Yazar "Tihtih, Mohammed" seçeneğine göre listele

Listeleniyor 1 - 14 / 14
  • Küçük Resim Yok
    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, Redouane
    Photonic 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.
  • Küçük Resim Yok
    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, Istvan
    The 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.
  • Küçük Resim Yok
    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, Irina
    In 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.
  • Küçük Resim Yok
    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, Istvan
    The 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.
  • Küçük Resim Yok
    Öğe
    High-Performance Negative Self-Powered ?-MoO3/Ir/?-MoO3 Photodetectors: Probing the Influence of Coulomb Deep Traps
    (Amer Chemical Soc, 2023) Basyooni, Mohamed A.; Tihtih, Mohammed; Zaki, Shrouk E.; Eker, Yasin Ramazan
    Nanostructures of ultrathin 2D MoO3 semiconductors have gained significant attention in the field of transparent optoelectronics and nanophotonics due to their exceptional responsiveness. In this study, we investigate self-powered alpha-MoO3/Ir/alpha-MoO3 photodetectors, focusing on the influence of induced hot electrons in ultrathin alpha-MoO3 when combined with an ultrathin Ir plasmonic layer. Our results reveal the presence of both positive and negative photoconductivity at a 0 V bias voltage. Notably, by integrating a 2 nm Ir layer between post-annealed alpha-MoO3 films, we achieve remarkable performance metrics, including a high I-ON/I-OFF ratio of 3.8 x 10(6), external quantum efficiency of 132, and detectivity of 3.4 x 10(11) Jones at 0 V bias. Furthermore, the response time is impressively short, with only 0.2 ms, supported by an exceptionally low MoO3 surface roughness of 0.1 nm. The observed negative photoresponse is attributed to O-2 desorption from the MoO3 surface, resulting in increased carrier density and reduced mobility in the Ir layer due to Coulomb trapping and oxygen vacancy deep levels. Consequently, this leads to a decreased carrier mobility and diminished current in the heterostructure. Our findings underscore the enormous potential of ultrathin MoO3 semiconductors for high-performance negative conductivity optoelectronics and photonic applications.
  • Küçük Resim Yok
    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, Redouane
    This 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.
  • Küçük Resim Yok
    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, Khalid
    The 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 GmbH
  • Küçük Resim Yok
    Öğe
    Nanostructured MoS2 and WS2 Photoresponses under Gas Stimuli
    (Mdpi, 2022) Basyooni, Mohamed A.; Zaki, Shrouk E.; Alfryyan, Nada; Tihtih, Mohammed; Eker, Yasin Ramazan; Attia, Gamal F.; Yilmaz, Mucahit
    This study was on the optoelectronic properties of multilayered two-dimensional MoS2 and WS2 materials on a silicon substrate using sputtering physical vapor deposition (PVD) and chemical vapor deposition (CVD) techniques. For the first time, we report ultraviolet (UV) photoresponses under air, CO2, and O-2 environments at different flow rates. The electrical Hall effect measurement showed the existence of MoS2 (n-type)/Si (p-type) and WS2 (P-type)/Si (p-type) heterojunctions with a higher sheet carrier concentration of 5.50 x 10(5) cm(-2) for WS2 thin film. The IV electrical results revealed that WS2 is more reactive than MoS2 film under different gas stimuli. WS2 film showed high stability under different bias voltages, even at zero bias voltage, due to the noticeably good carrier mobility of 29.8 x 10(2) cm(2)/V. WS2 film indicated a fast rise/decay time of 0.23/0.21 s under air while a faster response of 0.190/0.10 s under a CO2 environment was observed. Additionally, the external quantum efficiency of WS2 revealed a remarkable enhancement in the CO2 environment of 1.62 x 10(8) compared to MoS2 film with 6.74 x 10(6). According to our findings, the presence of CO2 on the surface of WS2 improves such optoelectronic properties as photocurrent gain, photoresponsivity, external quantum efficiency, and detectivity. These results indicate potential applications of WS2 as a photodetector under gas stimuli for future optoelectronic applications.
  • Küçük Resim Yok
    Öğe
    Photonic bandgap engineering in (VO2) n /(WSe2) n photonic superlattice for versatile near- and mid-infrared phase transition applications
    (Iop Publishing Ltd, 2022) Basyooni, Mohamed A.; Zaki, Shrouk E.; Tihtih, Mohammed; Eker, Yasin Ramazan; Ates, Sule
    The application of the photonic superlattice in advanced photonics has become a demanding field, especially for two-dimensional and strongly correlated oxides. Because it experiences an abrupt metal-insulator transition near ambient temperature, where the electrical resistivity varies by orders of magnitude, vanadium oxide (VO2) shows potential as a building block for infrared switching and sensing devices. We reported a first principle study of superlattice structures of VO2 as a strongly correlated phase transition material and tungsten diselenide (WSe2) as a two-dimensional transition metal dichalcogenide layer. Based on first-principles calculations, we exploit the effect of semiconductor monoclinic and metallic tetragonal state of VO2 with WSe2 in a photonic superlattices structure through the near and mid-infrared (NIR-MIR) thermochromic phase transition regions. By increasing the thickness of the VO2 layer, the photonic bandgap (PhB) gets red-shifted. We observed linear dependence of the PhB width on the VO2 thickness. For the monoclinic case of VO2, the number of the forbidden bands increase with the number of layers of WSe2. New forbidden gaps are preferred to appear at a slight angle of incidence, and the wider one can predominate at larger angles. We presented an efficient way to control the flow of the NIR-MIR in both summer and winter environments for phase transition and photonic thermochromic applications. This study's findings may help understand vanadium oxide's role in tunable photonic superlattice for infrared switchable devices and optical filters.
  • Küçük Resim
    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, Istvan
    Strontium 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.
  • Küçük Resim Yok
    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.
  • Küçük Resim Yok
    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, Istvan
    To 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%).
  • Küçük Resim Yok
    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 Sukur
    The 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.
  • Küçük Resim Yok
    Öğe
    Thermionic Emission of Atomic Layer Deposited MoO3/Si UV Photodetectors
    (Mdpi, 2023) Basyooni, Mohamed A.; Gaballah, A. E. H.; Tihtih, Mohammed; Derkaoui, Issam; Zaki, Shrouk E.; Eker, Yasin Ramazan; Ates, Sule
    Ultrathin MoO3 semiconductor nanostructures have garnered significant interest as a promising nanomaterial for transparent nano- and optoelectronics, owing to their exceptional reactivity. Due to the shortage of knowledge about the electronic and optoelectronic properties of MoO3/n-Si via an ALD system of few nanometers, we utilized the preparation of an ultrathin MoO3 film at temperatures of 100, 150, 200, and 250 degrees C. The effect of the depositing temperatures on using bis(tbutylimido)bis(dimethylamino)molybdenum (VI) as a molybdenum source for highly stable UV photodetectors were reported. The ON-OFF and the photodetector dynamic behaviors of these samples under different applied voltages of 0, 0.5, 1, 2, 3, 4, and 5 V were collected. This study shows that the ultrasmooth and homogenous films of less than a 0.30 nm roughness deposited at 200 degrees C were used efficiently for high-performance UV photodetector behaviors with a high sheet carrier concentration of 7.6 x 10(10) cm(-2) and external quantum efficiency of 1.72 x 10(11). The electronic parameters were analyzed based on thermionic emission theory, where Cheung and Nord's methods were utilized to determine the photodetector electronic parameters, such as the ideality factor (n), barrier height (f(0)), and series resistance (R-s). The n-factor values were higher in the low voltage region of the I-V diagram, potentially due to series resistance causing a voltage drop across the interfacial thin film and charge accumulation at the interface states between the MoO3 and Si surfaces.