit voltage and fill factor. The open circuit voltage and fill factor decreased as the Ge content increased. Quantum efficiency measurements indicated that the device was indeed microcrystalline and followed the absorption characteristics of crystalline ( Si,Ge). As the Ge content increased, quantum efficiency in the infrared increased. X-ray measurements of films indicated grain sizes of ∼ 10nm. EDAX measurements were used to measure the Ge content in the films and devices. Capacitance measurements at low frequencies ( ~100 Hz and 1 kHz) indicated that the base layer was indeed behaving as a crystalline material, with classical C(V) curves. The defect density varied between 1x1016 to 2x1017/cm3, with higher defects indicated as the Ge concentration increased.

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Side-chain effect on the photovoltaic performance of conjugated polymers based on benzodifuran and benzodithiophene-4,8-dione

MRS Advances ◽

10.1557/adv.2019.223 ◽

2019 ◽

Vol 4 (36) ◽

pp. 2001-2007

Author(s):

Enfang He ◽

Hong Zhang ◽

Yueyue Gao ◽

Fengyun Guo ◽

Shiyong Gao ◽

...

Keyword(s):

Fill Factor ◽

Open Circuit Voltage ◽

Polymer Solar Cells ◽

Photovoltaic Performance ◽

Open Circuit ◽

Side Chain ◽

Large Area ◽

Device Structure ◽

Roll To Roll ◽

Solvent Additive

ABSTRACT:Two benzodifuran (BDF) polymers, PBDF-C and PBDF-S, with alkyl and alkylthio substituted thiophene side-chains and benzodithiophene-4,8-dione (BDD) as the acceptor were designed and synthesized. Their optical, electrochemical properties and photovoltaic performances were systematically investigated. The polymer solar cells (PSCs) with a device structure of ITO/PEDOT:PSS/polymer:PC71BM/Ca/Al were fabricated. The PBDF-C based device showed a power conversion efficiency (PCE) of 3.01% after adding 1 vol% 1,8-diodooctane (DIO) as the solvent additive, and PBDF-S gave an enhanced PCE of 3.48% without any post-treatments. The enhancements were from the higher open-circuit voltage (Voc) and fill factor (FF). The thermal- and solvent-treatment-free processing is more favourable for the large area roll-to-roll manufacturing or printing technology for PSCs.

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Ultra-low p-doping of poly(3-hexylthiophene) and its impact on polymer aggregation and photovoltaic performance

Organic Photonics and Photovoltaics ◽

10.1515/oph-2016-0001 ◽

2016 ◽

Vol 4 (1) ◽

Cited By ~ 3

Author(s):

Marcel M. Said ◽

Yadong Zhang ◽

Raghunath R. Dasari ◽

Dalaver H. Anjum ◽

Rahim Munir ◽

...

Keyword(s):

Solar Cells ◽

Fill Factor ◽

Open Circuit Voltage ◽

Photovoltaic Performance ◽

Photovoltaic Cells ◽

Open Circuit ◽

Device Performance ◽

Long Range Order ◽

P3ht Film ◽

Low Levels

AbstractPoly(3-hexylthiophene) (P3HT) films and P3HT / fullerene photovoltaic cells have been p-doped with very low levels (< 1 wt. %) of molybdenum tris[1-(trifluoromethylcarbonyl)- 2-(trifluoromethyl)-ethane-1,2-dithiolene]. The dopants are inhomogenously distributed within doped P3HT films, both laterally and as a function of depth, and appear to aggregate in some instances. Doping also results in subtle changes in the local and long range order of the P3HT film. These effects likely contribute to the complexity of the observed evolutions in conductivity, mobility and work function with doping levels. They also negatively affect the open-circuit voltage and fill factor of solar cells in unexpected ways, indicating that dopant aggregation and non-uniform distribution can harm device performance.

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Fabrication of TiO2 Nanotubes Array by Anodization for DSSC

Materials Science Forum ◽

10.4028/www.scientific.net/msf.743-744.920 ◽

2013 ◽

Vol 743-744 ◽

pp. 920-925

Author(s):

Hong Zhou Yan ◽

Jun You Yang ◽

Shuang Long Feng ◽

Ming Liu ◽

Jiang Ying Peng ◽

...

Keyword(s):

Fill Factor ◽

Open Circuit Voltage ◽

Short Circuit ◽

Photovoltaic Performance ◽

Short Circuit Current ◽

Short Circuit Current Density ◽

Open Circuit ◽

Tetrabutyl Titanate ◽

X Ray Diffraction ◽

X Ray

TiO2 nanotubes array was fabricated by anodization. Effect of reaction duration on the morphology of TiO2 nanotube arrays was studied detailedly. The structure and morphology of the prepared nanotubes array was characterized by X-ray diffraction and scanning electron microscopy, respectively. The fabricated TiO2 arrays were peeled off and adhered to FTO glass with adhesive (mixture of tetrabutyl titanate and polyethylene glycol), then they were sintered at 450 for photoanode of DSSC. The photovoltaic performance of the prepared sample as the DSSC anode was investigated. An open circuit voltage of 0.69V and a short circuit current density of 7.78mA/cm2 were obtained, and the fill factor and the convert efficiency were 0.517 and 2.78%, respectively.

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Improved fill factor and open circuit voltage by crystalline selenium at the Cu(In,Ga)Se2 /buffer layer interface in thin film solar cells

Progress in Photovoltaics Research and Applications ◽

10.1002/pip.957 ◽

2010 ◽

Vol 18 (4) ◽

pp. 249-256 ◽

Cited By ~ 10

Author(s):

C. Platzer-Björkman ◽

P. Zabierowski ◽

J. Pettersson ◽

T. Törndahl ◽

M. Edoff

Keyword(s):

Thin Film ◽

Solar Cells ◽

Buffer Layer ◽

Fill Factor ◽

Open Circuit Voltage ◽

Open Circuit ◽

Thin Film Solar Cells ◽

Layer Interface

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Dependence of material properties and photovoltaic performance of triple cation tin perovskites on the iodide to bromide ratio

Monatshefte für Chemie - Chemical Monthly ◽

10.1007/s00706-019-02503-6 ◽

2019 ◽

Vol 150 (11) ◽

pp. 1921-1927 ◽

Cited By ~ 1

Author(s):

Stefan Weber ◽

Thomas Rath ◽

Birgit Kunert ◽

Roland Resel ◽

Theodoros Dimopoulos ◽

...

Keyword(s):

Material Properties ◽

Fill Factor ◽

Open Circuit Voltage ◽

Short Circuit ◽

Photovoltaic Performance ◽

Short Circuit Current ◽

Short Circuit Current Density ◽

Open Circuit ◽

X Ray Diffraction ◽

X Ray

Abstract In this work, the influence of a partial introduction of bromide (x = 0–0.33) into MA0.75FA0.15PEA0.1Sn(BrxI1−x)3 (MA: methylammonium, FA: formamidinium, PEA: phenylethylammonium) triple cation tin perovskite on the material properties and photovoltaic performance is investigated and characterized. The introduction of bromide shifts the optical band gap of the perovskite films from 1.29 eV for the iodide-based perovskite to 1.50 eV for the perovskite with a bromide content of x = 0.33. X-ray diffraction measurements reveal that the size of the unit cell is also gradually reduced based on the incorporation of bromide. Regarding the photovoltaic performance of the perovskite films, it is shown that already small amounts of bromide (x = 0.08) in the perovskite system increase the open circuit voltage, short circuit current density and fill factor. The maximum power conversion efficiency of 4.63% was obtained with a bromide content of x = 0.25, which can be ascribed to the formation of homogeneous thin films in combination with higher values of the open circuit voltage. Upon introduction of a higher amount of bromide (x = 0.33), the perovskite absorber layers form pinholes, thus reducing the overall device performance. Graphic abstract

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Simultaneous improvement of three parameters using a binary processing solvent system approach in as-cast non-fullerene solar cells

Journal of Materials Chemistry A ◽

10.1039/c9ta10887d ◽

2019 ◽

Vol 7 (45) ◽

pp. 25978-25984 ◽

Cited By ~ 4

Author(s):

Guoming Qin ◽

Lianjie Zhang ◽

Dong Yuan ◽

Haiying Jiang ◽

Wei Tang ◽

...

Keyword(s):

Solar Cells ◽

System Approach ◽

Fill Factor ◽

Open Circuit Voltage ◽

Short Circuit ◽

Photovoltaic Performance ◽

Short Circuit Current ◽

Solvent System ◽

Open Circuit ◽

Binary Solvent

A binary solvent approach simultaneously improves the open-circuit voltage, short-circuit current, and fill factor, and finally elevates the as-cast photovoltaic performance.

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Comparison of Prolonged Light Soaking of Single and Stacked Junction A-SI:H Solar Cells

MRS Proceedings ◽

10.1557/proc-149-583 ◽

1989 ◽

Vol 149 ◽

Cited By ~ 3

Author(s):

P. Lechner ◽

B. Scheppat ◽

R. Geyer ◽

H. Rübel ◽

M. Gorn ◽

...

Keyword(s):

Solar Cells ◽

Layer Thickness ◽

Fill Factor ◽

Open Circuit Voltage ◽

Prolonged Exposure ◽

Single Cells ◽

Open Circuit ◽

Si Solar Cells ◽

Extended Exposure ◽

Interface Effects

ABSTRACTLight-induced degradation of a-Si solar cells is dependent on their design. The degradation rate for single cells increases with i-layer thickness. Very thin i-layer devices (d < 100 nm) exhibit a delayed onset of degradation which is accompanied by a severe loss of open circuit voltage at prolonged exposure times. By extrapolating i-layer thickness to zero and therefore separating bulk and interface effects, the latter may account for a substantial loss of stability. The introduction of a SiC buffer layer at the p/i interface results in a considerable higher degradation mainly caused by a loss in fill factor.Double stacked cells, as compared to single cells having similar initial efficiences, show higher stability. The instability at extended exposure times of very thin single cells as used in a tandem configuration did not influence the stacked device.

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