Iodine Doping Studies on Nonannealed Perylene 3,4,9,10-Tetra Carboxylic Dianhydride/Cobalt Phthalocyanine Bulk Heterojunction Solar Cells

Perylene 3,4,9,10-tetra carboxylic dianhydride (PTCDA) thin films find a lot of optoelectronic applications. In this work, thin films of PTCDA were deposited using vacuum evaporation technique onto clean glass substrates and the variation in conductivity, optical bandgap and percentage transmission due to iodine doping for different time intervals are discussed. To study the doping effects on devices, organic solar cells based on cobalt phthalocyanine (CoPc)/PTCDA as active layers on indium tin oxide–coated glass substrates were fabricated and characterized to evaluate the solar cell parameters. It was found that doping with iodine considerably increases the power conversion efficiency of the solar cells.

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Ag Doped Zinc Tin Oxide as Cathode for Organic Photovoltaic Cells

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.209-211.1719 ◽

2012 ◽

Vol 209-211 ◽

pp. 1719-1722

Author(s):

Ming Guo Zhang ◽

Nan Hai Sun

Keyword(s):

Solar Cells ◽

Tin Oxide ◽

Organic Solar Cells ◽

Indium Tin Oxide ◽

Bulk Heterojunction ◽

Indium Tin Oxide Electrode ◽

Heterojunction Solar Cells ◽

Visible Part ◽

Cell Architecture ◽

Zinc Tin Oxide

A thin Ag layer embedded between layers of zinc tin oxide (ZTO) are compared to cells using an indium tin oxide electrode was investigated for inverted organic bulk heterojunction solar cells employing a multilayer electrode. ZTO/Ag/ ZTO (ZAZ) electrode is the preparation at room temperature, a high transparency in the visible part of the spectrum, and a very low sheet resistance comparable to treated ITO without the need for any thermal post deposition treatment as it is necessary for ITO. The In-free ZAZ electrodes exhibit a favorable work function of 4.3 eV and are shown to allow for excellent electron extraction even without a further interlayer. This renders ZAZ a perfectly suited bottom electrode for inverted organic solar cells with simplified cell architecture.

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Improving Performance of CIGS Solar Cells by Annealing ITO Thin Films Electrodes

International Journal of Photoenergy ◽

10.1155/2015/483147 ◽

2015 ◽

Vol 2015 ◽

pp. 1-8 ◽

Cited By ~ 4

Author(s):

Chuan Lung Chuang ◽

Ming Wei Chang ◽

Nien Po Chen ◽

Chung Chiang Pan ◽

Chung Ping Liu

Keyword(s):

Thin Films ◽

Optical Properties ◽

Solar Cells ◽

Indium Tin Oxide ◽

Copper Indium Gallium Diselenide ◽

Glass Substrates ◽

Ito Film ◽

Ito Thin Films ◽

Cigs Solar Cells ◽

Ito Films

Indium tin oxide (ITO) thin films were grown on glass substrates by direct current (DC) reactive magnetron sputtering at room temperature. Annealing at the optimal temperature can considerably improve the composition, structure, optical properties, and electrical properties of the ITO film. An ITO sample with a favorable crystalline structure was obtained by annealing in fixed oxygen/argon ratio of 0.03 at 400°C for 30 min. The carrier concentration, mobility, resistivity, band gap, transmission in the visible-light region, and transmission in the near-IR regions of the ITO sample were-1.6E+20 cm−3,2.7E+01 cm2/Vs,1.4E-03 Ohm-cm, 3.2 eV, 89.1%, and 94.7%, respectively. Thus, annealing improved the average transmissions (400–1200 nm) of the ITO film by 16.36%. Moreover, annealing a copper-indium-gallium-diselenide (CIGS) solar cell at 400°C for 30 min in air improved its efficiency by 18.75%. The characteristics of annealing ITO films importantly affect the structural, morphological, electrical, and optical properties of ITO films that are used in solar cells.

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Roll-to-Roll Fabrication of Bulk Heterojunction Plastic Solar Cells using the Reverse Gravure Coating Technique

MRS Proceedings ◽

10.1557/proc-1091-aa05-45 ◽

2008 ◽

Vol 1091 ◽

Cited By ~ 5

Author(s):

Daniel Tobjork ◽

Harri Aarnio ◽

Tapio Mäkelä ◽

Ronald Österbacka

Keyword(s):

Solar Cells ◽

Organic Solar Cells ◽

Bulk Heterojunction ◽

Acid Methyl Ester ◽

Ambient Air ◽

Plastic Substrate ◽

Heterojunction Solar Cells ◽

Coating Technique ◽

Roll To Roll ◽

Poly Styrene Sulfonate

AbstractThe roll-to-roll reverse gravure (RG) coating technique was used to produce thin homogeneous films (∼100 nm) for organic bulk heterojunction solar cells. The conducting polymer poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) and the active layer regioregular poly(3-hexylthiophene-2,5-diyl):[6,6]-phenyl-C61-butyric acid methyl ester (P3HT:PCBM) were successfully subsequently RG coated on an ITO covered plastic substrate in ambient air. Working solar cells were achieved after annealing and thermal evaporation of the top contact. The AM1.5 power conversion efficiency (PCE) of the RG coated organic solar cells was determined to 0.74% (at 100 mW/cm2). This was very similar to the results of a reference device that was spin coated on a glass substrate in a nitrogen glove box.

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Minimizing geminate recombination losses in small-molecule-based organic solar cells

Journal of Materials Chemistry C ◽

10.1039/c9tc00862d ◽

2019 ◽

Vol 7 (22) ◽

pp. 6641-6648

Author(s):

Rafael Sandoval-Torrientes ◽

Alexey Gavrik ◽

Anna Isakova ◽

Abasi Abudulimu ◽

Joaquín Calbo ◽

...

Keyword(s):

Solar Cells ◽

Small Molecule ◽

Organic Solar Cells ◽

Bulk Heterojunction ◽

Geminate Recombination ◽

Recombination Rates ◽

Heterojunction Solar Cells ◽

Bulk Heterojunction Solar Cells

Geminate recombination rates are successfully predicted for series of small-molecule bulk heterojunction solar cells applying the Marcus–Levich–Jortner equation.

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Efficiency Enhancement in Organic Solar Cells by Use of Cobalt Phthalocyanine (CoPc) Thin Films

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2020.17517 ◽

2020 ◽

Vol 20 (6) ◽

pp. 3703-3709 ◽

Cited By ~ 2

Author(s):

S. S. Rawat ◽

Ashish Kumar ◽

R. Srivastava ◽

C. K. Suman

Keyword(s):

Thin Films ◽

Solar Cells ◽

Energy Level ◽

Buffer Layer ◽

Organic Solar Cells ◽

Fill Factor ◽

Series Resistance ◽

Short Circuit ◽

Acid Methyl Ester ◽

Cobalt Phthalocyanine

Cobalt phthalocyanine (CoPc) nano thin films have been introduced as a hole buffer layer in organic solar cells with active layer of Poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM). The surface morphology and opto-electrical properties of the CoPc thin films have made it an applicable materials for organic solar cells. The nano-thin films of CoPc are continuously distributed over the studied area and the roughness are around 5 to 7 nm for all thickness. The dominant optical absorptions are in the visible range of wavelengths 500 to 800 nm. The CoPc buffer layer is suitable for energy level matching in energy level diagram and enhances the absorption spectrum as well, which facilitate the charge carrier generation, increases charge transport, decreases charge recombination, hence enhance the all device parameters short circuit current density (Jsc), open circuit voltage (Voc) and fill factor (FF). The solar cells efficiency increases by ˜70% and the fill factor increases by ˜45% in comparison to the standard cells. The increase in efficiency and the fill factors of the solar cells may also be attributed to the increasing of shunt and lowering the series resistance of the cells. The cole–cole plots of the devices may be modeled in electrical circuit as a single parallel resistance Rb and capacitance Cb network with a series resistance Rc.

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Near IR Sensitization of Organic Bulk Heterojunction Solar Cells: Towards Optimization of the Spectral Response of Organic Solar Cells

Advanced Functional Materials ◽

10.1002/adfm.200901473 ◽

2010 ◽

Vol 20 (2) ◽

pp. 338-346 ◽

Cited By ~ 229

Author(s):

Markus Koppe ◽

Hans-Joachim Egelhaaf ◽

Gilles Dennler ◽

Markus C. Scharber ◽

Christoph J. Brabec ◽

...

Keyword(s):

Solar Cells ◽

Organic Solar Cells ◽

Bulk Heterojunction ◽

Spectral Response ◽

Heterojunction Solar Cells ◽

Bulk Heterojunction Solar Cells ◽

Near Ir

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Flexible Organic Solar Cells: Nanoscale Phase Separation and High Photovoltaic Efficiency in Solution-Processed, Small-Molecule Bulk Heterojunction Solar Cells (Adv. Funct. Mater. 19/2009)

Advanced Functional Materials ◽

10.1002/adfm.200990086 ◽

2009 ◽

Vol 19 (19) ◽

pp. NA-NA ◽

Cited By ~ 1

Author(s):

Bright Walker ◽

Arnold B. Tamayo ◽

Xuan-Dung Dang ◽

Peter Zalar ◽

Jung Hwa Seo ◽

...

Keyword(s):

Solar Cells ◽

Phase Separation ◽

Small Molecule ◽

Organic Solar Cells ◽

Bulk Heterojunction ◽

Solution Processed ◽

Heterojunction Solar Cells ◽

Bulk Heterojunction Solar Cells ◽

Nanoscale Phase Separation ◽

Photovoltaic Efficiency

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Optimization of solution-processed oligothiophene:fullerene based organic solar cells by using solvent additives

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.4.77 ◽

2013 ◽

Vol 4 ◽

pp. 680-689 ◽

Cited By ~ 8

Author(s):

Gisela L Schulz ◽

Marta Urdanpilleta ◽

Roland Fitzner ◽

Eduard Brier ◽

Elena Mena-Osteritz ◽

...

Keyword(s):

Solar Cells ◽

Organic Solar Cells ◽

Bulk Heterojunction ◽

Solution Processed ◽

Heterojunction Solar Cells ◽

Force Microscopy ◽

Vacuum Technology ◽

Atomic Force ◽

Donor And Acceptor ◽

Conversion Efficiencies

The optimization of solution-processed organic bulk-heterojunction solar cells with the acceptor-substituted quinquethiophene DCV5T-Bu 4 as donor in conjunction with PC61BM as acceptor is described. Power conversion efficiencies up to 3.0% and external quantum efficiencies up to 40% were obtained through the use of 1-chloronaphthalene as solvent additive in the fabrication of the photovoltaic devices. Furthermore, atomic force microscopy investigations of the photoactive layer gave insight into the distribution of donor and acceptor within the blend. The unique combination of solubility and thermal stability of DCV5T-Bu 4 also allows for fabrication of organic solar cells by vacuum deposition. Thus, we were able to perform a rare comparison of the device characteristics of the solution-processed DCV5T-Bu 4 :PC61BM solar cell with its vacuum-processed DCV5T-Bu 4 :C60 counterpart. Interestingly in this case, the efficiencies of the small-molecule organic solar cells prepared by using solution techniques are approaching those fabricated by using vacuum technology. This result is significant as vacuum-processed devices typically display much better performances in photovoltaic cells.

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Deformation and Failure of Bendable Organic Solar Cells

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1132.116 ◽

2015 ◽

Vol 1132 ◽

pp. 116-124 ◽

Cited By ~ 1

Author(s):

Joseph Asare ◽

B. Agyei-Tuffour ◽

O.K. Oyewole ◽

G.M. Zebaze-Kana ◽

W.O. Soboyejo

Keyword(s):

Solar Cells ◽

Organic Solar Cells ◽

Indium Tin Oxide ◽

Bulk Heterojunction ◽

Acid Methyl Ester ◽

Visible Spectrum ◽

Optical Transmittance ◽

Hole Injection ◽

Deformation And Failure ◽

Organic Layers

This research investigates the effects of bending on the electrical, optical, structural and mechanical properties of flexible organic photovoltaic (OPV) cells. Bulk heterojunction organic solar cells were fabricated on Polyethylene terephthalate (PET) substrates using Poly-3-hexylthiophene: [6, 6]-phenyl-C61-butyric acid methyl ester (P3HT: PCBM) as the active layer and Poly (3, 4-ethylenedioxythiophene) Polystyrenesulfonate (PEDOT: PSS) as the hole injection layer. All the organic layers were deposited by spin coating while the Al cathode was vacuum thermally evaporated. The Indium Tin Oxide (ITO) anode has an average optical transmittance of 85% in the visible spectrum, a sheet resistivity of 60 ohms per square and an average surface roughness of 3nm. The relationship between the optoelectronic performance of the various device layers and the applied mechanical strains has been analyzed. The effects of stress and strain on the current-voltage characteristics of the device and its failure were modeled using the Abaqus software.

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