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2 × 2 × 2 supercell structure of V-doped ZnO using WIEN2K shown in z-x plane, y-z plane, and 3D (zinc atoms: green, vanadium atoms: purple, oxygen atoms: maroon).
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In this work, microemulsion method has been followed to synthesize vanadium-doped Zn1−xVxO (with x = 0.0, 0.02, 0.04, 0.06, 0.08, and 0.10) nanoparticles. The prepared samples are characterized by several techniques to investigate the structural, morphology, electronic, functional bonding, and optical properties. X-ray diffractometer (XRD) analysis...
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... ionic radii of V 2+ are 0.79 Å, which is slightly larger than the ionic radii of Zn 2+ (0.74 Å) [33]. It is also confirmed from the ZnO wurtzite supercell structure system, as shown in Figure 2, (produce using WIEN2K software (Institute of Materials Chemistry, TU Wien, Vienna, Austria), that the Zn 2+ tetrahedral sites are being replaced by V 2+ ions. This confirms the existence of a V 2+ stabilized oxidation state after the sintering in the open air at 500 • C, which is in agreement with the literature [34,35]. ...
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... Rietveld refinements results for the V-doped ZnO have been tabulated in Table 2. The hexagonal structure is also explained by the results of Rietveld analysis, as shown in Figure 2. In general, with the increase of the weight fraction of V, the weighted profile R-factors (Rwp), the profile R-factor (Rp) and goodness of fit (GOF) show a decreasing trend, which implies the accurate pattern fitting [37,38]. ...
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... Rietveld refinements results for the V-doped ZnO have been tabulated in Table 2. The hexagonal structure is also explained by the results of Rietveld analysis, as shown in Figure 2. In general, with the increase of the weight fraction of V, the weighted profile R-factors (Rwp), the profile R-factor (Rp) and goodness of fit (GOF) show a decreasing trend, which implies the accurate pattern fitting [37,38]. ...
Citations
... For the size and morphology control, the method of synthesis could be an important parameter. Different synthesis methods were reported for synthesizing semiconductors with nanosized dimensions including, solgel [41], co-precipitation [42], mechanical milling [43], microemulsion [44], hydrothermal [45], solvothermal [46], etc. Among them, the polyacrylamide gel method is a unique approach for producing nanoparticles with the aid of a polymeric network as a template [47][48][49]. ...
In the present work, CuO/CuFe2O4 nanoparticles were synthesized via a polyacrylamide gel. The produced nanocomposites were utilized as a gas sensor for the detection of H2S gas. The nanoparticles were characterized via XRD, FTIR, SEM and TEM techniques. XRD results revealed that the as-prepared product was amorphous and CuO and CuFe2O4 phases were formed after calcination at 800°C. Microstructural studies showed that the nanoparticles have a particle size distribution ranging from 60 to 120 nm. Most of the particles had a spherical morphology. The polyacrylamide network acted as a template for the formation of the nanoparticles. The H2S gas sensing characteristics of the products were studied at different concentrations and operating temperatures. In addition, the effect of humidity on the gas-sensing response was investigated. The prepared CuO/CuFe2O4 sensors can respond up to 25 when exposed to 10 ppm H2S which is higher than the pure CuO or CuFe2O4 sensors. The sensors reached a detection limit of 0.1 ppm and demonstrated clear sensitivity and quick response and recovery behavior toward H2S gas. The CuO/CuFe2O4 heterogeneous nanostructures also showed proper H2S gas response and selectivity in response to interfering gases like NH3, NO2, HCHO and CO. The gas sensing mechanism of the composites was also discussed.
... Table 1 provides a comprehensive overview of the properties of some mixed metal/metal oxide compounds toward different categories of microorganisms. Various methods have been proposed in the literature for the synthesis of metal oxide nanostructures, including microemulsion [35], hydrothermal [1], a solid-state chemical method [36], sol-gel approach [37], and coprecipitation [38]. The utilization of nitrates as a means of obtaining metallic ions and the use of non-toxic substances as a size-controlling agent has demonstrated the effectiveness of the sol-gel technique in producing crystalline powders of high purity and low cost while also allowing for precise control over homogeneity. ...
Nanomaterials show great potential for effective antibacterial therapies by targeting multiple bacterial species and overcoming resistance mechanisms through mechanical damage to cells. This disruption occurs via interactions between nanoparticles and bacterial cell walls, leading to damage that compromises bacterial cell integrity. Such mechanisms highlight the potential of nanomaterials as valuable tools in the battle against bacterial infections. In this study, nanocomposites of Mg1-xZnxO (x = 0, 0.1, 0.2, and 0.3) were synthesized using the sol–gel technique. The structural, surface morphological, and antibacterial effects of pure MgO and MgO doped with ZnO were investigated. For structural and morphological evaluations, X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM) were used. The Rietveld refinement software analysis of XRD data revealed that the phase fraction of MgO exhibits a direct and linear relationship with increasing zinc nitrate concentration. In contrast, the ZnO phase shows an inverse correlation. It was also observed that, as the concentration of ZnO increased, the crystal sizes of the MgO and ZnO phases decreased from 35.87 to 31.29 nm and 46.16 to 41.41 nm, respectively, while their lattice constants increased. The FE-SEM images demonstrated that the particle morphologies of all the samples were similar, with no discernible distinctions. In general, the particles exhibited a small spherical appearance, and their sizes ranged from 73.771 to 76 nm, with irregular agglomeration influenced by the concentration of ZnO. In addition, the synthesized MgO/ZnO nanocomposite exhibited a synergistic antibacterial effect, inhibiting the growth of both Gram-positive Staphylococcus aureus and Gram-negative bacteria Escherichia coli. Notably, the rate of Gram-positive and Gram-negative bacterial growth inhibition increased as the concentration of ZnO in the MgO nanocomposite increased.
... Ali et al. prepared vanadium-doped ZnO nanoparticles using the microemulsion precipitation process [99]. Microemulsions were formulated by combining equal moles of zinc acetate and vanadium chloride (VCl2) and then adding the CTAB (C19H42BrN) as a stabilizing agent. ...
The wide array of structures and characteristics found in ZnO-based nanostructures offers them a versatile range of uses. Over the past decade, significant attention has been drawn to the possible applications of these materials in the biomedical field, owing to their distinctive electronic, optical, catalytic, and antimicrobial attributes, alongside their exceptional biocompatibility and surface chemistry. With environmental degradation and an aging population contributing to escalating healthcare needs and costs, particularly in developing nations, there's a growing demand for more effective and affordable biomedical devices with innovative functionalities. This review delves into particular essential facets of different synthetic approaches (chemical and green) that contribute to the production of effective multifunctional nano-ZnO particles for biomedical applications. Outlining the conjugation of ZnO nanoparticles highlights the enhancement of biomedical capacity while lowering toxicity. Additionally, recent progress in the study of ZnO-based nano-biomaterials tailored for biomedical purposes is explored, including biosensing, bioimaging, tissue regeneration, drug delivery, as well as vaccines and immunotherapy. The final section focuses on nano-ZnO par-ticles' toxicity mechanism with special emphasis to their neurotoxic potential, as well as the primary toxicity pathways, providing an overall review of the up-to-date development and future perspectives of nano-ZnO particles in the biomedicine field.
... Furthermore, using mixed nanoparticles at lower concentrations than single nanoparticles reduces toxicity, increases the inhibition effects, and may prevent nanoparticle resistance establishment [7,14]. ZnO and MgO nanoparticles are commonly employed in diverse domains such as gas sensing, photocatalysis [16], nanomedicine, and antibacterial applications [17][18][19][20][21]. Various methods have been proposed in the literature for the synthesis of metal oxide nanostructures, including microemulsion [22], hydrothermal [1], a solid-state chemical method [23], sol-gel approach [24], co-precipitation [25], and others. The utilization of nitrates as a means of obtaining metallic ions and the use of non-toxic substances as a size-controlling agent has demonstrated the effectiveness of the sol-gel technique in producing crystalline powders of high purity and low cost while also allowing for precise control over homogeneity. ...
In this study, nanocomposites of Mg 1 − x Zn x O ( x = 0, 0.1, 0.2, and 0.3) were synthesized using the sol-gel technique. The structural, surface morphological, and antibacterial effects of pure MgO and MgO doped with ZnO were investigated. For structural and morphological evaluations, X-ray diffraction (XRD) and Field emission scanning electron microscopy (FE-SEM) were used. The Rietveld refinement software analysis of XRD data revealed that the phase fraction of MgO exhibits a direct and linear relationship with increasing zinc nitrate concentration. In contrast, the ZnO phase shows an inverse correlation. It was also observed that, as the concentration of ZnO increased, the crystal sizes of the MgO and ZnO phases decreased from 35.87 to 31.29 nm and 46.16 to 41.41 nm, respectively, while their lattice constants increased. The FE-SEM images demonstrated that the particle morphologies of all the samples were similar, with no discernible distinctions. In general, the particles exhibited a small spherical appearance, and their sizes ranged from 73.771 to 76 nm, with irregular agglomeration influenced by the concentration of ZnO. In addition, the synthesized MgO/ZnO nanocomposite exhibited a synergistic antibacterial effect, inhibiting the growth of both Gram-positive Staphylococcus aureus and gram-negative bacteria Escherichia coli . Notably, the rate of Gram-positive and Gram-negative bacterial growth inhibition increased as the concentration of ZnO in the MgO nanocomposite increased.
... Zinc oxide (ZnO) is a semiconducting compound that belongs to the II-VI group and has a wide direct bandgap of ~ 3.35 eV at room temperature, exceptional chemical stability, and a high exciton binding energy (60 meV) [7][8][9]. ZnO nanoparticles are one of the most interesting materials used in many different types of devices, including electronics [10,11], photonics [12], spintronics [13], biosensors [7], drug delivery systems [14,15], photocatalysis [16,17] andbio imaging [18,19]. However, there are still some significant barriers to the creation of devices using both pure ZnO and transition metals doped ZnO [18]. ...
... ZnO nanoparticles are one of the most interesting materials used in many different types of devices, including electronics [10,11], photonics [12], spintronics [13], biosensors [7], drug delivery systems [14,15], photocatalysis [16,17] andbio imaging [18,19]. However, there are still some significant barriers to the creation of devices using both pure ZnO and transition metals doped ZnO [18]. ...
The aim of the research to elucidate the photosensitivity of a synthesized nanomaterial, i.e. ZnO NPs and 10% vanadium-doped ZnO NPs with their characterization. The material were characterized by X-Ray diffractometer (XRD), Fourier Transform Infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and Photo-luminescence (PL). XRD confirms the formation of ZnO and V-ZnO NPs from its peaks and confirmed the doping of a vanadium element with ZnO NPs by JCPDS with different calcination temperature (450 • C, 550 • C and 660 • C). By increasing a temperature its peak or crystallinity is also increases and confined its atom in a peak. FTIR confirms the formation of ZnO and V-doped ZnO NPs by their specific spectral peaks. SEM images shows that the ZnO NPs is spherical in shape with an average particle size of 50 nm and V-ZnO NPs is polyhedral or hexagonal with an average particle size of 74 nm confirms its morphology. The property of photoconductivity has been measured by photoluminescence via UV-vis illumination. Sample with high calcination show good result due to increase in Zn i defect but with vanadium-doped ZnO NPs shows the higher and more interesting result than the ZnO NPs.
... The bands at 783 cm −1 and 545 (552) cm −1 were attributed to the stretching vibrations of the V-O-V bands, respectively [42,43]. The hydroxyl group at 3410 cm −1 and the bands associated with the V-doped ZnO at 780 cm −1 and 650 cm −1 in V:ZnO obtained by the sol-gel method were previously reported [28,44]. Figure 2 shows the FTIR spectra of the V doped ZnO gels obtained by the microwave assisted sol-gel method (MW) and the classic sol-gel method (SG). ...
... In the spectra of the samples, the Zn-OH band was observed at 677 cm −1 , and the bands at 502 and 445 cm −1 were attributed to Zn-O vibration. The small band at 1123 cm −1 was characteristic of V=O absorption, as reported by Ali [28]. The bands at 783 cm −1 and 545 (552) cm −1 were attributed to the stretching vibrations of the V-O-V bands, respectively [42,43]. ...
... The bands at 783 cm −1 and 545 (552) cm −1 were attributed to the stretching vibrations of the V-O-V bands, respectively [42,43]. The hydroxyl group at 3410 cm −1 and the bands associated with the V-doped ZnO at 780 cm −1 and 650 cm −1 in V:ZnO obtained by the sol-gel method were previously reported [28,44]. ...
In this paper, we conducted a fundamental study concerning the effect of thermal treatment on the structure and morphology of 2 mol% vanadium doped ZnO nanopowders obtained by microwave assisted sol–gel method (MW). The samples were analyzed by DTA, FTIR, XRD, SEM, and UV–Vis spectroscopy. The DTA results showed that above 500 °C, there was no mass loss in the TG curves, and ZnO crystallization occurred. The XRD patterns of the thermally treated powders at 500 °C and 650 °C showed the crystallization of ZnO (zincite) belonging to the wurtzite-type structure. It was found that in the 650 °C thermally treated powder, aside from ZnO, traces of Zn3(VO4)2 existed. FTIR spectra of the annealed samples confirmed the formation of the ZnO crystalline phase and V–O bands. The micrographs revealed that the temperature influenced the morphology. The increase in the annealing temperature led to the grain growth. The SEM images of the MW powder thermally treated at 650 °C showed two types of grains: hexagonal grains and cylindrical nanorods. UV–Vis spectra showed that the absorption band also increased with the increasing temperature of thermal treatment. The MW sample annealed at 650 °C had the highest absorption in ultraviolet domain.
... The resultant particles have a narrow distribution, spanning from 2.3 to 3.9 nm [43]. Ali et al., 2019, produced well defined Vdoped ZnO nanoparticles by microemulsion, with a tunable band gap based on incorporated vanadium amount [44]. ...
Nanostructured materials formed from metal oxides offer a number of advantages, such as large surface area, improved mechanical and other physical properties, as well as adjustable electronic properties that are important in the development and application of chemical sensors and biosensor design. Nanostructures are classified using the dimensions of the nanostructure itself and their components. In this review, various types of nanostructures classified as 0D, 1D, 2D, and 3D that were successfully applied in chemical sensors and biosensors, and formed from metal oxides using different synthesis methods, are discussed. In particular, significant attention is paid to detailed analysis and future prospects of the synthesis methods of metal oxide nanostructures and their integration in chemical sensors and biosensor design.
... In addition to the above, wet chemical methods, as solgel [31] and microemulsion synthesis [32] were also employed for V-doped ZnO films preparation. In both cases films with enhanced optical properties were obtained. ...
In the present work ZnO thin films doped with Mn and V in the same amount (2 at.%) were obtained by 5 successive depositions on Pt/Ti/SiO2/Si substrates using the sol–gel and spin coating method. Their structural, morphological, chemical, optical, and piezoelectric properties were investigated by X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), X-Ray Photoelectron Spectroscopy (XPS), Spectroscopic Ellipsometry (SE) and piezoelectric characterizations. The work discusses the recent results regarding the comparative influence of Mn and V on the properties of the ZnO thin films, in view of various possible applications. For example, both types of films can be used as piezoelectric materials, but the samples containing V present higher piezoelectric coefficient than the films with Mn, having larger thickness and switchable spontaneous polarization induced by V dopants, thus an increased piezoelectric coefficient. The V-doped ZnO films are also more sensitive as gas detectors, than undoped ones, due to their increased porosity.
Comparative influence of Mn and V dopants on the morphological, chemical, optical and piezoelectric properties of sol-gel ZnO films deposited on Pt/Ti/SiO2/Si substrate
... The diminish of crystallinity and a shift in the position of the major diffraction peaks which is mainly due to the ionic radius of the V 5+ (0.88 Å) and Ag + (1.15 Å) are moderately higher than Zn 2+ (0.74 Å). The creation of crystalline vanadium and silver clusters in the nanorods is clearly indicated by the appearance of the V and Ag peaks in the diffraction patterns (Ali et al., 2019). The average crystalline size and lattice parameters of the prepared samples were computed from the major intensity peak (101) using following formulas (Solati and Dorranian, 2017;Chauhan et al., 2020). ...
In this present work, we synthesized the V-Ag co-doped ZnO nanorods for high performance supercapacitors using one step sol-gel method. The influences of the doping (V and Ag) on the morphological, structural characteristics, electrochemical performance, and long term cycle of ZnO upon redox was investigated for their applicability in SCs. The XRD results revealed to the crystallite sizes of pure ZnO, V0.03Ag0.03ZnO, V0.05Ag0.05ZnO, and V0.07Ag0.07ZnO samples were in the ranges of 32.79, 11.37, 9.30, and 8.60 nm, respectively. The HR-SEM and HR-TEM images revealed similar nanorod morphology. The appearance of Zn, Ag, V, and O was confirmed from the EDX and XPS analysis of the V0.07Ag0.07ZnO nanorods without any observation of additional peaks. The CV results validated the pseudocapacitive nature of the synthesized electrodes. The highest specific capacitance was attained for the V0.07Ag0.07ZnO electrode was recorded as 2700.19 Fg⁻¹, which is higher than ZnO (402.1 Fg⁻¹) values. The GCD curves of V0.07Ag0.07ZnO electrode demonstrated remarkable charging-discharging capabilities, with cyclic retention of 93% at 1 A/g. These excellent performances of the V0.07Ag0.07ZnO electrode material make them highly appealing to future energy conversion and storage systems.
... Up till now various strategies such as doping with certain metal/metal oxides, annealing and exposing faces with different morphologies have been investigated to introduce defects in ZnO nanostructures by chemical vapor deposition, solvothermal and hydrothermal methods [18][19][20]. Vanadium (V) incorporation gives rise to either of above defects due to slight difference in ionic radii of V (0.74 Å) and Zn (0.79 Å) replacing Zn 2+ ion by V 2+ ion [25]. The existence of oxygen vacancies leads to delocalization of electron distribution and promotion of electrons excitation which is favorably responsible for conductivity enhancement and charge transportation. ...
... Moreover, it has been also found that the intensity of peaks gradually decreases with the increase in V content. A similar trend is also observed in the literature [24][25][26][27][28]. Figure S1(a) (available online at stacks.iop.org/NANO/ 33/025502/mmedia) shows low magnification FESEM image of pure ZnO sample. ...
The development of a reliable non-enzymatic multi-analyte biosensor is remained a great challenge for biomedical and industrial applications. In this prospective, rationally designed electrode materials having voltage switchable electrocatalytic properties are highly promising. Here, we report vanadium doped ZnO engineered nanostructures (Zn1-xVxO where 0≤x≤0.1) which exhibit voltage switchable electrocatalytic properties for accurate measurements of glucose and hydrogen peroxide. Microstructures and chemical analysis show that the oxygen vacancies in the material can be tuned by controlling the stoichiometric ratios which play key role for voltage dependent measurements of different analytes. The developed Zn1-xVxO nanostructures exhibit outstanding sensing ability for binary analytes with a high selectivity, low detection limit, thermal stability and long-term stability. The Zn0.9V0.1O/glassy carbon (GC) electrode shows 3-fold increase in reproducible sensitivity for both glucose (655.24 μAmM-1cm-2) and H2O2 (13309.37 μAmM-1cm-2) as compared to the pristine ZnO/GC electrode. Moreover, the electrode also shows good response for human blood serum and commercially available samples. The results demonstrate that defect engineering is a promising route for the development of cost-effective non-enzymatic multi-analyte sensors for practical applications.
