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1.
Sci Rep ; 14(1): 15510, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38969827

RESUMEN

The optoelectronic and structural characteristics of the Zn1-xCrxSe (0 ≤ x ≤ 1) semiconductor are reported by employing density functional theory (DFT) within the mBJ potential. The findings revealed that the lattice constant decreases with increasing Cr concentration, although the bulk modulus exhibits the opposite trend. ZnSe is a direct bandgap material; however, a change from direct to indirect electronic bandgap has been seen with Cr presence. This transition is caused by structural alterations by Cr and defects forming, which results in novel optical features, including electronic transitions. The electronic bandgap decreases from 2.769 to 0.216 eV, allowing phonons to participate and improving optical absorption. A higher concentration of Cr boosts infrared absorption and these Cr-based ZnSe (ZnCrSe) semiconductors also cover a wider spectrum in the visible range from red to blue light. Important optical parameters such as reflectance, optical conductivity, optical bandgap, extinction coefficient, refractive index, magnetization factor, and energy loss function are discussed, providing a theoretical understanding of the diverse applications of ZnCrSe semiconductors in photonic and optoelectronic devices.

2.
Heliyon ; 10(11): e31957, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38867975

RESUMEN

Background: Lactic acid bacteria (LAB) are utilized as a starter culture in the manufacturing of fermented dairy items, as a preservative for various food products, and as a probiotic. In our country, some research has been carried out, even if LAB plays a principal role in food preservation and improves the texture and taste of fermented foods, that is why we tried to evaluate their probiotic effect. The objective of this research was to determine the antibacterial activity of Lactococcus lactis (L. lactis) against Staphylococcus aureus (S. aureus) ATCC 29213, investigate their antioxidant activity, and characterize their sensitivity against 18 antibiotics. Methods: A total of 23 LAB (L. lactis subsp. cremoris, L. lactis subsp. Lactis diacetylactis, L. lactis subsp. lactis) were isolated from cow's raw milk. The antibacterial activity was performed using two techniques, competition for nutrients and a technique utilizing components nature, using the disk diffusion method. The sensitivity of the studied LAB to different antibiotics was tested on Man rogosa sharp (MRS) agar using commercial antibiotic disks. All strains of LAB were examined for their antioxidant activity. The antioxidant activity of L. lactis was tested by 2,2-diphenyl-1 picrylhydrazyl (DPPH). Results: The results showed that the MRS medium was more adapted than Muller Hinton Agar (MHA) to investigate the antibacterial activity of L. lactis against S. aureus ATCC 29213. Also, L. lactis exhibited a notable degree of antibacterial activity against S. aureus ATCC 29213. L. Lactis subsp. Lactis displayed higher antibacterial activities, followed by L. lactis ssp. lactis biovar. diacetylactis, and lastly, L. lactis ssp. cremoris against S. aureus ATCC 29213. Lc 26 among all strains of L. lactis showed a high potential antibacterial activity reaching 40 ± 3 mm against S. aureus ATCC 29213. All strains of L. lactis showed a slightly moderate antioxidant activity (10.56 ± 1.28%-26.29 ± 0.05 %). The results of the antibiotic resistance test indicate that all strains of L. lactis were resistant to cefotaxime, sulfamethoxazole-trimethoprim, and streptomycin and were sensitive to Ampicillin, Amoxicillin, Penicillin G, Teicoplanin, Vancomycin, Gentamicin 500, Tetracycline, and Chloramphenicol. These test results indicate that this strain falls within the criteria of not posing any harmful effects on human health. The important antibacterial properties recorded for all L. Lactis strains were derived from the production of antibacterial active metabolites, such as protein, diacetyl, hydrogen peroxide, and lactic acid, together with the fight for nutrients. Conclusion: This study suggests that the strains of L. lactis could be added as an antibacterial agent against S. aureus ATCC 29213 and can provide an important nutritional property for their antioxidant potential.

3.
Int J Nanomedicine ; 19: 5813-5835, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38895143

RESUMEN

Breast and ovarian cancers, despite having chemotherapy and surgical treatment, still have the lowest survival rate. Experimental stages using nanoenzymes/nanozymes for ovarian cancer diagnosis and treatment are being carried out, and correspondingly the current treatment approaches to treat breast cancer have a lot of adverse side effects, which is the reason why researchers and scientists are looking for new strategies with less side effects. Nanoenzymes have intrinsic enzyme-like activities and can reduce the shortcomings of naturally occurring enzymes due to the ease of storage, high stability, less expensive, and enhanced efficiency. In this review, we have discussed various ways in which nanoenzymes are being used to diagnose and treat breast and ovarian cancer. For breast cancer, nanoenzymes and their multi-enzymatic properties can control the level of reactive oxygen species (ROS) in cells or tissues, for example, oxidase (OXD) and peroxidase (POD) activity can be used to generate ROS, while catalase (CAT) or superoxide dismutase (SOD) activity can scavenge ROS. In the case of ovarian cancer, most commonly nanoceria is being investigated, and also when folic acid is combined with nanoceria there are additional advantages like inhibition of beta galactosidase. Nanocarriers are also used to deliver small interfering RNA that are effective in cancer treatment. Studies have shown that iron oxide nanoparticles are actively being used for drug delivery, similarly ferritin carriers are used for the delivery of nanozymes. Hypoxia is a major factor in ovarian cancer, therefore MnO2-based nanozymes are being used as a therapy. For cancer diagnosis and screening, nanozymes are being used in sonodynamic cancer therapy for cancer diagnosis and screening, whereas biomedical imaging and folic acid gold particles are also being used for image guided treatments. Nanozyme biosensors have been developed to detect ovarian cancer. This review article summarizes a detailed insight into breast and ovarian cancers in light of nanozymes-based diagnostic and therapeutic approaches.


Asunto(s)
Neoplasias de la Mama , Neoplasias Ováricas , Humanos , Femenino , Neoplasias Ováricas/terapia , Neoplasias Ováricas/diagnóstico , Neoplasias de la Mama/terapia , Nanopartículas/química , Especies Reactivas de Oxígeno/metabolismo , Enzimas/metabolismo , Enzimas/química , Detección Precoz del Cáncer/métodos , Animales , Cerio
4.
Molecules ; 29(9)2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38731594

RESUMEN

The current study explores the prospective of a nitrogen-doped graphene (NG) incorporated into ZnSe-TiO2 composites via hydrothermal method for supercapacitor electrodes. Structural, morphological, and electronic characterizations are conducted using XRD, SEM, Raman, and UV analyses. The electrochemical study is performed and galvanostatic charge-discharge (GCD) and cyclic voltammetry (CV) are evaluated for the supercapacitor electrode material. Results demonstrate improved performance in the ZnSe-NG-TiO2 composite, indicating its potential for advanced supercapacitors with enhanced efficiency, stability, and power density. Specific capacity calculations and galvanic charge-discharge experiments confirmed the promising electrochemical activity of ZnSe-NG-TiO2, which has a specific capacity of 222 C/g. The negative link among specific capacity and current density demonstrated the composite's potential for high energy density and high-power density electrochemical devices. Overall, the study shows that composite materials derived from multiple families can synergistically improve electrode characteristics for advanced energy storage applications.

5.
ACS Omega ; 9(16): 18202-18211, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38680326

RESUMEN

In this study, solar cells based on pure Cs2AgBiBr6 and Al-doped metal were fabricated using the sol-gel spin-coating technique. X-ray diffraction (XRD) analysis confirmed the formation of cubic-structured films for both pure and Al-doped. Notably, the grain size of Al-doped Cs2AgBiBr6 was observed to be larger than that of its pure counterpart. The optical properties of these films were investigated using UV-vis spectroscopy, revealing essential parameters such as the bandgap energy (Eg), refractive index (n), extinction coefficients (k), and dielectric constant. While the pure film exhibited an Eg of 1.91 eV, the Al-doped film demonstrated a slightly lower Eg of 1.82 eV. Utilization of these films in solar cell fabrication yielded intriguing results. The J-V curve shows that the pure solar cell displayed a short-circuit current density (Jsc) of 5.01 mA/cm2, a fill factor (FF) of 0.67, an open-circuit voltage (Voc) of 0.89 V, and an efficiency of 3.02%. Al doping led to improvements, with an increase in Voc to 0.91 V, FF to 0.71, and Jsc to 5.29 mA/cm2. Consequently, the overall efficiency surged to 3.40%, marking a substantial 12.5% enhancement compared with the pure solar cell. These findings underscore the efficacy of Al doping in enhancing the performance of Cs2AgBiBr6-based solar cells.

6.
RSC Adv ; 14(8): 5440-5448, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38348293

RESUMEN

Lead-free halide double perovskite (LFHDP) Cs2AgBiBr6 has emerged as a promising alternative to traditional lead-based perovskites (LBPs), offering notable advantages in terms of chemical stability and non-toxicity. However, the efficiency of Cs2AgBiBr6 solar cells faces challenges due to their wide bandgap (Eg). As a viable strategy to settle this problem, we consider optimization of the optical and photovoltaic properties of Cs2AgBiBr6 by Gallium (Ga) substitution. The synthesized Cs2Ag0.95Ga0.05BiBr6 is rigorously characterized by means of X-ray diffraction (XRD), UV-vis spectroscopy, and solar simulator measurements. XRD analysis reveals shifts in peak positions, indicating changes in the crystal lattice due to Ga substitution. The optical analysis demonstrates a reduction in the Eg, leading to improvement of the light absorption within the visible spectrum. Importantly, the Cs2Ag0.95Ga0.05BiBr6 solar cell exhibits enhanced performance, as evidenced by higher values of open circuit voltage (Voc), short-circuit current (Jsc), and fill factor (FF), which are 0.94 V, 6.01 mA cm-2, and 0.80, respectively: this results in an increased power conversion efficiency (PCE) from 3.51% to 4.52%. This research not only helps to overcome film formation challenges, but also enables stable Cs2Ag0.95Ga0.05BiBr6 to be established as a high-performance material for photovoltaic applications. Overall, our development contributes to the advancement of environmentally friendly solar technologies.

7.
Heliyon ; 10(4): e25591, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38370257

RESUMEN

The current study focuses the nanocomposites of Ag/WO3 was synthesized via hydrothermal method and extract of Aloe-vera gel was used. Various characterization techniques were used for the analysis of Ag/WO3 nanocomposites which includes SEM (scanning electron microscope), EDX (Energy dispersive spectroscopy), XRD (X-ray diffraction), FTIR (Fourier transform infrared), UV (ultraviolet-visible-spectroscopy) to tell about elemental composition, shape and crystalline structure, band gap, functional group. The presence of composition of elements O, W, Ag in Ag/WO3 nanocomposites was confirmed through EDX spectrum. The hexagonal crystal structure and the border peaks in Ag/WO3 nanocomposites were examined through XRD spectra. The Anti-oxidant activity was synthesized by using (DPPH) free Radical in Ag/WO3 nanocomposites. The outcomes of present study exhibited an excellent anti-oxidant activity and also indicated the reduction of stabilized free radical DPPH analysis using Aloe vera extract. The result revealed that the anti-oxidant activity of Ag/WO3 nanocomposites is essential for biomedical application and various industries.

8.
Molecules ; 28(23)2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-38067589

RESUMEN

In this study, silica-encapsulated gadolinium was doped in lanthanum strontium manganite nanoparticles (NPs) with different concentrations using the citrate-gel auto-combustion method. We focused on tuning the Curie temperature and enhancing the specific absorption rate (SAR) of silica-coated gadolinium-doped lanthanum strontium manganite NPs to make them suitable for self-controlled magnetic hyperthermia. The samples were characterized by using transmission electron microscopy (TEM), X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), and magnetic measurements to examine the structural, optical, and magnetic properties of the manganite NPs. While our results exhibit a successful doping of gadolinium in lanthanum strontium manganite NPs, we further prepared magnetic core NPs with sizes between 20 and 50 nm. The Curie temperature of the NPs declined with increasing gadolinium doping, making them promising materials for hyperthermia applications. The Curie temperature was measured using the magnetization (M-T) curve. Magnetic heating was carried out in an external applied AC magnetic field. Our present work proved the availability of regulating the Curie temperature of gadolinium-doped lanthanum strontium manganite NPs, which makes them promising candidates for self-controlled magnetic hyperthermia applications.

9.
Molecules ; 28(24)2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38138453

RESUMEN

Thin films of zinc oxide (ZnO) doped with transition metals have recently gained significant attention due to their potential applications in a wide range of optoelectronic devices. This study focuses on ZnO thin films doped with the transition metals Co, Fe, and Zr, exploring various aspects of their structural, morphological, optical, electrical, and photoluminescence properties. The thin films were produced using RF and DC co-sputtering techniques. The X-ray diffraction (XRD) analysis revealed that all the doped ZnO thin films exhibited a stable wurtzite crystal structure, showcasing a higher structural stability compared to the undoped ZnO, while the atomic force microscopy (AFM) imaging highlighted a distinctive granular arrangement. Energy-dispersive X-ray spectroscopy was employed to confirm the presence of transition metals in the thin films, and Fourier-transform infrared spectroscopy (FTIR) was utilized to investigate the presence of chemical bonding. The optical characterizations indicated that doping induced changes in the optical properties of the thin films. Specifically, the doped ZnO thin film's bandgap experienced a significant reduction, decreasing from 3.34 to 3.30 eV. The photoluminescence (PL) analysis revealed distinguishable emission peaks within the optical spectrum, attributed to electronic transitions occurring between different bands or between a band and an impurity. Furthermore, the introduction of these transition metals resulted in decreased resistivity and increased conductivity, indicating their positive influence on the electrical conductivity of the thin films. This suggests potential applications in solar cells and light-emitting devices.

10.
ACS Omega ; 8(45): 42390-42397, 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-38024666

RESUMEN

Manganese-doped bismuth ferrites were synthesized using the coprecipitation method with the green extract Azadirachta indica. Our incorporation of the transition element, manganese, into bismuth ferrites tackles the challenge of increased leakage current often observed in intrinsic bismuth ferrites. We gained key insights through a comprehensive examination of the structural, dielectric, and optical properties of these materials, utilizing Fourier transform infrared spectroscopy (FTIR), impedance spectroscopy, and UV-visible spectroscopy, respectively. The formation of an octahedral geometry was confirmed using the FTIR technique. UV-visible spectroscopy indicated that 2% Mn doping is optimal, while we obtained a low band gap energy (2.21 eV) and high refractive index (3.010) at this amount of doping. The manufactured materials exhibited the typical ferrite-like dielectric response, that is, the dielectric parameter gradually decreased as the frequency increased and then stayed constant in the high-frequency range. Using the diphenylpicrylhydrazyl (DPPH) free radical assay, we also examined the antioxidant activity of bismuth ferrites. We concluded that among different Mn-doped BiFeMnO3-based nanomaterials, the 2 wt % Mn-doped BiFeMnO3 shows the highest antioxidant activity. This finding substantiates the efficacy of the optimized material with regard to its potent antioxidant activity, positioning it as a promising candidate for potential biomedical applications.

11.
ACS Omega ; 8(39): 36321-36332, 2023 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-37810674

RESUMEN

This work is aimed at investigating the viability of utilizing cadmium sulfide (CdS) as a buffer layer in CdTe solar cells by analyzing and assessing its optical, photoluminescence, morphological, and electrical properties. These films were fabricated using a thermal coating technique. Optical microscopy was used to observe the changes in morphology resulting from the doping of rare-earth metals such as samarium (Sm) and lanthanum (La) to CdS, while the granular-like structure of the sample was confirmed by scanning electron microscopy. The objective of incorporating Sm and La ions into CdS was to enhance photoconductivity and optimize the optical bandgap, aiming to create a viable charge transport material for photovoltaic devices with enhanced efficiency. Through that process, a noticeable decrease in transmission, from approximately 80 to 68% in the visible region, was observed. Additionally, the bandgap value was reduced from 2.43 to 2.27 eV. Furthermore, during the analysis of the photoluminescence spectra, it was observed that emission peaks occurred in the visible region. These emissions were attributed to electronic transitions that took place via band-to-band and band-to-impurity interactions. The electrical measurements showed an enhancement in conductivity due to the decrease in the bandgap. This notable consequence of the doped materials suggests their utilization in photovoltaic systems.

12.
Nanomaterials (Basel) ; 13(17)2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-37686903

RESUMEN

Superconducting flux qubits have many advantages as a storage of quantum information, such as broad range tunability of frequency, small-size fabricability, and high controllability. In the flux qubit-oscillator, qubits are connected to SQUID resonators for the purpose of performing dispersive non-destructive readouts of qubit signals with high fidelity. In this work, we propose a theoretical model for analyzing quantum characteristics of a flux qubit-oscillator on the basis of quantum solutions obtained using a unitary transformation approach. The energy levels of the combined system (qubit + resonator) are analyzed in detail. Equally spaced each energy level of the resonator splits into two parts depending on qubit states. Besides, coupling of the qubit to the resonator brings about an additional modification in the split energy levels. So long as the coupling strength and the tunnel splitting are not zero but finite values, the energy-level splitting of the resonator does not disappear. We conclude that quantum nondemolition dispersive measurements of the qubit states are possible by inducing bifurcation of the resonator states through the coupling.

13.
Heliyon ; 9(6): e16772, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37303547

RESUMEN

Improvements of visible light activity, slow recombination rate, stability, and efficiency are major challenges facing photocatalyst technologies today. Utilizing heterostructures of g-C3N4 (bandgap ∼2.7eV) with Nb2O5 (bandgap ∼3.4eV) as an alternative materials for the first time, we tried to overcome such challenges in this work. Heterostructures of Nb2O5/g-C3N4 have been synthesized via hydrothermal technique. And then a time-resolved laser flash photolysis of those heterostructures has been analyzed, focusing on seeking how to improve photocatalytic efficiency for molecular hydrogen (H2) evolution. The transient absorption spectra and the lifetime of charge carriers at different wavelengths have been observed for Nb2O5/g-C3N4, where g-C3N4 was used for a control. The role of hole scavenger (methanol) has also been investigated for the purpose of boosting charge trapping and H2 evolution. The long lifetime of Nb2O5/g-C3N4 heterostructures (6.54165 µs) compared to g-C3N4 (3.1651897 µs) has successfully supported the increased H2 evolution of 75 mmol/h.g. An enhancement in the rate of H2 evolution (160 mmol/h.g) in the presence of methanol has been confirmed. This study not only deepens our understanding of the role of scavenger, but also enables a rigorous quantification of the recombination rate crucial for photocatalytic applications in relation with efficient H2 production.

14.
Sci Rep ; 13(1): 10431, 2023 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-37369767

RESUMEN

The increase in global energy consumption and the related ecological problems have generated a constant demand for alternative energy sources superior to traditional ones. This is why unlimited photon-energy harnessing is important. A notable focus to address this concern is on advancing and producing cost-effective low-loss solar cells. For efficient light energy capture and conversion, we fabricated a ZnPC:PC70BM-based dye-sensitized solar cell (DSSC) and estimated its performance using a solar cell capacitance simulator (SCAPS-1D). We evaluated the output parameters of the ZnPC:PC70BM-based DSSC with different photoactive layer thicknesses, series and shunt resistances, and back-metal work function. Our analyses show that moderate thickness, minimum series resistance, high shunt resistance, and high metal-work function are favorable for better device performance due to low recombination losses, electrical losses, and better transport of charge carriers. In addition, in-depth research for clarifying the impact of factors, such as thickness variation, defect density, and doping density of charge transport layers, has been conducted. The best efficiency value found was 10.30% after tweaking the parameters. It also provides a realistic strategy for efficiently utilizing DSSC cells by altering features that are highly dependent on DSSC performance and output.

15.
ACS Omega ; 8(17): 15450-15457, 2023 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-37151528

RESUMEN

This study reports the synthesis of ferric vanadate (FeVO4) via a facile hydrothermal method, focusing on demonstrating its exceptional electrochemical (EC) properties on detecting low-density ascorbic acid (AA). The phase purity, crystallinity, structure, morphology, and chemical compositional properties were characterized by employing X-ray diffraction, energy-dispersive X-ray spectroscopy, scanning electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy techniques. EC impedance spectroscopy and cyclic voltammetry techniques were also adopted in order to assess the EC response of a FeVO4-modified glassy carbon electrode for sensing AA at room temperature. The AA concentration range adopted in this experiment is 0.1-0.3 mM at a working electric potential of -0.13 V. The result showed functional excellence of this material for the EC determination of AA with good stability and reproducibility, promising its potentiality in connection with relevant sensing applications.

16.
ACS Omega ; 8(19): 17317-17326, 2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37214698

RESUMEN

The unique consequence of green synthesis is that the mediator plant is able to release chemicals that are efficacious as reducing as well as stabilizing agents. In this work, the fruit pulp and leaf essences of Cassia fistula have been used to manufacture silver nanoparticles through the green synthesis technique. The sculpturing of nanoparticles was accomplished by utilizing the reduction phenomenon that ensued due to the reaction between plant essences and the precursor solution. These biosynthesized silver nanoparticles were examined, where we used scanning electron microscopy, UV-vis spectroscopy, and X-ray diffraction techniques as means to analyze the structure, optical properties, and crystalline behavior, respectively. The absorption spectra for fruit and leaf extracts obtained from the UV-vis analyses peaked at 401 and 397 nm, and these peaks imply the appearance of optical energy gaps of 2.12 and 2.58 eV, accompanying spherical shapes of particles with diameters in the ranges of 12-20 and 50-80 nm, respectively. These silver nanoparticles together with the adopted green technique have a vast array of applications, specifically in the biomedical realm. In particular, they are being used to treat several diseases and are manifested as strong anti-tumor agents to medicate MCF-7 breast cancer cell lines in order to minimize the cell growth rate depending on their concentrations.

17.
Sci Rep ; 13(1): 3123, 2023 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-36813815

RESUMEN

This study reports light energy harvesting characteristics of bismuth ferrite (BiFeO3) and BiFO3 doped with rare-earth metals such as neodymium (Nd), praseodymium (Pr), and gadolinium (Gd) dye solutions that were prepared by using the co-precipitation method. The structural, morphological, and optical properties of synthesized materials were studied, confirming that 5-50 nm sized synthesized particles have a well-developed and non-uniform grain size due to their amorphous nature. Moreover, the peaks of photoelectron emission for bare and doped BiFeO3 were observed in the visible region at around 490 nm, while the emission intensity of bare BiFeO3 was noticed to be lower than that of doped materials. Photoanodes were prepared with the paste of the synthesized sample and then assembled to make a solar cell. The natural and synthetic dye solutions of Mentha, Actinidia deliciosa, and green malachite, respectively, were prepared in which the photoanodes were immersed to analyze the photoconversion efficiency of the assembled dye-synthesized solar cells. The power conversion efficiency of fabricated DSSCs, which was confirmed from the I-V curve, is in the range from 0.84 to 2.15%. This study confirms that mint (Mentha) dye and Nd-doped BiFeO3 materials were found to be the most efficient sensitizer and photoanode materials among all the sensitizers and photoanodes tested.

18.
Front Chem ; 11: 1299013, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38162394

RESUMEN

A change in the composition and dopant content of selective atoms in a material leads to their new desired properties by altering the structure, which can significantly improve the performance of relevant devices. By acknowledging this, we focused on characterizing the optoelectronic and structural properties of cadmium-substituted zinc selenide (Zn1-xCdxSe; 0 ≤ X ≤ 1) semiconductors using density functional theory (DFT) within the generalized gradient approximation (GGA), EV-GGA, and mBJ approximations. The results proved the cubic symmetry of the investigated materials at all Cd concentrations (0, 0.25, 0.50, 0.75, and 1). Although a linear surge in the lattice constant is observed with the change in Cd content, the bulk modulus exhibits a reverse trend. These materials are observed to be direct bandgap semiconductors at all Cd concentrations, with a decrease in electronic bandgap from 2.76 eV to 1.87 eV, and have isotropic optical properties, showing their potential applicability as a blue-to-red display. The fundamental optical properties of the materials, such as optical conductivity, reflectance, refractive index, absorption, and extinction coefficient, are also discussed. These outcomes provide a computational understanding of the diverse applications of Zn1-xCdxSe semiconductors in optoelectronic, photonic, and photovoltaic devices, particularly for a visible-range display.

19.
Nanomaterials (Basel) ; 12(17)2022 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-36080010

RESUMEN

In this study, novel hydrothermal ex situ synthesis was adopted to synthesize MoS2/WO3 heterostructures using two different molar ratios of 1:1 and 1:4. The "bottom-up" assembly was successfully developed to synthesize spherical and flaky-shaped heterostructures. Their structural, morphological, compositional, and bandgap characterizations were investigated through XRD, EDX, SEM, UV-Visible spectroscopy, and FTIR analysis. These analyses help to understand the agglomerated heterostructures of MoS2/WO3 for their possible photocatalytic application. Therefore, prepared heterostructures were tested for RhB photodegradation using solar light irradiation. The % efficiency of MoS2/WO3 composites for 30 min irradiation of 1:1 was 91.41% and for 1:4 was 98.16%. Similarly, the % efficiency of 1:1 MoS2/WO3 heterostructures for 60 min exposure was 92.68%; for 1:4, it was observed as 98.56%; and for 90 min exposure, the % efficiency of 1:1 was 92.41%, and 98.48% was calculated for 1:4 composites. The photocatalytic efficiency was further verified by reusability experiments (three cycles), and the characterization results afterward indicated the ensemble of crystalline planes that were responsible for the high efficiency. Moreover, these heterostructures showed stability over three cycles, indicating their future applications for other photocatalytic applications.

20.
Sci Rep ; 12(1): 12978, 2022 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-35902680

RESUMEN

The optoelectronic properties of the ternary Cd0.25Zn0.75Se alloy are reported under the influence of a high pressure ranging from 0 to 25 GPa, within a modified Becke-Jhonson potential using density functional theory. This alloy has a cubic symmetry, is mechanically stable, and its bulk modulus rises with pressure. It is observed to be a direct bandgap material with a bandgap energy that increases from 2.37 to 3.11 eV with rise in pressure. Pressure changes the optical and electronic properties, causing the absorption coefficient to rise and absorb visible green-to-violet light. The static dielectric constant, along with the static index of refraction, both increase under the influence of pressure. Optical constants, including dielectric constant, optical conductivity, refractive index, extinction coefficient, and reflection, are also investigated and discussed. This DFT forecast explores important research directions for the usage of the CdZnSe semiconductor alloys in the manufacturing of space photovoltaic and optoelectronic devices operating at different pressures.

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