المؤلفون: Laura M. Pérez, Asmae EL Aouami, Kawtar Feddi, Vittorianna Tasco, Abdellatif Ben Abdellah, Francis Dujardin, Maykel Courel, Javier A. Riquelme, David Laroze, EL Mustapha Feddi

المصدر: Crystals; Volume 12; Issue 7; Pages: 1002

مصطلحات موضوعية: intermediate band solar cells, quantum dots, power conversion efficiency

الوصف: Photovoltaic cells, based on quantum dots implementation in the intrinsic region, are one of the most widely studied concepts nowadays to obtain a high solar conversion efficiency. The challenge in this third generation of solar cells is to find a good combination of materials that allows obtaining higher efficiency with low cost. In this study, we consider a juxtaposition of two kinds of quantum dots (dot/barrier) inside the I region of the PIN junction: the first combination of semiconductors includes the two configurations, PbTe/CdTe and PbSe/ZnTe, and the second combination is InN/GaN. Thus the intermediate band can be tailored by controlling the size of the dots and the inter-dot distances. The principal interest of this investigation is to determine the optimized parameters (the dot size and the inter-dot distance), leading to obtain a better solar cell efficiency. Intermediate bands, their positions, and their widths, are determined using 3D confined particles (electron and hole). Their energy levels are determined by solving the Schrödinger equation and solving the well-known dispersion relation in the Kronig–Penney model.

وصف الملف: application/pdf

العلاقة: https://dx.doi.org/10.3390/cryst12071002Test

الإتاحة: https://doi.org/10.3390/cryst12071002Test

المؤلفون: Asmae El Aouami, Laura M. Pérez, Kawtar Feddi, Mohamed El-Yadri, Francis Dujardin, Manuel J. Suazo, David Laroze, Maykel Courel, El Mustapha Feddi

المصدر: Nanomaterials; Volume 11; Issue 5; Pages: 1317

مصطلحات موضوعية: intermediate band solar cells, quantum dots, power conversion efficiency

الوصف: Solar cells that are based on the implementation of quantum dots in the intrinsic region, so-called intermediate band solar cells (IBSCs), are among the most widely used concepts nowadays for achieving high solar conversion efficiency. The principal characteristics of such solar cells relate to their ability to absorb low energy photons to excite electrons through the intermediate band, allowing for conversion efficiency exceeding the limit of Shockley–Queisser. IBSCs are generating considerable interest in terms of performance and environmental friendliness. However, there is still a need for optimizing many parameters that are related to the solar cells, such as the size of quantum dots, their shape, the inter-dot distance, and choosing the right material. To date, most studies have only focused on studying IBSC composed of cubic shape of quantum dots. The main objective of this study is to extend the current knowledge of IBSC. Thus, we analyze the effect of the shape of the quantum dot on the electronic and photonic characteristics of indium nitride and indium gallium nitride multiple quantum dot solar cells structure considering cubic, spherical, and cylindrical quantum dot shapes. The ground state of electrons and holes energy levels in quantum dot are theoretically determined by considering the Schrödinger equation within the effective mass approximation. Thus, the inter and intra band transitions are determined for different dot sizes and different inter dot spacing. Consequently, current–voltage (J-V) characteristic and efficiencies of these devices are evaluated and compared for different shapes. Our calculations show that, under fully concentrated light, for the same volume of different quantum dots (QD) shapes and a well determined In-concentration, the maximum of the photovoltaic conversion efficiencies reaches 63.04%, 62.88%, and 62.43% for cubic, cylindrical, and spherical quantum dot shapes, respectively.

وصف الملف: application/pdf

العلاقة: Theory and Simulation of Nanostructures; https://dx.doi.org/10.3390/nano11051317Test

الإتاحة: https://doi.org/10.3390/nano11051317Test

المؤلفون: El Aouami Camelia, Louhmadi Abdeljalil

المصدر: E3S Web of Conferences, Vol 319, p 01108 (2021)

مصطلحات موضوعية: foreign direct investments, territorial offer, attractiveness of the territory, territorial economy, energy competitiveness, competitiveness of the territory, factor analysis, Environmental sciences, GE1-350

الوصف: The competitiveness of the territorial offer characteristics determines the attractiveness of FDI (foreign direct investments), the components of the territory such as the climate, natural resources, energy competitiveness, infrastructures, the business climate, and others several factors which constitute the components of the territorial offer. In through a survey conducted with investors foreigners settled in the area TTA (Tangier-Tetouan, Al Hoceima) we tried to analyze the set are features of the offer of u territory while emphasizing energy and competitiveness of the climate. Still, we have Vons tried to determine the are obstacles enrayant attractiveness for FDI. Thus, the results of our analysis can be classified into groups the variables are the offer of territory according to the choice priority of investors and therefore a diagnosis (strengths / weaknesses) of the territory. Competitiveness in energy infrastructures plays a driving role in the attractiveness of the offer; on the other hand, energy costs can constitute an obstacle to the attractiveness of the territory.

العلاقة: https://www.e3s-conferences.org/articles/e3sconf/pdf/2021/95/e3sconf_vigisan_01108.pdfTest; https://doaj.org/toc/2267-1242Test; https://doaj.org/article/f3b774cb5f7e428d8a31e63069131826Test

الإتاحة: https://doi.org/10.1051/e3sconf/202131901108Test
https://doaj.org/article/f3b774cb5f7e428d8a31e63069131826Test

المؤلفون: M.E. Mora-Ramos, A. El Aouami, E. Feddi, A. Radu, R.L. Restrepo, J.A. Vinasco, A.L. Morales, C.A. Duque

المصدر: Heliyon, Vol 6, Iss 1, Pp e03194- (2020)

مصطلحات موضوعية: Condensed Matter Physics, Nanotechnology, Quantum dot, Donor impurity, Binding energy, Optical Absorption, Science (General), Q1-390, Social sciences (General), H1-99

الوصف: The properties of the conduction band energy states of an electron interacting with a donor impurity center in spherical sector-shaped GaAs-Al0.3Ga0.7As quantum dots are theoretically investigated. The study is performed within the framework of the effective mass approximation through the numerical solution of the 3D Schrödinger equation for the envelope function via the finite element method. The modifications undergone by the spectrum due to the changes in the conical structure geometry (radius and apical angle) as well as in the position of the donor atom are discussed. With the information regarding electron states the linear optical absorption coefficient associated with transition between confined energy levels is evaluated and its features are discussed. The comparison of results obtained within the considered model with available experimental data in GaAs truncated-whisker-like quantum dots shows very good agreement. Besides, our simulation leads to identify the lowest energy photoluminescence peak as donor-related, instead of being associated to acceptor atoms, as claimed after experimental measurement (Hiruma et al. (1995) [14]). Also, a checking of our numerical approach is performed by comparing with analytical solutions to the problem of a spherical cone-shaped GaN with infinite confinement and donor impurity located at the cone apex. Coincidence is found to be remarkable.

وصف الملف: electronic resource

العلاقة: http://www.sciencedirect.com/science/article/pii/S2405844020300396Test; https://doaj.org/toc/2405-8440Test

الوصول الحر: https://doaj.org/article/66a89b478b6d442aa1645df8c0515685Test

المؤلفون: El Aouami, Camelia, Louhmadi, Abdeljalil

المصدر: European Journal of Business and Management Research ; volume 5, issue 5 ; ISSN 2507-1076

الوصف: The development of the tourism sector in Morocco is faced with a double challenge of competitiveness and attractiveness. In order to strengthen these two variables, it is necessary to adopt an analytical approach which is based on regional advantages of the country according to an integrated territorial dimension. The main challenges of this approach revolve around the developed tourist accommodation capacities, both quantitatively and qualitatively, internal micro-projects, small and medium-sized companies able to carry out concrete actions to develop the sector competitiveness, and to counteract poverty. In order to answer to the aforementioned challenges, the Moroccan government, under the high patronage of HM the King, is conducting a prospective study on Moroccan tourism by 2030 with a view to capitalize on the 2020 and 2010 visions’ achievements. Both first visions are part of a structuring approach in terms of employment, namely Azure 2020, Patrimony & heritage, Eco & sustainable development, Animation, Sports & leisure and Biladi - Internal tourism. However, the Vision 2030 is not just function of incomes and prices, but other long term change factors that may affect or associate with human needs.

الإتاحة: https://doi.org/10.24018/ejbmr.2020.5.5.566Test
https://www.ejbmr.org/index.php/ejbmr/article/download/566/324Test

المؤلفون: El Aouami, A., Bikerouin, M., El-Yadri, M., Feddi, E., Dujardin, F., Courel, M., Chouchen, B., Gazzah, M.H., Belmabrouk, H.

المصدر: Solar Energy ; volume 201, page 339-347 ; ISSN 0038-092X

مصطلحات موضوعية: General Materials Science, Renewable Energy, Sustainability and the Environment

الإتاحة: https://doi.org/10.1016/j.solener.2020.03.011Test
https://api.elsevier.com/content/article/PII:S0038092X20302425?httpAccept=text/xmlTest
https://api.elsevier.com/content/article/PII:S0038092X20302425?httpAccept=text/plainTest

المؤلفون: Mora-Ramos, M.E., El Aouami, A., Feddi, E., Radu, A., Restrepo, R.L., Vinasco, J.A., Morales, A.L., Duque, C.A.

المساهمون: Consejo Nacional de Ciencia y Tecnología

المصدر: Heliyon ; volume 6, issue 1, page e03194 ; ISSN 2405-8440

مصطلحات موضوعية: Multidisciplinary

الإتاحة: https://doi.org/10.1016/j.heliyon.2020.e03194Test
https://api.elsevier.com/content/article/PII:S2405844020300396?httpAccept=text/xmlTest
https://api.elsevier.com/content/article/PII:S2405844020300396?httpAccept=text/plainTest

المؤلفون: El Aouami, A., Feddi, K., El Haouari, M., El Yadri, M., Ben Afkir, N., Zazoui, M., Feddi, E., Duque, C.A., Dujardin, F.

المساهمون: Laboratoire de Matière Condensée et Sciences Interdisciplinaires (LaMCScI), Université Mohammed V de Rabat Agdal (UM5), Université Internationale de Rabat (UIR), Faculté des sciences et Techniques de Tanger, Abdelmalek Essaadi University Tétouan = Université Abdelmalek Essaadi Tétouan (UAE), Centre Régional des Métiers de l′Education et de Formation de Tanger (CRMEF), Laboratory of Physics of Condensed Matter and Renewable Energy, Faculty of Sciences and Technology, Hassan II University of Casablanca, Universidad de Antoquia, Laboratoire de Chimie et Physique - Approche Multi-échelle des Milieux Complexes (LCP-A2MC), Université de Lorraine (UL)

المصدر: ISSN: 0749-6036.

مصطلحات موضوعية: Solar cells, Photovoltaic, Quantum dots, Intermediate band, Conversion efficiency, Temperature effect, [PHYS]Physics [physics], [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat]

الوصف: International audience ; We report a theoretical investigation of the photovoltaic conversion efficiency of solar cells based on the introduction of quantum dot supracrystals arrayed in the i-region of a photodiode. The position and width of intermediate bands induced by the discrete quantized energy levels of electrons and holes originating from QDs are determined by using the Kronig-Penney model. Thus, interband and intersubband transitions are determined for different dot sizes and inter-dot distances. Taking into account the hole level and its impact on the band offset usually neglected in the same studies, all characteristic parameters of the cell such as open circuit voltage, short circuit current density and photoelectric conversion efficiency are determined as a function of the -concentration, mean size and inter-dot spacing of QDs. The results show that the performances of this new generation of solar cell increase considerably and can be adjusted by controlling the size, inter-dot spacing and -concentration.

العلاقة: hal-02900876; https://hal.univ-lorraine.fr/hal-02900876Test; https://hal.univ-lorraine.fr/hal-02900876/documentTest; https://hal.univ-lorraine.fr/hal-02900876/file/S0749603619302496.pdfTest; PII: S0749-6036(19)30249-6

الإتاحة: https://doi.org/10.1016/j.spmi.2019.03.026Test
https://hal.univ-lorraine.fr/hal-02900876Test
https://hal.univ-lorraine.fr/hal-02900876/documentTest
https://hal.univ-lorraine.fr/hal-02900876/file/S0749603619302496.pdfTest

المؤلفون: El-Yadri, M., Feddi, E., Aghoutane, N., El Aouami, A., Radu, A., Dujardin, F., Nguyen, Chuong V., Phuc, Huynh V., Duque, C. A.

المصدر: Journal of Applied Physics; 2018, Vol. 124 Issue 14, pN.PAG-N.PAG, 7p, 1 Color Photograph, 1 Diagram, 1 Chart, 6 Graphs

مصطلحات موضوعية: SILICA, QUANTUM dots, QUANTUM confinement effects, BINDING energy, PHOTOLUMINESCENCE, OPTOELECTRONIC devices

مستخلص: This paper reports the numerical investigation of the quantum confinement effects on excitons in a S i cylindrical core/shell quantum dots. Using the effective-mass approximation and considering a variational technique, we have calculated the exciton ground state binding energy as functions of the shell size in order to study the behavior of the confined exciton into the region of a thin shell with rigid walls. Our results show that the core-shell sizes have a remarkable influence on the electron-hole interaction, which leads to a significant impact on the binding and the optical photoluminescence energies of exciton. Also, we found that the exciton binding energy is higher for the small shell sizes. The effects caused by quantum confinement in such quantum dot nanostructures offer an alternative way of tuning the excitonic transitions in optoelectronic semiconducting devices. [ABSTRACT FROM AUTHOR]

: Copyright of Journal of Applied Physics is the property of American Institute of Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

المؤلفون: Asmae El, Aouami, Laura M, Pérez, Kawtar, Feddi, Mohamed, El-Yadri, Francis, Dujardin, Manuel J, Suazo, David, Laroze, Maykel, Courel, El Mustapha, Feddi

المصدر: Nanomaterials

مصطلحات موضوعية: quantum dots, intermediate band solar cells, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, Article, power conversion efficiency

الوصف: Solar cells that are based on the implementation of quantum dots in the intrinsic region, so-called intermediate band solar cells (IBSCs), are among the most widely used concepts nowadays for achieving high solar conversion efficiency. The principal characteristics of such solar cells relate to their ability to absorb low energy photons to excite electrons through the intermediate band, allowing for conversion efficiency exceeding the limit of Shockley–Queisser. IBSCs are generating considerable interest in terms of performance and environmental friendliness. However, there is still a need for optimizing many parameters that are related to the solar cells, such as the size of quantum dots, their shape, the inter-dot distance, and choosing the right material. To date, most studies have only focused on studying IBSC composed of cubic shape of quantum dots. The main objective of this study is to extend the current knowledge of IBSC. Thus, we analyze the effect of the shape of the quantum dot on the electronic and photonic characteristics of indium nitride and indium gallium nitride multiple quantum dot solar cells structure considering cubic, spherical, and cylindrical quantum dot shapes. The ground state of electrons and holes energy levels in quantum dot are theoretically determined by considering the Schrödinger equation within the effective mass approximation. Thus, the inter and intra band transitions are determined for different dot sizes and different inter dot spacing. Consequently, current–voltage (J-V) characteristic and efficiencies of these devices are evaluated and compared for different shapes. Our calculations show that, under fully concentrated light, for the same volume of different quantum dots (QD) shapes and a well determined In-concentration, the maximum of the photovoltaic conversion efficiencies reaches 63.04%, 62.88%, and 62.43% for cubic, cylindrical, and spherical quantum dot shapes, respectively.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=pmid________::2c9b8597f922ad433c981e5d517cd7bdTest
https://pubmed.ncbi.nlm.nih.gov/34067706Test