While organic solar cells have been promising an inexpensive way to exploit solar. Inverted organic solar cells with n doped graphene electrodes using zinc oxide nanoparticles seungon jung, junghyun lee, jihyung seo, ungsoo kim, yunseong choi, and hyesung park department of energy engineering, school of energy and chemical engineering, low. Silicon doped graphene for improved performance of heterojunction solar cell applications shengjiao zhang,a xiaoqiang li,a peng wang,a zhiqian wu,a huikai zhong,a wenli xu,a zhijuan xua and shisheng lina a college of information science and electronic engineering, zhejiang university. Due to the increased optical absorption, organic solar cells with fourlayer graphene with the same sheet resistance as ito at 30. They are an important component in a number of electronic devices including liquidcrystal displays, oleds, touchscreens and photovoltaics. Graphene additionally is a material with a very high tensile strength so it can be successfully used on the silicon, flexible and organic substrates as well. How graphene is taking solar cells to the next level youtube. In general, tcos for use as thinfilm electrodes in solar cells should have a minimum carrier concentration on the order of 10 20 cm. Various studies have reported opv devices with graphene electrodes showing comparable performances to itobased opv cells. Jv characteristics of a semitransparent organic solar cell with graphene top electrode measured under solar simulator am 1. Now, as a step along the way to using graphene as a transparent electrode in opvs, researchers have capped a thin layer of ito with graphene and used it as an electrode in an organic solar cell. However, the electrical conductivity of graphene films synthesized by chemical vapor deposition cvd is still inferior to that of conventional indium tin oxide ito electrodes of comparable transparency, resulting in a lower performance of oscs. Small molecular weight organic solar cells can be directly deposited. Article extremely stable graphene electrodes doped with macromolecular acid sungjoo kwon1, taehee han2,3, taeg yeoung ko4, nannan li 5, youngsoo kim6, dong jin kim6,7, sanghoon bae3, yang yang3, byung hee hong 7, kwang s.
Pss layer and a donoracceptor blend layer commonly containing p 3 ht or fullerenes or both. An analysis of how to use graphene as an electrode for such solar cells was published on dec. Flexible organic solar cells over 15% efficiency with polyimideintegrated graphene electrodes author links open overlay panel donghwan koo 1 sungwoo jung 1 jihyung seo 1 gyujeong jeong 1 yunseong choi 1 junghyun lee 1 sang myeon lee 1 yongjoon cho 1 mingyu jeong 1 jungho lee 1 jiyeon oh 1 changduk yang 1 hyesung park 1 2. Jan 06, 2011 graphene electrodes would match flexibility, transparency and low cost needed for organic solar cells. Silicon doped graphene for improved performance of heterojunction solar cell applications shengjiao zhang,a shisheng lin,a xiaoqiang li,a xiaoyi liu,b hengan wu,b peng wang,a zhiqian wu,a huikai zhong,a wenli xua and zhijuan xua a college of information science. Conclusions and outlook u author information v corresponding author v notes v biographies v acknowledgments v abbreviations v references w 1. Nitrogen doped graphene nanoribbons for organic photovoltaic.
Published 23 november 2010 iop publishing ltd nanotechnology, volume 21, number 50. Aside from the two electrodes, traditional organic solar cells contain an active pedot. In 2012, researchers from the university of florida reported a record efficiency of 8. The devices also show good air stability, indicating that multilayer graphene is a promising environmental barrier. The potential of graphene as an ito replacement in organic. Graphene as a material for solar cells applications in. In addition, it is flexible, like the organic solar cells themselves, so it could be part of installations that require the panel to follow the contours of a structure, such as a patterned roof. Graphene electrodes for organic solar cells mit news. Department of chemistry, school of science, the university of tokyo, 731 hongo. In fact, it means that solar cells based on graphene can significantly expand the absorbed spectrum wavelengths of electromagnetic radiation.
Over 14% efficiency foldingflexible itofree organic solar cells enabled by ecofriendly acidprocessed electrodes author links open overlay panel wei song 1 2 ruixiang peng 1 2 like huang 1 chang liu 1 billy fanady 1 tao lei 1 2 ling hong 1 2 jinfeng ge 1 antonio facchetti 3 ziyi ge 1 2 4. A transparent conductive electrode tce is an essential component of various optoelectronic devices such as solar cells, liquidcrystal displays lcd, lightemitting diodes led, and touch screens. In this work graphene sheets grown by chemical vapor deposition cvd with controlled numbers of layers were used as transparent electrodes in organic photovoltaic opv devices. In addition, a graphene electrode can be just 1 nanometer thick a fraction as thick as an ito electrode and a far better match for the thin organic solar cell itself. Pss, which is sandwiched between silicon wafer and graphene electrode. This layer is the building block of graphite and carbon nanotubes and it has been studied widely by theorists since the middle of the last century. Large area graphene films were produced by chemical vapor deposition on copper foils and transferred onto glass as transparent electrodes. However, the electrical conductivity of graphene films synthesized by chemical vapor deposition cvd is still inferior to that of conventional indium tin oxide ito electrodes of comparable transparency. Its high transparency, conductivity, flexibility, and abundance make it an excellent material to be applied in the field of organic. Graphene based electrode materials for solar cell and. Starting from few percentage points in 2000, they have. Direct and dry deposited singlewalled carbon nanotube films doped with moox as electronblocking transparent electrodes for flexible organic solar cells. Free flexible organic solar cells with graphene top. Jan 06, 2011 graphene is transparent, so that electrodes made from it can be applied to the transparent organic solar cells without blocking any of the incoming light.
P and n doped graphene electrodes have been used and the solar cells achieved a maximum efficiency of 1. Jun 15, 2017 imagine a future in which solar cells are all around uson windows and walls, cell phones, laptops, and more. Studies have shown that doped graphene can change one absorbed photon of a few electrons, which in practice means an increase in efficiency of solar panels. Doped graphene electrodes for organic solar cells iopscience. Doped and textured graphene as electrode for organic solar. Doped graphene electrodes for organic solar cells hyesung park 1, jill a rowehl2,kikangkim1, vladimir bulovic and jing kong1 1 department of electrical engineering and computer sciences, massachusetts institute of technology, cambridge, ma 029, usa 2 department of materials science and engineering, massachusetts institute of technology. Supporting information the application of highly doped single. This section also discusses graphene undopeddoped as a chargetransport layertransparent electrode for organicperovskite solar cells. Chargetransfer doping of graphene with smallmolecule dopants such as inorganic smallmolecule acids e. Graphene for electrodes in organic solar cells could. Graphene for electrodes in organic solar cells could reduce costs. A promising approach for making solar cells that are inexpensive, lightweight and flexible is to use organic that is, carboncontaining compounds instead of expensive, highly purified silicon. This means that if their new electrode is successfully implemented, we could see solar cells linked with superconductors that have 3,000 percent more storage capacity than whats currently possible. In a solar cell, the electric field formed due to the potential energy barrier between two dissimilar materials at the interface is capable of separating the electrons and holes generated by absorption of.
Transparent, flexible solar cells combine organic materials. N doped graphene nanoplatelets as superior metalfree counter electrodes for organic dyesensitized solar cells. Mar 12, 2014 graphene has been employed as transparent electrodes in organic solar cells oscs because of its good physical and optical properties. Doped and textured graphene as electrode for organic solar cells. Doped graphene electrodes for organic solar cells article pdf available in nanotechnology 2150. Organic solar cell abstract phgraphene gra composite. Inverted organic solar cells with ndoped graphene electrodes using zinc oxide nanoparticles seungon jung, junghyun lee, jihyung seo, ungsoo kim, yunseong choi, and hyesung park department of energy engineering, school of energy and chemical engineering, low. The device combines lowcost organic carboncontaining materials with electrodes of graphene, a flexible, transparent material made from inexpensive, abundant carbon sources. Silicon doped graphene for improved performance of. Metalelectrodefree windowlike organic solar cells with pdoped carbon nanotube thinfilm electrodes il jeon1, clement delacou2, antti kaskela3, esko i. In organic solar cells, graphene materials have been used as electron acceptors238 and hole conductors.
Pdf in this work graphene sheets grown by chemical vapor deposition cvd with controlled numbers of layers were used as transparent electrodes in. Graphenebased transparent conductive electrodes sigma. Visiblytransparent organic solar cells on flexible substrates with all graphene electrodes, advanced energy materials 2016. Graphene applications in other types of solar cells u 7.
Development of annealingfree, solutionprocessable inverted. Highly efficient counter electrodes ces for dyesensitized solar cells dsscs were developed using thin films of scalable and highquality, nitrogen doped graphene nanoplatelets ngnp, which was synthesized by a simple twostep reaction sequence. Two key problems have slowed the wholesale adoption of graphene electrodes. Graphene, a material composed of oneatomthick planar sheets of sp 2 bonded carbon atoms with a twodimensional honeycomb structure, has been proposed for many applications due to its remarkable electronic, optical, thermal, and mechanical properties. Keywords ball milling, dyesensitized solar cells, lowcost counter electrodes, natural sensitizer, tellurium doped graphene 1 introduction according to the latest statistics by the renewable. Graphene is transparent, so that electrodes made from it can be applied to the transparent organic solar cells without blocking any of the incoming light. Although znoa ntype oxide semiconductorcan lead to ntype doping of the graphene film, direct coating of zno on graphene is found to have a destructive effect and therefore yields a high sheet. Pdf doped graphene electrodes for organic solar cells. Graphene has been proposed as a promising transparent conducting electrode material in organic photovoltaic opv solar cells to substitute the widely used indium tin oxide ito. Can graphene outperform indium tin oxide as transparent. This new graphenebased electrode could boost solar. Graphene electrodes could replace indium tin oxide for lower. Capacityboosted supercapacitors would offer both longterm reliability and quickburst energy release, he says.
It was found that for devices with pristine graphene electrodes, the power conversion efficiency pce is comparable to their counterparts with indium tin oxide ito electrodes. Metalelectrodefree windowlike organic solar cells with. P and n doped graphene electrodes have been used and the solar cells. Visiblytransparent organic solar cells on flexible substrates with allgraphene electrodes, advanced energy materials 2016. Many technical advances have made solar cells quite efficient and affordable in recent years. Introduction dyesensitized solar cells dsscs have taken up broad interest as a promising lowcost solar cell. Nitrogendoped grapheneplatinum counter electrodes for dye. The resultant ngnp was deposited on fluorine doped sno2 ftoglass substrates by using electrospray espray coating, and their. May 23, 2018 chargetransfer doping of graphene with smallmolecule dopants such as inorganic smallmolecule acids e. Graphene is not only being used as a transparent and flexible electrode but also as the pv material. Figure 5 a presents a schematic view of semitransparent organic solar cells with allgraphene electrodes comprising twolayer stacked graphene. Over 14% efficiency foldingflexible itofree organic. While indium tin oxide ito is the most widely used, alternatives include widerspectrum transparent conductive oxides tcos, conductive.
Kauppinen3, shigeo maruyama2,4, and yutaka matsuo1, 1. Nitrogen doped graphene nanoribbons for organic photovoltaic applications by donatela elsa bellone a report submitted in partial satisfaction of the requirements for the degree of master of science in electrical engineering and computer science in the graduate division of the university of california, berkeley committee in charge. The doping with nitrogen leads to a power conversion efficiency of 7. Graphenebased transparent electrodes for hybrid solar cells. Replacing indiumtinoxide as the material for electrodes in organic solar cells provides a number of benefits. Jul 17, 2017 aside from the two electrodes, traditional organic solar cells comprise of an active pedot.
Graphene layer could allow solar cells to generate power when. We demonstrate that solutionprocessed graphene thin films can serve as transparent conductive anodes for organic photovoltaic cells. Semitransparent flexible organic solar cells employing doped. The graphene electrodes were deposited on quartz substrates by spin coating of an aqueous dispersion of functionalized graphene, followed by a reduction process to reduce the sheet resistance. In this video we look at how the miracle material graphene is helping to improve solar cells.
Highly efficient counter electrodes ces for dyesensitized solar cells dsscs were developed using thin films of scalable and highquality, nitrogendoped graphene nanoplatelets ngnp, which was synthesized by a simple twostep reaction sequence. Organic solar cells oscs have received a lot of attention from both academia and industry in the. Hyesung park 1, jill a rowehl 2, ki kang kim 1, vladimir bulovic 1 and jing kong 1. Aside from the two electrodes, traditional organic solar cells comprise of an active pedot. Over 14% efficiency foldingflexible itofree organic solar.
This paper thus strongly support the use of graphene in solar cells and looking forward towards cheap, highly efficient graphene solar cells. Organic semiconductor solar cells are a promising route to scalable, economically. Organic solar cells with solutionprocessed graphene. The hybrid solar cell devices consist of solutionprocessed poly 3,4ethlenedioxythiophene.
The efficiency of organic solar cells with graphene elec. The wrinkled phgra composite electrode exhibits excellent transmittance of 88. However, integration of graphene into the opv fabrication process is still in development. Department of chemistry, school of science, the university of tokyo, 731 hongo, bunkyoku, tokyo 1033, japan. Nitrogendoped graphene ngr was utilized in dyesensitized solar cells for energy harvesting. At elevated temperatures, pet film may thermally expand owing to its lower t g of 70c80c, which can structurally deform the overlying graphene layer and thus degrade the electrical properties of the graphene electrode. The solar cells based on graphene electrodes, especially those doped with hno 3, have comparable performance. Pss layer has been replaced by graphene derivatives and are generally used as holetransport layers in organic solar cells.
Jul 28, 2017 in addition, a graphene electrode can be just 1 nanometer thick a fraction as thick as an ito electrode and a far better match for the thin organic solar cell itself. Graphene solar cell imperial international journal. Pss layer and a donoracceptor blend layer commonly composed of p3ht or fullerenes or both. Organic semiconductor solar cells oscs have recently experienced an impressive improvement in power conversion ef. The application of highly doped singlelayer graphene.
Chemical doping and enhanced solar energy conversion of. Transparent conducting films tcfs are thin films of optically transparent and electrically conductive material. The resultant ngnp was deposited on fluorinedoped sno2 ftoglass substrates by using electrospray espray coating, and their. Once the pigraphene single or multilayercu foil stack was obtained, cu etching and graphene doping were conducted simultaneously using an aqueous ammonium persulfate aps and imidazole solution, which enabled production of graphene films with high conductivity suitable for application in transparent electrodes in oscs.
Ndoped graphene nanoplatelets as superior metalfree counter. Metalelectrodefree windowlike organic solar cells with p. Metalelectrodefree windowlike organic solar cells with p doped carbon nanotube thinfilm electrodes il jeon1, clement delacou2, antti kaskela3, esko i. Imagine a future in which solar cells are all around uson windows and walls, cell phones, laptops, and more. Furthermore, the doping both improves the conductivity and shifts the work function of the graphene electrode, resulting in improved overall pce. A new flexible, transparent solar cell developed at mit brings that future one step closer. Graphene and carbonnanotubebased transparent electrodes. Ndoped graphene nanoplatelets as superior metalfree. Light absorbance spectra of semitransparent solar cells with different thicknesses of p3ht. The resulting materials were applied as the transparent electrodes of solar cells, the freestanding electrodes with enhanced mechanical strength, and the cathodes of fuel cells for oxygen reduction. Consequently, graphene seems to be a suitable candidate as a conductive electrode in devices such as organic lightemitting diode 187, solar cells 188 189190, and an electronic device.
The graphenebased transparent and conductive films were demonstrated to be costeffective electrodes working in organicinorganic hybrid schottky solar cells. Dsscs based on specific nanoplatelets designated ngnp5 display superior photovoltaic performance power. Organic solar cells using cvdgrown graphene electrodes. Apr 16, 2017 this means that if their new electrode is successfully implemented, we could see solar cells linked with superconductors that have 3,000 percent more storage capacity than whats currently possible. Pss layer has been replaced by graphene derivatives and are commonly used as holetransport layers in organic solar cells. Flexible organic solar cells over 15% efficiency with. However, pristine graphene has high sheet resistance r sh 300. The first problem is depositing the graphene electrodes onto the solar cell. Graphene oxide nanocomposites for potential wearable solar. In addition, graphene has a low coefficient of light absorption 2. Graphene and other 2d materials for advanced solar cells. In order to verify the generality of our method, we have also tested organic inorganic hybrid solar cells 49,50,51 and quantumdot based solar cells 52,53, all using graphene electrodes and the.
Organic semiconductor solar cells are a promising route to scalable, economically viable, energy conversion technologies due to the potential for development of lowcost, flexible, largearea cells and modules. This new graphenebased electrode could boost solar storage. Aadepartment of electrical engineering and computer sciences, massachusetts institute of technology, cambridge, ma 029, usa, abdepartment of materials science and engineering, massachusetts institute of technology, cambridge, ma 029. The devices also show good air stability, indicating that multilayer graphene is a promising environmental barrier that can protect the organic solar cells from air. Graphene layer could allow solar cells to generate power. Allcarbon electrodes for flexible solar cells mdpi. Bulovickong create graphene electrodes for organic solar. Novel technique using graphene to create solar cells. Graphene films were also used as conductive and transparent electrodes to replace ito in organic 14. Ultrathin organic solar cells with graphene doped by.
Red high surface area graphene material structures. Keywords ball milling, dyesensitized solar cells, lowcost counter electrodes, natural sensitizer, telluriumdoped graphene 1 introduction according to the latest statistics by the renewable. Graphene materials and their use in dyesensitized solar cells. Graphene has been employed as transparent electrodes in organic solar cells oscs because of its good physical and optical properties. A big disadvantage remains in the fact that solar cells produce no power. Graphene nanoplatelets doped with n at its edges as metal. Graphene electrodes for organic solar cells researchers identify technique that could make a new kind of solar photovoltaic panel practical nanotechnology, hyesung park et al 2010 nanotechnology 21 505204.