Abstract Cerium vanadate/modified bentonite (CeVO 4 /mbt) nanocomposite with different composition percentages was synthesized through a simple one-step hydrothermal method at 180 ℃, and then its ...photocatalytic activity was evaluated by decolorizing methylene blue (MB) in an aqueous solution under light exposure. In order to increase the surface area as an important parameter in photocatalytic processes, bentonite was modified by ball mill method. The structural and optical properties of the synthesized composites were determined by XRD, FT-IR, DRS, FESEM, EDS, and BET measurements. XRD and EDS results confirmed the successful synthesis of pure CeVO 4 . FESEM images and EDS mapping showed a proper distribution of rice-like CeVO 4 nanoparticles on bentonite. The removal efficiency of MB with only 0.1 g of CeVO 4 /mbt nanocomposite in 15 min was about 99%, which is significant compared to neat bentonite and pure CeVO 4 with efficiency of 30% and 57%. The mentioned nanocomposite followed the first-order kinetics, had a reaction rate constant equal to 0.1483 min –1 , and showed acceptable stability in five consecutive cycles.
Nanoscale ZnO is one of the best choices for ultraviolet (UV) protection, not only because of its antimicrobial properties but also due to its potential application for UV preservation. However, the ...behavior of nanostructured thin ZnO films and long-term effects of UV-radiation exposure have not been studied yet. In this study, we investigated the UV-protection ability of sol gel-derived thin ZnO films after different exposure times. Scanning electron microscopy, atomic force microscopy, and UV-visible optical spectroscopy were carried out to study the structure and optical properties of the ZnO films as a function of the UV-irradiation time. The results obtained showed that the prepared thin ZnO films were somewhat transparent under the visible wavelength region and protective against UV radiation. The UV-protection factor was 50+ for the prepared samples, indicating that they were excellent UV protectors. The deposited thin ZnO films demonstrated promising antibacterial potential and significant light absorbance in the UV range. The experimental results suggest that the synthesized samples have potential for applications in the health care field.
Plants are one of the best sources to obtain a variety of natural surfactants in the field of green synthesizing material. Sambucus ebulus, which has unique natural properties, has been considered a ...promising material in traditional Asian medicine. In this context, zinc oxide nanoparticles (ZnO NPs) were prepared using S. ebulus leaf extract, and their physicochemical properties were investigated. X-ray diffraction (XRD) results revealed that the prepared ZnO NPs are highly crystalline, having a wurtzite crystal structure. The average crystallite size of prepared NPs was around 17 nm. Green synthesized NPs showed excellent absorption in the UV region as well as strong yellow-orange emission at room temperature. Prepared nanoparticles exhibited good antibacterial activity against various organisms and a passable photocatalytic degradation of methylene blue dye pollutants. The obtained results demonstrated that the biosynthesized ZnO NPs reveal interesting characteristics for various potential applications in the future.
Structural, morphological, optical, and luminescence properties of pure CdWO
4
, Ag
+
-doped CdWO
4
, and Gd
3+
-doped CdWO
4
(CWO, CWO: Ag, & CWO: Gd) nanopowders successfully synthesized by the ...low-cost co-precipitation method at room temperature were investigated using X-ray diffraction (XRD), EDX elemental mapping, Fourier transform infrared spectrometer (FTIR), UV–Vis absorbance spectroscopy, transmission electron microscopy (TEM), photoluminescence spectroscopy (PL), and ion-beam-induced luminescence (IBIL) measurements. XRD patterns of all samples confirmed the formation of the polycrystalline monophasic wolframite CdWO4. Parameters of the unit cells also were characterized by the Rietveld analysis. TEM images showed that the mean size of particles was 62 nm, 68 nm, and 53 nm for CWO, CWO: 0.5at%Ag
+
, and CWO: 0.5%Gd
3+
, respectively. The optical bandgap of the CWO nanoparticles was engineered by introducing Ag and Gd dopants over a range of
∼
5.3–5.57 eV. The PL and IBIL spectra of the three samples exhibited brilliant broad blue-green peaks around 468nm and 495 nm at room temperature, respectively. This research has excellently and exclusively devoted a great deal of effort to detail the simple methods of ionoluminescence and photo extraction for optical application. Ag
+
dopant indicated an excellent brilliant enhancement in emission intensity due to the probably produced shallow levels in CWO bandgap structure. Therefore simple synthesized CWO: Ag nanoparticles have potential application in photonics and solid-state luminescence materials.
Graphical abstract
The rapid emergence of intelligent textile-based sensors has sparked considerable interest within the scientific community. A pivotal factor in advancing these sensors is the development of ...semiconductors with tailored band energy levels to enhance their optical properties. This enhancement primarily arises from efficient carrier separation and interfacial charge transfer processes. In pursuit of these objectives, our study presents a novel approach to fabricate flexible thin films composed of mixed oxides, specifically zinc oxide and cadmium tungstate (ZnO/CWO), within a chitosan (CS) matrix, utilizing a cost-effective method. We conducted a comprehensive characterization of the fabricated samples, encompassing structural, morphological, and optical analyses. Techniques such as X-ray diffraction (XRD), Raman spectroscopy, field-emission scanning electron microscopy (FESEM), iono/photoluminescence, and scintillation strategies were employed. The findings from XRD and Raman spectroscopy unequivocally confirm the presence of hexagonal ZnO and monoclinic CdWO
4
structures within the thin film. Notably, the ZnO/CWO composite thin films exhibit robust emissions in the blue-green and orange spectral regions compared to pure CS at room temperature. This phenomenon occurs following excitation by a 290 nm wavelength light source and a proton beam serving as an ionizing radiation source. Furthermore, FESEM/TEM analysis reveals that the synthesized ZnO/CWO composite nanoparticles predominantly exhibit a diverse range of shapes, including cubic, rod-like, and spherical, with an average diameter size of approximately 20–80 nm, demonstrating excellent dispersion within the chitosan matrix. The results obtained in this study suggest that the prepared flexible composite film holds significant promise for future applications in adaptable optical devices.
Nowadays, the antimicrobial properties of herbal essential oils (EO) have received extensive attention due to their considerable antimicrobial potential against multidrug-resistant pathogens. ...However, the volatility and sensitivity of OEs limit their traditional use in aquatic environments. Specialized nanocarriers as additives can improve their chemical stability and solubility, delay degradation and curb rapid evaporation. With this aim, chitosan Ferula gummosa EO-nanocomposite (CS-FEO) was prepared through a facile method. In addition, the antibacterial properties were studied by observing the inhibition zone against Escherichia coli, Staphylococcus aureus, and Bacillus cereus using the agar well diffusion assay method. Further, a transparent and flexible CS-FEO biopolymer film was prepared and characterized. The results showed significant antibacterial activity of the prepared CS-FEO nanocomposite. The fabricated CS-FEO nanocomposite was characterized by Fourier transform infrared spectroscopy (FTIR), field-emission scanning electron microscopy (FESEM), and X-ray diffraction (XRD) techniques. The FTIR results revealed the interaction between chitosan and FEO, and the XRD pattern for pure CS nanoparticles indicated a high degree of crystallinity. In contrast, CS-FEO nanoparticles exhibited a reduction in crystallinity peaks, indicating that the loading of CS may further reduce its crystallinity. The obtained results demonstrates that the prepared CS-FEO nanocomposite could be a potential candidate for food and biomedical applications as they hold the promising capability of proper interactions and advanced features.
In this research, novel zinc oxide/cadmium tungstate (ZnO/CWO) nanocomposite was prepared by a simple chemical method. The prepared nanocomposite was characterized for its structural and optical ...properties by different techniques. For the first time, the radiation response of prepared nanocomposite was studied using 241Am alpha source and ion beam induced luminescence (IBIL) measurement. Also, photocurrent transient responses of the prepared nanocomposite were recorded under Xe source radiation. ZnO/CWO nanocomposite exhibited strong light emission in the blue-green range at room temperature. Under alpha irradiation, the ZnO/CWO nanocomposite showed an excellent sensitivity when compared to pure ZnO or CWO. FESEM and TEM images showed a uniform distribution of spherical nanoparticles with an average particle size of 77 nm. XRD, XPS, and EDX results indicated characteristic peaks of ZnO, CWO, and related elements in the composite. Fourier transform infrared spectroscopy confirmed the presence of several groups in the nanocomposite. Investigations indicated that the optical quality of the ZnO/CWO nanocomposite was improved when compared with pure ZnO and CWO. According to obtained results, it is anticipated that ZnO/CWO nanocomposite would hold suitable potential for applications in optoelectronic devices and detection.
•ZnO/CWO nanocomposite was prepared successfully via a simple method.•Prepared nanocomposite exhibited strong UV-blue emission peak at room temperature.•Facile prepared ZnO/CWO composite showed excellent optical response against UV, ion beam and alpha radiation for photonics applications.•It is the first report of high sensitivity and strong luminescence peak using alpha ray radiation and IBIL technique for prepared ZnO/CWO nanocomposite at room temperature.
The bioavailability, solubility, stability, and evaporation rate of essential oils can all be improved by using appropriate nanocarriers. This study describes the simple biosynthesize, ...physicochemical, optical, and biological activity of Chitosan-Ferula gummosa essential oil (CS-FEO) nanocomposite. The prepared nanocomposite was evaluated by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX) mapping, transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), UV–vis and photoluminescence (PL) techniques. The XRD investigation showed that crystallinity indexes of CS-FEO nanocomposite were lower than that of the pure CS and higher than nano-CS. According to SEM/TEM images, a spherical shape with a particle size distribution of around 50–250 nm for nanocomposite was obtained. PL measurement exhibited the addition of FEO caused a strong red emission. GC–MS analysis showed 40 various components in FEO. The antibacterial activity was studied using broth micro-dilution, disc diffusion, colony counts, and well agar diffusion methods against Gram-positive and Gram-negative bacteria. The results revealed that CS-FEO has stronger antibacterial activities than pure CS. It was also observed that the combined use of CS with FEO resulted in synergistic effects against studied bacteria. Obtained results imply that the CS-FEO may provide a new outlook in biomedical applications.
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•Ferula gummosa EO was loaded into chitosan by a simple route.•The synthesized composite nanoparticles were spherical shapes with a size of around 50-250 nm.•The antibacterial activity of CS-FEO nanocomposite improved compared to pure CS by around 30%.•This is the first report of modifying polysaccharides using FEO to emit red color under UV irradiation.
Ag+, Gd+3-doped CdWO4 (co-doped CWO) phosphor nanopowders were synthesized by an eco-friendly method and then embedded into the polymer matrix to produce a flexible and transparent thin film. A novel ...phosphor for the excitation by an ultraviolet source, 980 nm diode laser, and proton radiation was reported at room temperature and crystal structure, luminescent properties, and energy transfer between Ag+ and Gd+3 ions were thoroughly investigated. Elemental composition and chemical state analyses were measured using X-ray photoelectron spectroscopy and energy dispersive X-ray spectroscopy studies. Crystal structure and phase identification were confirmed using powder X-ray diffraction measurement. Based on all results, the flexible phosphor film prepared has good thermal stability and efficient blue-green emission under UV light, laser, and proton excitation used in emissive displays applications.
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•Ag+, Gd3-codoped CdWO4 phosphors were synthesized successfully.•A transparent flexible luminescent composite based on co-doped CWO phosphors was obtained.•The prepared composite exhibited brilliant narrow-band visible tunable emission.
In the fields of science and engineering, photoluminescent fibers have been employed for a variety of purposes, including optical storage, biological labeling, noninvasive imaging, solid-state ...lasers, light-emitting diodes, spectrum modifiers, and temperature sensors. Here, polyvinyl alcohol (PVA)-based microfibers comprising nanoparticles were fabricated via a simple stretching method as a highly luminescent and flexible material. The structural and optical features of the prepared microfibers were investigated using X-ray Diffraction (XRD), field emission scanning emission microscopy (FESEM) image and ion beam induced luminescence (IBIL) techniques. Utilizing XRD analysis, related tetragonal phase of Bi2WO6 and polymer based PVA peaks were found in the prepared microfibers. Prepared Bi2WO6 microfiber exhibited strong blue-green emission upon excitation of 2.2 MeV proton beam and under a UV lamp at room temperature. Furthermore, microfiber diameter was obtained in the range of 8-33 m. This highly luminescent microfiber is believed to be a good candidate for optical sensor and wearable optoelectronic applications.
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