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Öğe Boosting the efficiency of Cu2ZnSnS4 solar cells with VO2 phase transition photonic crystal(Elsevier, 2023) Basyooni, Mohamed A.; Houimi, Amina; Tihtih, Mohammed; Zaki, Shrouk E.; Boukhoubza, Issam; Belaid, Walid; En-nadir, RedouanePhotonic crystal (PhC) has been studied for their potential to improve the efficiency of Cu2ZnSnS4 solar cells by increasing the generated photocurrent by integrating it as a back reflector with almost zero transmission through the absorption active zone of the solar cell. It was found that the thickness of PhC layers greatly affects the width of the photonic bandgap and that increasing the thickness of VO2 causes it to shift to a higher wavelength range. The PhC layers were added at the back side of the solar cell in two different configurations: (Monoclinic (M) VO2/TiO2) and (Tetragonal (T) VO2/TiO2) via SCAPS model. The study found that the (M VO2/TiO2) configuration led to an enhancement of the device's efficiency from 11.02 to 12.79%, while the (T VO2/TiO2) reaches 16.88%. The study concluded that the PhC layers enhance the light-matter coupling and photonic coupling and improvement in the device's performance.Öğe Development of Yttrium-Doped BaTiO3 for Next-Generation Multilayer Ceramic Capacitors(Amer Chemical Soc, 2023) Tihtih, Mohammed; Ibrahim, Jamal Eldin F. M.; Basyooni, Mohamed A.; En-nadir, Redouane; Belaid, Walid; Hussainova, Irina; Kocserha, IstvanThe use of electronic devices that incorporate multilayer ceramic capacitors (MLCCs) is on the rise, requiring materials with good electrical properties and a narrow band gap. This study synthesized yttrium-substituted barium titanate (Ba1-xYxTiO3, BYT) using a sol-gel process at 950 degrees C with varying concentrations of yttrium (0 < x < 0.3). X-ray diffraction analysis showed that the tetragonal phase became less pronounced as the yttrium content increased. The samples had varying grain sizes and porosity, with the BY30%T sample having the narrowest band gap at 2.21 eV. The BYT ceramic with 30% yttrium had a thermal conductivity of up to 7 W/m K and an electrical conductivity down to 0.002 (omega cm)-1 at 180 degrees C. The current-voltage characteristics of the BYT MLCC were also studied, showing potential use in next-generation high-capacity MLCCs. This work presents BYT as a promising material for these types of capacitors.Öğe Enhanced optical and thermal conductivity properties of barium titanate ceramic via strontium doping for thermo-optical applications(Springer, 2023) Tihtih, Mohammed; Ibrahim, Jamal Eldin F. M.; Basyooni, Mohamed A.; En-nadir, Redouane; Belaid, Walid; Abdelfattah, Mohamed M.; Hussainova, IrinaIn this study, we prepared a homogeneous fine powder of barium titanate (BaTiO3, BT) doped with different concentrations of strontium (x = 0, 0.05, 0.125, 0.15, 0.20, and 0.3) and having the composition Ba1-xSrxTiO3 (barium strontium titanate, BSrxT). XRD patterns and Rietveld refinement revealed the existence of a single tetragonal phase structure for BSrxT, x = 0-20%, and a single cubic structure for BSr30%T. The physical properties of the pure and doped mixtures were studied. The results showed that the addition of strontium to the physical properties of BaTiO3, including the apparent porosity, bulk density, linear shrinkage, and water absorption have been changed when increasing the Sr content. Moreover, the inclusion of 15% Sr in BaTiO3 increases the apparent porosity and water absorption of the sample to 6.2 and 28.5%, respectively. The optical properties were investigated by Ultraviolet-visible spectroscopy and it was found that the optical band gap decreases significantly with increasing Sr concentration, from 3.10 for pure BaTiO3 to 2.46 eV for the BSr30%T compound. The thermal conductivity measurements showed that the doping mechanism and the increased temperature have a significant effect on the thermal conductivity results of the fabricated ceramic materials. Therefore, it was found that the value of thermal conductivity increases with increasing Sr doping and at higher temperatures. A correlated behavior of optimum values is observed in band gap energy, absorption, and thermal conductivity which can be exploited for thermo-optical applications.Öğe Functionality and Activity of Sol-Gel-Prepared Co and Fe co-Doped Lead-Free BTO for Thermo-Optical Applications(Amer Chemical Soc, 2023) Tihtih, Mohammed; Ibrahim, Jamal Eldin F. M.; Basyooni, Mohamed A.; En-nadir, Redouane; Hussainova, Irina; Kocserha, IstvanThe BTO, BFTC, and BCTF compounds were synthesized by the sol- gel method. The XRD study revealed the formation of single-phase tetragonal perovskite structures with the space group (P4mm). The crystalline parameters were studied as a function of Fe and Co contents and occupation of Ba and/or Ti sites by Fe and Co in the BTO lattice. It was found that the obtained strain increases when Ba2+ is substituted by Co2+ and Ti4+ by Fe3+. The Raman investigation confirmed the existence of three active modes (B1/E (TO1LO), (E (TO)/A1(TO3), and (A 1(LO)/E (TO), all of which are related to the existence of the tetragonal phase and strongly support the XRD results. The microstructural study showed a clear correlation between the presence of Fe and Co and the grain size distribution. Optical studies revealed the improvement in band gap energy with transition-metal (Fe and Co) co-doped BTO ceramics. The decrease in the band gap is explained by the competing effects of Columbian interactions, microdeformation, and oxygen defects. The results indicate that the presence of Fe and Co dopants enhances the absorption in the BTO ceramic. The dopants demonstrated an effect on thermal conductivity: they decreased the thermal conductivity of BTO, which is in the range of 0.76-2.23 W m(-1) K-1 at room temperature and 2.02-0.27 W m(-1) K-1 at elevated temperatures. The microstructure of the manufactured materials and the grain size distribution affect the compressive strength.Öğe Impact of thickness on optoelectronic properties of ?-MoO3 film photodetectors: Integrating first-principles calculations with experimental analysis(Elsevier, 2023) Basyooni, Mohamed A.; Achehboune, Mohamed; Boukhoubza, Issam; Gaballah, A. E. H.; Tihtih, Mohammed; Belaid, Walid; En-nadir, RedouaneThis study focused on investigating the optoelectronic properties of molybdenum trioxide (alpha-MoO3) thin films using the atomic layer deposition (ALD) technique through different cycle numbers and theoretical investigation. Initial band gap calculations using standard DFT with GGA-PBE resulted in a value of 1.19 eV, which deviated significantly from experimental measurements. The GGA + U method with Hubbard U corrections was applied for the first time to improve the accuracy. This refinement led to a more precise band gap value of 3.09 eV, closely matching previously reported experimental data. The electronic parameters of the alpha-MoO3 photodetector, such as ideality factor (n), barrier height (phi 0), and series resistance (Rs), were analyzed using the thermionic emission theory and confirmed by Cheung and Nord's methods. The results demonstrated that the sample deposited with 100 pulses exhibited higher photodetector performance under UV illumination, despite having a lower Rs.Öğe Iridium/Silicon Ultrathin Film for Ultraviolet Photodetection: Harnessing Hot Plasmonic Effects(Wiley-V C H Verlag Gmbh, 2024) Basyooni, Mohamed A.; Tihtih, Mohammed; Boukhoubza, Issam; Ibrahim, Jamal Eldin F. M.; En-nadir, Redouane; Abdelbar, Ahmed M.; Rahmani, KhalidThe phenomenon of hot carriers, which are generated through the nonradiative decay of surface plasmons in ultrathin metallic films, offers an intriguing opportunity for subbandgap photodetection even at room temperature. These hot carriers possess sufficient energy to inject into the conduction band of a semiconductor material. The groundbreaking use of iridium (Ir) ultrathin film as an ultraviolet (UV) plasmonic material on silicon (Si) for high-performance photodetectors (PHDs) has been successfully demonstrated. Elevating the thickness of the sputtered Ir film to 4 nm yields a notable surge in photocurrent, registering an impressive 600 & mu;A under 365 nm UV illumination with electron mobility of 1.37E3 cm2 V-1 s. This PHD exhibits excellent OFF-ON photoresponses at various applied voltages ranging from 0 to 5 V, maintaining a stable photocurrent. Under UV illumination, it displays exceptional performance, achieving a high detectivity of 1.25E14 Jones and a responsivity of 1.28 A W-1. These outstanding results underscore the significant advantages of increasing the thickness of the Ir film in PHDs, leading to improvements in conductivity, detectivity, external quantum efficiency, responsivity, as well as superior sensitivity for light detection. Exploring hot plasmon effects in iridium/silicon ultrathin films: This study delves into a remarkable ultrasmooth iridium thin film's application in hot electron plasmonic photodetectors. Exciting strides in optoelectronic devices are anticipated, owing to their capability for efficient light modulation, absorption, and conversion, with implications for photodetection and solar energy transformation.image & COPY; 2023 WILEY-VCH GmbHÖğe Negative Photoconductivity in 2D ?-MoO3/Ir Self-Powered Photodetector: Impact of Post-Annealing(Mdpi, 2023) Basyooni-M. Kabatas, Mohamed A.; Zaki, Shrouk E.; Rahmani, Khalid; En-nadir, Redouane; Eker, Yasin RamazanSurface plasmon technology is regarded as having significant potential for the enhancement of the performance of 2D oxide semiconductors, especially in terms of improving the light absorption of 2D MoO3 photodetectors. An ultrathin MoO3/Ir/SiO2/Si heterojunction Schottky self-powered photodetector is introduced here to showcase positive photoconductivity. In wafer-scale production, the initial un-annealed Mo/2 nm Ir/SiO2/Si sample displays a sheet carrier concentration of 5.76 x 10(11)/cm(2), which subsequently increases to 6.74 x 10(12)/cm(2) after annealing treatment, showing a negative photoconductivity behavior at a 0 V bias voltage. This suggests that annealing enhances the diffusion of Ir into the MoO3 layer, resulting in an increased phonon scattering probability and, consequently, an extension of the negative photoconductivity behavior. This underscores the significance of negative photoconductive devices in the realm of optoelectronic applications.Öğe Numerical Analysis of InGaN/GaN Intermediate Band Solar Cells Under X-sun Concentration, In-compositions, and Doping: Unlocking the Potential of Concentrated Photovoltaics(Springer Heidelberg, 2024) El Ghazi, Haddou; Ramazan, Yasin Ecker; En-nadir, RedouaneOur research focuses on advancing solar energy through the study of nano- and microelectronic structures. Using the finite element method, we analyze key characteristics of InGaN/GaN intermediate band solar cells (IBSC), including refractive index, absorption coefficient, short-circuit current, open-circuit voltage, fill factor, and efficiency with a focus on the X-sun concentration effect. We assess nonpolar solar cell performance at room temperature and incorporate experimental data from American Society for Testing and Materials (ASTM), encompassing AM1.5D, AM1.5G, and AM0, to analyze refractive and absorption spectra. Investigating constraints on solar cell efficiency, we find that under AM1.5G spectra, the short-circuit current is higher compared to AM1.5D and AM0. Additionally, open-circuit voltage, fill factor, and efficiency increase significantly with elevated X-sun concentration and doping. Our analysis of ASTM data indicates that InGaN-based IBSC are efficiently able to absorb the visible spectrum and withstand intense X-sun concentration, making them suitable for concentrated photovoltaic technology.Öğe Positive and Negative Photoconductivity in Ir Nanofilm-Coated MoO3 Bias-Switching Photodetector(Mdpi, 2023) Kabatas, Mohamed A. Basyooni-M.; En-nadir, Redouane; Rahmani, Khalid; Eker, Yasin RamazanIn this study, we delved into the influence of Ir nanofilm coating thickness on the optical and optoelectronic behavior of ultrathin MoO3 wafer-scale devices. Notably, the 4 nm Ir coating showed a negative Hall voltage and high carrier concentration of 1.524 x 10(19) cm(-3) with 0.19 nm roughness. Using the Kubelka-Munk model, we found that the bandgap decreased with increasing Ir thickness, consistent with Urbach tail energy suggesting a lower level of disorder. Regarding transient photocurrent behavior, all samples exhibited high stability under both dark and UV conditions. We also observed a positive photoconductivity at bias voltages of >0.5 V, while at 0 V bias voltage, the samples displayed a negative photoconductivity behavior. This unique aspect allowed us to explore self-powered negative photodetectors, showcasing fast response and recovery times of 0.36/0.42 s at 0 V. The intriguing negative photoresponse that we observed is linked to hole self-trapping/charge exciton and Joule heating effects.Öğe Self-Powered UV Photodetector Utilizing Plasmonic Hot Carriers in 2D ?-MoO3/Ir/Si Schottky Heterojunction Devices(Wiley-V C H Verlag Gmbh, 2024) Basyooni, Mohamed A.; Zaki, Shrouk E.; Tihtih, Mohammed; Boukhoubza, Issam; En-nadir, Redouane; Derkaoui, Issam; Attia, Gamal F.Self-powered UV sensing has enormous potential in military and civilian applications. However, achieving high responsivity and fast response/recovery time presents significant challenges. Self-powered photodetectors (PDs) have several advantages over traditional PDs, including higher sensitivity, lower power consumption, and simpler design. This study introduces a breakthrough self-powered PD that uses a Schottky junction of 2D alpha-MoO3/iridium (Ir)/Si ultrathin film to detect 365 nm light at 0 V bias through using atomic layer deposition (ALD) and sputtering systems. The PD response is enhanced by plasmonic Ir-induced hot carriers, enabling detection in a mere 0.1 ms. Incorporating a 4 nm Ir layer boosts the responsivity from 0 to 34 A W-1, and the external quantum efficiency is elevated from 0 to 7E11 under 365 nm light illumination. It also has a high I-ON/I-OFF ratio of 11.22E4 at 0 V. These results make the MoO3/4 nm Ir/Si structure an interesting option for self-powered PDs with high efficiency, and the use of a simple ALD system for large-scale fabrication of 2D alpha-MoO3 on hot carrier Ir plasmonic layer. The findings of this research hold tremendous promise in the field of UV sensing and can lead to exciting developments in military and civilian technology.
