Shockleyqueisser limit, including solar cells exploiting multipleexciton generation, hotcarrier collection, upconversion, downconversion and intermediateband photovoltaics5,6. Intermediate band solar cells based on inas quantum dots. We have studied the photocurrent generated by strain balanced quantum posts embedded in a gaas single crystal, and compared our results with quantum dot based devices. Performance analysis of quantum dot intermediate band solar cell qd ibsc. Understanding intermediateband solar cells antonio luque, antonio marti and colin stanley the intermediateband solar cell is designed to provide a large photogenerated current while maintaining a high output voltage. Hubbard1,b 1nanopower research laboratories, rochester institute of technology, rochester, new york 14623, usa. Many approaches have been experienced in order to enhance the solar cell efficiency like tandem cells, quantum well cells etc.
Intermediate band quantum dot solar cells mowafak aljassim, andrew norman and mark hanna national renewable energy laboratory, golden, colorado 80401 currently there is a drive to investigate a new generation of improved efficiency photovoltaic pv. Model for intermediate band solar cells incorporating carrier. These too are exciting scientific developments that have potential to eventually result in high. Two terminal and four terminal tandem intermediate band solar cells27 figure 7. The intermediate band solar cell ibsc is one such possibility, where an intermediate energy band ib is placed in the otherwise forbidden. The intermediate band solar cell is a theoretical concept with the potential for exceeding the performance of conventional singlegap solar cells. The intermediate band solar cell ibsc is one of the candidate concepts. Theoretically, introducing an ib allows two photons with energy less than the bandgap to excite an electron from the valence band to the conduction band. The intermediate band solar cell ibsc is a novel photovoltaic device with the potential of surpassing the efficiency limit of conventional solar cells. To make this possible, these cells incorporate an energy band that is partially filled with electrons within the forbidden bandgap. The limiting efficiency of an intermediate band ib solar cell under the terrestrial am1. If a base material without intermediate band is added to the two section lowhigh state filling devices, the efficiency is further increased to 61. The intermediate band solar cell ibsc is one such possibility, where an intermediate energy band ib. They are based in a material that, in addition to the conventional conduction and valence bands, has an electronic band named intermediate band located inside the bandgap and separated from the conduction and valence band by a null density of states.
Furthermore, if the quasi fermi level qfl of the electrons in the. Resolving spectral overlap issue of intermediate band solar. It introduces an intermediate band ib energy level in between the valence and conduction bands. Model for intermediate band solar cells incorporating. Intermediate band ib solar cells is a relatively new solar cell concept, that have efficiency limits that are 50% higher than for conventional solar cells, but so far very attempts have been made to realize the concept. This intermediate band absorbs photons that would otherwise be lost to heat or some other form of dissipated energy and then converts them into electrical energy dhomkar, 20. Resolving spectral overlap issue of intermediate band solar cells using nonuniform subbandgap state. Increasing the current while preserving the voltage 2 7. An ibsc is composed of an ib material sandwiched between two ordinary n and p type semiconductors, which act as selective contacts to the conduction band cb and valence band vb, respectively. One novel design which has shown promise for ingan is the intermediate band solar cell, offering a maximum theoretical efficiency of 63% 3. The intermediate band ib solar cell has been proposed to increase the current of solar cells while at the same time preserving the output voltage in order to. In ib materials there is an additional intermediate energy band in the band gap of the semiconductor. Starting with the impurity photovoltaic solar cell in 1960, where sequential absorption was suggested to proceed via defect levels,1 the concept.
Understanding intermediateband solar cells nature photonics. Intermediate band ib solar cells aim to exploit in solar cells the energy of below bandgap energy photons. Present status of intermediate band solar cell research. Development of intermediate band solar cell through ingan. In this way the photocurrent may be enhanced by pumping electrons from the valence band vb to the conduction band cb by means of two subbandgap photons in successive events.
Multiple stacked ingangan quantum dots are embedded into an ingan p. Intermediate band solar cells ibsc have recently attracted renewed interest as a potential approach to achieve high power conversion efficiency pce. Intermediate band solar cell ibsc 2, 3, where energy levels are introduced within a semiconductor bandgap, to allow the sequential absorption of. The results show four energy gap combinations giving similar limiting efficiencies. The incorporation of phosphorous in the matrix to partially compensate the accumulated stress enables a significant increase of the. To make this possible, these cells incorporate an energy band that is partially filled with electrons within the forbidden bandgap of a semiconductor. This novel photovoltaic converter bases its superior theoretical efficiency over singlegap solar cells by enhancing its photogenerated current, via the twostep absorption of sub band gap photons. The intermediateband solar cell ibsc is one of the most promising candidates for the next generation of photovoltaic devices, with a detailed balance efficiency of 63. This novel photovoltaic converter bases its superior theoretical efficiency over singlegap solar cells by enhancing its photogenerated current, via the twostep absorption of subband gap photons. Some advantages of intermediate band solar cells based on type ii quantum dots antonio luque,1,2,a pablo g. Photonic design principles for ultrahighefficiency. The intermediate band solar cell ibsc is a new concept proposed to better match the solar spectrum by absorbing subbandgap energy photons. After discussing some basics from electrodynamics in chapter 4 and solar radiation in chapter 5, we spend several. Jan 31, 2011 for intermediate band solar cells, quantum dots are used to create the intermediate bands from the con fined electron states in the conduction band.
The intermediateband solar cell is designed to provide a large photogenerated current while maintaining a high output voltage. Photons with insufficient energy to pump electrons from the valence band to the conduction band can use this. Rochester institute of technology nasa inasgaasgap inasganas university of tokyo univesity of tsukuba r. Intermediate band ib solar cells ideally contain a level or band within the semiconductor bandgap. Intermediate band ib photovoltaics have the potential to be highly efficient and cost effective solar cells. Solving the energy crisis with intermediate band solar cells. An electronic ratchet is required in nanostructured intermediate. Intermediate band solar cells to capture and use photons less than the bandgap energy, ib solar cells can be used that are based on the so called in termediate band ma te rals. Intermediate band solar cells 0 e i eg ec iv cv ci vb ib cb qv intermediate band solar cells can be very efficient max. Lin1, szeming fu1, yankai zhong2 1 institute of electronic engineering, national chiaotung university, hsinchu, taiwan 30010 2 department of electrophysics, national chiaotung university, hsinchu, taiwan 30010 abstract the modeling of intermediate band solar cell has. Phillips department of electrical engineering and computer science, solidstate electronics laboratory, the university of michigan, ann arbor, michigan 481092122, usa. Intermediate band solar cells solar cell materials with more than one bandgap offer the possibility to increase the efficiency of the solar cell beyond that of a single bandgap cell.
Possible intermediateband solar cell materials diluted iivi oxide semiconductors e. Intermediate band photovoltaics in solar cell research provides methods for exceeding the shockleyqueisser limit on the efficiency of a cell. Effect of electric field on carrier escape mechanisms in quantum dot intermediate band solar cells yushuai dai,1 stephen j. Understanding intermediateband solar cells article pdf available in nature photonics 63. Intermediate band quantum dot solar cell linkedin slideshare. Solar cells based on as is well known, the maximum ther. Device simulation of intermediate band solar cells. High power conversion efficiency of intermediate band. Solar cells and quantum dot technology for highefficiency photovoltaics. An ibsc is composed of an ib material sandwiched between two ordinary n and p type semiconductors, which act as selective contacts to the conduction band cb and valence band vb. To realize high efficiency solar cells, new concepts beyond the shockleyqueisser limit are widely investigated. New solar cell designs may provide a way around this problem. Intermediate band solar cells intermediate band vs multijunction solar cell max. In recent years, great progress has been made in developing materials with intermediate bands, though power conversion efficiencies have.
Recent progress on intermediateband solar cells and. Effect of electric field on carrier escape mechanisms in. A detailed discussion is given on the thermodynamics of solar energy conversion in ibscs, the device physics, and the carrier dynamics processes with a particular emphasis on the twostep intersubband absorptionrecombination processes that are of paramount importance in a successful implementation. Limiting efficiency of an intermediate band solar cell. Ibscs require light concentration not only to reduce the device cost but also to ensure optimal operation when carrier photogeneration is outperforming the. By means of the intermediate band, it is possible to absorb belowbandgap energy photons. Modeling of the intermediate band tandem solar cell using the am1. This is in contrast to the more studied case of an ib solar cell under a blackbody spectrum where a single optimum combination is found. In this paper, a model for intermediate band solar cells is built based on the generally understood physical concepts ruling semiconductor device operation, with special emphasis on the behavior at low temperature. Some advantages of intermediate band solar cells based on. Double band absorption ib solar cells an ib solar cell38 consists of an ib material situated between two conventional semiconductors, n and ptype, that play the role of selective contacts to cb and vb electrons, respectively as shown. One approach to implement this idea is to form an intermediate band ib with creating metallic intermediate band inside the host semiconductor. Influence of band formation on dynamical processes in inasgaas quantum dot arrays. Limiting efficiency of an intermediate band solar cell under.
The model is compared to j lv oc measurements at concentrations up to about suns and at temperatures down to 20 k, as well as measurements of the radiative recombination. Intermediate band solar cells can achieve this high efficiency due to the fabrication of a socalled intermediate band within the host semiconductor material. Mar 16, 20 the intermediate band ib is an electronic band located within the semiconductor band gap, separated from the conduction and the valence band by a null density of states. Semiconductor materials for intermediate band solar cells. Modeling of the intermediate band tandem solar cell. Intermediate band solar cells ibscs are photovoltaic devices. This is predicted to produce solar cells with enhanced photocurrent without voltage degradation. Review of experimental results related to the operation of intermediate band solar cells inigo ramiro, antonio marti, elisa antolin, and antonio luque abstractthe intermediate band solar cell ibsc has drawn the attention of the scientific community as a means to achieve highefficiency solar cells. Quantum dot intermediate band solar cells qdibscs 63% eg1.
Intermediate band solar cells based on inas quantum dots embedded in ingaas quantum well a thesis submitted in partial fulfillment of the requirements for the degree of master of science in electrical engineering by ramesh vasan anna university bachelor of engineering in electronics and instrumentation, 2010 may 20 university of arkansas. Intermediateband dynamics of quantum dots solar cell in. Intermediate band solar cells ibsc have been proposed as a potential design for the next generation of highly efficient photovoltaic devices. The intermediate band solar cell ibsc is a socalled third generation solar cell, based on a new type of semiconductor materials.
Research article resolving spectral overlap issue of intermediate band solar cells using nonuniform subbandgap state. The intermediate band ib is an electronic band located within the semiconductor band gap, separated from the conduction and the valence band by a null density of states. Photons with energy less than the band gap can contribute to the device output by using the intermediate bands as a ladder to the conduction band. A detailed discussion is given on the thermodynamics of solar energy conversion in ibscs, the device physics, and the carrier dynamics processes with a particular emphasis on the twostep intersubband absorptionrecombination processes that are of paramount importance in a successful. Understanding the operation of quantum dot intermediate. The intermediate band solar cell is designed to provide a large photogenerated current while maintaining a high output voltage. Review of power control mechanisms in cellular system. Abstract the intermediate band ib solar cell has been proposed to increase the current of solar cells while at the same time preserving the. Intermediate band photovoltaics based on interband. Review of experimental results related to the operation of. Understanding intermediate band solar cells antonio luque, antonio marti and colin stanley the intermediate band solar cell is designed to provide a large photogenerated current while maintaining a high output voltage. Intermediate band solar cells based on znteo by weiming wang a dissertation submitted in partial fulfillment of the requirements for the degree of doctor of philosophy electrical engineering in the university of michigan 2010 doctoral committee. Full text pdf 1129k abstracts references25 citedby5 in order to surpass the thermodynamic shockleyqueisser limit of energy conversion efficiency of singlejunction solar cells, advanced concepts using multijunction tandem structure and quantum nanostructure are presently. A unified mathematical framework for intermediate band.
Designing of 3d transistor based home appliances for low power dissipation through cost analysis. Capability for measuring up to 5000 suns at 20 k some results obtained in samples with quantum dots. Characterization of intermediate band materials and solar. Used to exploit the energy of below band gap energy photons. When the ib concept was proposed in 1997, there were no known intermediate band materials. Emitter degradation in quantum dot intermediate band solar cells. Recent progress on quantum dot intermediate band solar cells. Understanding intermediateband solar cells nasaads. Intermediate band solar cells department of physics ntnu. For intermediateband solar cells, quantum dots are used to create the intermediate bands from the con fined electron states in the conduction band. Recent progress on intermediateband solar cells and quantum. Part ii aims to cover all the physical fundamentals that are required for understanding solar cells in general and the different technologies in particular. Resolving spectral overlap issue of intermediate band. The tandem intermediate band solar cell will have six different band gaps and is hence comparable with a six singlejunction tandem cell.
Apr 30, 2008 the limiting efficiency of an intermediate band ib solar cell under the terrestrial am1. A unified mathematical framework for intermediate band solar cells albert s. Linares,2 alex mellor,2 viacheslav andreev,1 and antonio marti2 1ioffe physicotechnical institute, 26 polytekhnicheskaya, st. From the importance of device physics, we have developed a device simulator for ibscs. Intermediate band solar cell power control mechanisms. Efficiency contour plots under concentration a 1 am1. The solar cell physics group is involved in both theoretical studies of such cells and in fabrication of new materials for. Mar 07, 2014 intermediate band ib photovoltaics have the potential to be highly efficient and cost effective solar cells. Understanding the operation of quantum dot intermediate band solar cells a. Quantum nanostructures, such as quantum dots qd, arranged in superlattice sl arrays produce a miniband ib that is separated by a region of zero density of states from other states in the. New hamiltonian for a better understanding of the quantum. The intermediate band solar cell ibsc is one such possibility, where an intermediate energy band ib is placed in the otherwise forbidden bandgap of the solar. Model for intermediate band solar cells incorporating carrier transport and recombination albert s. To make this possible, these cells incorporate an energy band that.
1295 538 90 248 426 935 483 168 1326 1429 1119 148 1183 484 50 1152 696 707 118 581 81 14 500 575 649 1453 467 1121 88 165 593