Introduction Physics of Organic Solar Cells Research Prospects Reference
Organic Solar Cells
Rahul Dewan
Organic Electronics Course Presentation International University Bremen
4th May 2006
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Research Prospects Reference Outline
1 Introduction Solar Cells Organic Solar Cells
2 Physics of Organic Solar Cells Structure Working principle
3 Research Prospects Comparison Improving efficiency
4 Reference
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Solar Cells Research Prospects Organic Solar Cells Reference History of Solar Cell
Started with French scientist Edmond Becquerel’s photoelectric experiments in 1839. First solar cell using junctions was built by an American, Charles Fritts in 1883. (It was formed using coated selenium and gold, as a result, efficiency of only 1%) Albert Einstein publishes his paper on the photoelectric effect in 1905 for which he later receives the nobel prize. Energy efficient silicon solar cell finally built in 1941 by Russell Ohl. In the USA, Daryl Chapin, Calvin Fuller and Gerald Pearson develop the silicon photovolatic(PV) cell at Bell Labs in 1954. It was the first solar cell capable of converting enough of the sun’s into power to run everyday electrical equipments.
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Solar Cells Research Prospects Organic Solar Cells Reference History of Solar Cell
Started with French scientist Edmond Becquerel’s photoelectric experiments in 1839. First solar cell using junctions was built by an American, Charles Fritts in 1883. (It was formed using coated selenium and gold, as a result, efficiency of only 1%) Albert Einstein publishes his paper on the photoelectric effect in 1905 for which he later receives the nobel prize. Energy efficient silicon solar cell finally built in 1941 by Russell Ohl. In the USA, Daryl Chapin, Calvin Fuller and Gerald Pearson develop the silicon photovolatic(PV) cell at Bell Labs in 1954. It was the first solar cell capable of converting enough of the sun’s into power to run everyday electrical equipments.
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Solar Cells Research Prospects Organic Solar Cells Reference History of Solar Cell
Started with French scientist Edmond Becquerel’s photoelectric experiments in 1839. First solar cell using junctions was built by an American, Charles Fritts in 1883. (It was formed using coated selenium and gold, as a result, efficiency of only 1%) Albert Einstein publishes his paper on the photoelectric effect in 1905 for which he later receives the nobel prize. Energy efficient silicon solar cell finally built in 1941 by Russell Ohl. In the USA, Daryl Chapin, Calvin Fuller and Gerald Pearson develop the silicon photovolatic(PV) cell at Bell Labs in 1954. It was the first solar cell capable of converting enough of the sun’s into power to run everyday electrical equipments.
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Solar Cells Research Prospects Organic Solar Cells Reference History of Solar Cell
Started with French scientist Edmond Becquerel’s photoelectric experiments in 1839. First solar cell using junctions was built by an American, Charles Fritts in 1883. (It was formed using coated selenium and gold, as a result, efficiency of only 1%) Albert Einstein publishes his paper on the photoelectric effect in 1905 for which he later receives the nobel prize. Energy efficient silicon solar cell finally built in 1941 by Russell Ohl. In the USA, Daryl Chapin, Calvin Fuller and Gerald Pearson develop the silicon photovolatic(PV) cell at Bell Labs in 1954. It was the first solar cell capable of converting enough of the sun’s into power to run everyday electrical equipments.
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Solar Cells Research Prospects Organic Solar Cells Reference History of Solar Cell
Started with French scientist Edmond Becquerel’s photoelectric experiments in 1839. First solar cell using junctions was built by an American, Charles Fritts in 1883. (It was formed using coated selenium and gold, as a result, efficiency of only 1%) Albert Einstein publishes his paper on the photoelectric effect in 1905 for which he later receives the nobel prize. Energy efficient silicon solar cell finally built in 1941 by Russell Ohl. In the USA, Daryl Chapin, Calvin Fuller and Gerald Pearson develop the silicon photovolatic(PV) cell at Bell Labs in 1954. It was the first solar cell capable of converting enough of the sun’s into power to run everyday electrical equipments.
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Solar Cells Research Prospects Organic Solar Cells Reference Schematics of p-n junction Solar Cell
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Solar Cells Research Prospects Organic Solar Cells Reference Operation of p-n junction Solar Cell
The I-V characteristic of such a device is given by
“ qV /kT ” I = Is e − 1 − IL (1)
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Solar Cells Research Prospects Organic Solar Cells Reference Operation of p-n junction Solar Cell
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Solar Cells Research Prospects Organic Solar Cells Reference Equations related to Solar Cell
From equation (1), when I = 0, we obtain the open circuit voltage, VOC „ « „ « kT IL ∼ kT IL VOC = ln + 1 = ln (2) q IS q IS
The maximum output power Pm is, » „ « – kT qVm kT Pm = ImVm =∼ I V − ln 1 + − (3) L OC q kT q
Fill factor FF is given by, I V FF = m m (4) ILVOC And, the power conversion efficiency η
FF.I V η = L OC (5) Pin
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Solar Cells Research Prospects Organic Solar Cells Reference Why Organic Solar Cells ?
The discovery of metal-like electrical conductivity of polyacetylene in 1976 by Shirakawa with Heeger and MacDiarmid opened the field of research of polymers.
Avdantages of organic solar cells !
Relatively cheap in production and purification. Materials can be tailored for the demand. Can be used on flexible substrate. Can be shaped or tinted to suit architectural applications.
Disadvantages of solar cells!
Do not reach the energy conversion efficiency exceeding 24 % in inorganic materials. Limited lifetime/ stability issue.
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Solar Cells Research Prospects Organic Solar Cells Reference Why Organic Solar Cells ?
The discovery of metal-like electrical conductivity of polyacetylene in 1976 by Shirakawa with Heeger and MacDiarmid opened the field of research of polymers.
Avdantages of organic solar cells !
Relatively cheap in production and purification. Materials can be tailored for the demand. Can be used on flexible substrate. Can be shaped or tinted to suit architectural applications.
Disadvantages of solar cells!
Do not reach the energy conversion efficiency exceeding 24 % in inorganic materials. Limited lifetime/ stability issue.
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Solar Cells Research Prospects Organic Solar Cells Reference Why Organic Solar Cells ?
The discovery of metal-like electrical conductivity of polyacetylene in 1976 by Shirakawa with Heeger and MacDiarmid opened the field of research of polymers.
Avdantages of organic solar cells !
Relatively cheap in production and purification. Materials can be tailored for the demand. Can be used on flexible substrate. Can be shaped or tinted to suit architectural applications.
Disadvantages of solar cells!
Do not reach the energy conversion efficiency exceeding 24 % in inorganic materials. Limited lifetime/ stability issue.
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Solar Cells Research Prospects Organic Solar Cells Reference Why Organic Solar Cells ?
The discovery of metal-like electrical conductivity of polyacetylene in 1976 by Shirakawa with Heeger and MacDiarmid opened the field of research of polymers.
Avdantages of organic solar cells !
Relatively cheap in production and purification. Materials can be tailored for the demand. Can be used on flexible substrate. Can be shaped or tinted to suit architectural applications.
Disadvantages of solar cells!
Do not reach the energy conversion efficiency exceeding 24 % in inorganic materials. Limited lifetime/ stability issue.
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Solar Cells Research Prospects Organic Solar Cells Reference Why Organic Solar Cells ?
The discovery of metal-like electrical conductivity of polyacetylene in 1976 by Shirakawa with Heeger and MacDiarmid opened the field of research of polymers.
Avdantages of organic solar cells !
Relatively cheap in production and purification. Materials can be tailored for the demand. Can be used on flexible substrate. Can be shaped or tinted to suit architectural applications.
Disadvantages of solar cells!
Do not reach the energy conversion efficiency exceeding 24 % in inorganic materials. Limited lifetime/ stability issue.
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Solar Cells Research Prospects Organic Solar Cells Reference Why Organic Solar Cells ?
The discovery of metal-like electrical conductivity of polyacetylene in 1976 by Shirakawa with Heeger and MacDiarmid opened the field of research of polymers.
Avdantages of organic solar cells !
Relatively cheap in production and purification. Materials can be tailored for the demand. Can be used on flexible substrate. Can be shaped or tinted to suit architectural applications.
Disadvantages of solar cells!
Do not reach the energy conversion efficiency exceeding 24 % in inorganic materials. Limited lifetime/ stability issue.
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Solar Cells Research Prospects Organic Solar Cells Reference Why Organic Solar Cells ?
The discovery of metal-like electrical conductivity of polyacetylene in 1976 by Shirakawa with Heeger and MacDiarmid opened the field of research of polymers.
Avdantages of organic solar cells !
Relatively cheap in production and purification. Materials can be tailored for the demand. Can be used on flexible substrate. Can be shaped or tinted to suit architectural applications.
Disadvantages of solar cells!
Do not reach the energy conversion efficiency exceeding 24 % in inorganic materials. Limited lifetime/ stability issue.
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Solar Cells Research Prospects Organic Solar Cells Reference Why Organic Solar Cells ?
The discovery of metal-like electrical conductivity of polyacetylene in 1976 by Shirakawa with Heeger and MacDiarmid opened the field of research of polymers.
Avdantages of organic solar cells !
Relatively cheap in production and purification. Materials can be tailored for the demand. Can be used on flexible substrate. Can be shaped or tinted to suit architectural applications.
Disadvantages of solar cells!
Do not reach the energy conversion efficiency exceeding 24 % in inorganic materials. Limited lifetime/ stability issue.
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Solar Cells Research Prospects Organic Solar Cells Reference Why Organic Solar Cells ?
The discovery of metal-like electrical conductivity of polyacetylene in 1976 by Shirakawa with Heeger and MacDiarmid opened the field of research of polymers.
Avdantages of organic solar cells !
Relatively cheap in production and purification. Materials can be tailored for the demand. Can be used on flexible substrate. Can be shaped or tinted to suit architectural applications.
Disadvantages of solar cells!
Do not reach the energy conversion efficiency exceeding 24 % in inorganic materials. Limited lifetime/ stability issue.
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Structure Research Prospects Working principle Reference Types of organic solar cells
There are 3 types of organic solar cells.
1 Dye sentisized nanocrystalline TiO2 solar cells. 2 Molecular organic solar cells. 3 Polymer solar cells.[Meissner, 1999] Attracting great interest as photovolatic materials. Breakthrough came with the introduction of the bulk heterojunction.
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Structure Research Prospects Working principle Reference Types of organic solar cells
There are 3 types of organic solar cells.
1 Dye sentisized nanocrystalline TiO2 solar cells. 2 Molecular organic solar cells. 3 Polymer solar cells.[Meissner, 1999] Attracting great interest as photovolatic materials. Breakthrough came with the introduction of the bulk heterojunction.
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Structure Research Prospects Working principle Reference Types of organic solar cells
There are 3 types of organic solar cells.
1 Dye sentisized nanocrystalline TiO2 solar cells. 2 Molecular organic solar cells. 3 Polymer solar cells.[Meissner, 1999] Attracting great interest as photovolatic materials. Breakthrough came with the introduction of the bulk heterojunction.
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Structure Research Prospects Working principle Reference Types of organic solar cells
There are 3 types of organic solar cells.
1 Dye sentisized nanocrystalline TiO2 solar cells. 2 Molecular organic solar cells. 3 Polymer solar cells.[Meissner, 1999] Attracting great interest as photovolatic materials. Breakthrough came with the introduction of the bulk heterojunction.
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Structure Research Prospects Working principle Reference Device structure
ITO Indium Tin Oxide PEDOT:PSS Poly (ethylene-dioxythiophene) doped with polystyrenesulphonic acid MMDO-PPV (poly-(2-methyloxy, 5-(3,7 - dimethyloctyloxy)) para phenylene-vinylene) PCBM ([6,6]-Phenyl C61 butyric acid methyl ester
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Structure Research Prospects Working principle Reference Materials used
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Structure Research Prospects Working principle Reference From light into electricity
In three essential steps, light energy is transformed into electricity by organic solar cells. 1 Absorption of light 2 Charge carrier generation 3 Transport of the opposite charges to the opposite contacts.
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Structure Research Prospects Working principle Reference From light into electricity
In three essential steps, light energy is transformed into electricity by organic solar cells. 1 Absorption of light 2 Charge carrier generation 3 Transport of the opposite charges to the opposite contacts.
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Structure Research Prospects Working principle Reference From light into electricity
In three essential steps, light energy is transformed into electricity by organic solar cells. 1 Absorption of light 2 Charge carrier generation 3 Transport of the opposite charges to the opposite contacts.
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Structure Research Prospects Working principle Reference From light into electricity
In three essential steps, light energy is transformed into electricity by organic solar cells. 1 Absorption of light 2 Charge carrier generation 3 Transport of the opposite charges to the opposite contacts.
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Structure Research Prospects Working principle Reference Metal-insulator-metal(MIM) model
For four situations, a semiconductor, sandwiched between two metal electrodes with different work functions, is depicted above.
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Comparison Research Prospects Improving efficiency Reference Performance evaluation
Type of cell Efficiency(%) Research needs Crystalline silicon 24 Higher production yields, lowering of cost and energy content Multicystalline silicon 18 Lower manufacturing cost and complexity Amorphous silicon 13 Lower production costs, increase production volume and stability Organic solar cells 2-3 Improve stability and efficiency
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Comparison Research Prospects Improving efficiency Reference Outlook & Strategies
Device performance can be optimized by optimization of the device physics. Optimize the choice of metallic electrodes. Optimize the choice of donor-acceptor pair. The bandgap of the semiconductor should be chosen for efficient harvesting of the solar spectrum. Optimize the network morphology of the phase-separated composite material for enhanced transport and carrier generation.
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Comparison Research Prospects Improving efficiency Reference Outlook & Strategies
Device performance can be optimized by optimization of the device physics. Optimize the choice of metallic electrodes. Optimize the choice of donor-acceptor pair. The bandgap of the semiconductor should be chosen for efficient harvesting of the solar spectrum. Optimize the network morphology of the phase-separated composite material for enhanced transport and carrier generation.
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Comparison Research Prospects Improving efficiency Reference Outlook & Strategies
Device performance can be optimized by optimization of the device physics. Optimize the choice of metallic electrodes. Optimize the choice of donor-acceptor pair. The bandgap of the semiconductor should be chosen for efficient harvesting of the solar spectrum. Optimize the network morphology of the phase-separated composite material for enhanced transport and carrier generation.
Rahul Dewan Organic Solar Cells Introduction Physics of Organic Solar Cells Research Prospects Reference For Further Reading
M. Gratzel¨ Photoelectrochemical cells. Nature, Vol 414, 15 November 2001. C.J. Brabec et al. Plastic Solar Cells. Advanced Functional Materials, 2001, 11, No 1. February C. Winder Sentisization of Low Bandgap Polymer Bulk Heterojunction Solar Cells. S.M. Sze Semiconductor Devices, Physics and Technology. S. Dimitrijev Understanding Semiconductor Devices. D. Meissner. Photon 2, 34-37
Rahul Dewan Organic Solar Cells