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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 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 Observation of negative photoresponse in joule-heated Au/Cu2SnS3 ternary chalcogenide thin film deposited by low energy pulsed laser deposition(Elsevier, 2022) Basyooni, Mohamed A.; Belaid, Walid; Houimi, Amina; Zaki, Shrouk E.; Eker, Yasin Ramazan; Gezgin, Serap Yigit; Kilic, Hamdi SukurGold (Au) nanoparticles trapped within Cu2SnS3 (CTS) thin films were effectively deposited on a low-cost glass substrate using a simple pulsed laser deposition of 15 mJ for 5 ns at a 10 Hz repetition rate. The film's structural, morphological, topography, optical, and optoelectronic properties were investigated. Highly crystalline ternary chalcogenide CTS with tetragonal symmetry and 17 nm grain size is prepared. The 110 0 resistivity of the thin film increases up to 125 0 indicating a negative photoresponse under visible light excitation. The decrease in the photocurrent is also observed with Cu2SnS3/Au/Cu2SnS3 sandwich ternary chalcogenide structure at resistivities values from 31 to 35 0 and a Joule effect influence the presence of plasmonic Au nanoparticle interlayers involved a lower phonon disorder given a higher photoresponse effect as predicted from Urbach energy.Öğe Reduced graphene oxide-functionalized zinc oxide nanorods as promising nanocomposites for white light emitting diodes and reliable UV photodetection devices(Elsevier Science Sa, 2023) Boukhoubza, Issam; Derkaoui, Issam; Basyooni, Mohamed A.; Achehboune, Mohamed; Khenfouch, Mohammed; Belaid, Walid; Enculescu, MonicaWe present a breakthrough in the development of novel nanocomposites based on reduced graphene oxide (RGO)-functionalized zinc oxide (ZnO) nanorods that hold exceptional promise for their use in white light emitting diodes (LEDs) and reliable UV photodetection. The nanorods had a pristine hexagonal wurtzite struc-ture, as confirmed by XRD analysis. SEM images revealed sandwich-like nanocomposites with ZnO nanorods coated in reduced graphene oxide and embedded between two layers of RGO. The study also confirmed the hybridization and interactions between the layers using Raman measurements. The resulting nanocomposites displayed a lower band gap energy than ZnO and exhibited unique photoluminescence spectra with a white PL light. The photodetector based on RGO/ZnO/RGO sandwich structures demonstrated exceptional photoresponse, with higher photocurrent under UV illumination, making it highly promising for a wide range of optoelectronic applications. Overall, this study offers a novel and powerful approach to create nanocomposite structures with enhanced optical characteristics.Öğe Role of A-site (Sr), B-site (Y), and A, B sites (Sr, Y) substitution in lead-free BaTiO3 ceramic compounds: Structural, optical, microstructure, mechanical, and thermal conductivity properties(Elsevier, 2023) Tihtih, Mohammed; Ibrahim, Jamal Eldin F. M.; Basyooni, Mohamed A.; Kurovics, Emese; Belaid, Walid; Hussainova, Irina; Kocserha, IstvanStrontium and Yttrium-doped and co-doped BaTiO3 (BT) ceramics with the stoichiometric formulas BaTiO3, B1-xSrxTiO3, Ba1-xYxTiO3, BaTi1-xYxO3, Ba1-xYxTi1-xYxO3, and Ba1-xSrxTi1-xYxO3 (x = 0.075) noted as BT, BSrT, BYT, BTY, BYTY, and BSrTY have been synthesized through sol-gel method. X-ray diffraction (XRD) patterns of the prepared ceramics, calcined at a slightly low temperature (950 degrees C/3h), displayed that BT, BSrT, and BYT ceramics possess tetragonal structures and BTY, BYTY, and BSrTY have a cubic structure. The incorporation of the Ba and/or Ti sites by Sr2+ and Y3+ ions in the lattice of BaTiO3 ceramic and the behaviors of the crystalline characteristics in terms of the Y and Sr dopant were described in detail. The scanning electron microscopy (SEM) images demonstrated that the densification and grain size were strongly related to Sr and Y elements. UV-visible spectroscopy was used to study the optical behavior of the as-prepared ceramic samples and revealed that Sr and Y dopants reduce the optical band gap energy to 2.74 eV for the BSrTY compound. The outcomes also demonstrated that the levels of Urbach energy are indicative of the created disorder following the inclusion of Yttrium. The measurements of the thermal conductivity indicated the influence of the doping mechanism on the thermal conductivity results of the synthesized samples. Indeed, the thermal conductivity of BaTiO3 is decreased with Sr and Y dopants and found to be in the range of 085-2.23 W.m(-1). K-1 at room temperature and decreases slightly with increasing temperature from 2.02 to 0.73-W.m(-1). K-1. Moreover, the microstructure and grains distribution of the BT, BSrT, BYT, BTY, BYTY, and BSrTY samples impacted the compressive strength, hence; the compressive strength was minimized as the grain size decreased.Öğe Structural, optical, and electronic properties of barium titanate: experiment characterisation and first-principles study(Taylor & Francis Ltd, 2022) Tihtih, Mohammed; Ibrahim, Jamal Eldin F. M.; Basyooni, Mohamed A.; Belaid, Walid; Gomze, Laszlo A.; Kocserha, IstvanTo study the structural, electronic, and optical properties of lead-free Barium titanate BaTiO3 (BT) ferroelectric material in its tetragonal structure, a combination of experimental and theoretical studies has been used and the obtained results were discussed. The studied BT compound was prepared via the sol-gel technique. The calculated bandgap energy (E-g) and structural parameters of BT are determined using four types of exchange-correlation functionals (PBE, PBEsol, LDA, and PW91) in the perspective of the density functional theory (DFT). XRD and Raman analysis have shown that BT ceramic exhibits a tetragonal phase structure without any trace of impurity phases. The UV-vis investigation showed that BT has a bandgap energy of 3.19 eV, which is larger than the theoretically calculated values. The computed lattice parameter c is overestimated (as large as similar to 1% deviation) when using the LDA approximation. In contrast, PBEsol proved that those lattice constants were close to the experimental values (a deviation of less than 1%).Öğe A theoretical study of the effects of electric field, hydrostatic pressure, and temperature on photoionization cross-section of a donor impurity in (Al, Ga)N/AlN double triangular quantum wells(Iop Publishing Ltd, 2023) Belaid, Walid; El Ghazi, Haddou; Zaki, Shrouk E.; Basyooni, Mohamed A.; Tihtih, Mohammed; Ennadir, Redouane; Kilic, Hamdi SukurThe aim of this research is to analyze the influence of various factors on the photo-ionization cross-section in (Al, Ga)N/AlN double triangular quantum wells. Using the finite difference method, the effects of the electric field, hydrostatic pressure, temperature, and Ga concentration were investigated within the effective mass and parabolic approximations. Our findings show that the photo-ionization cross-section (PICS) is highly dependent on all the variables under consideration. The optical spectra were blue-shifted with increasing electric field and pressure and red-shifted with increasing temperature and impurity displacement far from the center of the structure. Furthermore, it was found that changes in gallium content and impurity position can increase the PICS amplitude. A comparison of the obtained results with the existing literature as a limiting case of the reported problem is also provided, and excellent agreement is found.
