Effect Of Zn Doping Research Articles

Physical and enhanced photocatalytic MO dye degradation behaviour of Zn doped β-Ga2O3 microrods

This work explored the effects of Zn doping on the structural, micrographic, optical and photocatalytic behaviour of gallium oxide (β-Ga2O3) microrods. The X-ray diffractogram (XRD) and Raman spectral analyses confirmed the monoclinic structure of β-Ga2O3, with a shift to lower angles in the XRD pattern indicating Zn incorporation into the Ga2O3 lattice. The Scanning electron microscopy (SEM) images revealed a rod-like shape, with the diameter decreasing from 604 nm to 573 nm with Zn doping. Further analysis using TEM, HR-TEM, SAED, EDX, and elemental mapping confirmed the shape, crystallinity, crystal structure, and elemental distribution. The interplanar spacings were measured as 0.4 and 0.2 nm, corresponding to the (002) and (−311) planes of β-Ga2O3. UV–Vis diffuse reflectance spectroscopy (UV–Vis DRS) showed a slight shift in the absorption edge, while photoluminescence (PL) analysis demonstrated strong UV and weak visible light emission. Photocatalytic results revealed a high efficiency of dye degradation,(i.e) 98 % (20 ppm) and 89 % (30 ppm) against methyl orange (MO) dye aqueous solution over 150 min, with a rate constant of 0.02/min and 0.01/min, respectively for 1.5 wt% Zn doping. This suggests that the Zn-doped material holds promise as a photocatalyst for wastewater treatment applications.

Unravelling the effects of Zn doping on the physical properties of Co3O4 thin films: experimental study and numerical simulation based on the AZO/ZnS/Co3O4:Zn/Mo/SLG solar cells

Unravelling the effects of Zn doping on the physical properties of Co3O4 thin films: experimental study and numerical simulation based on the AZO/ZnS/Co3O4:Zn/Mo/SLG solar cells

The effect of Zn-doping on electrical properties, hydration, sintering and chemical resistance of hexagonal perovskite Ba7In6Al2O19

A CO2-stable, easily sintered proton-conducting oxide electrolytes based on solid solution Ba7In6Al2–xZnxO19-0.5x with hexagonal structure has been synthesized for the first time. Within the homogeneity region (0 ≤ x ≤ 0.10), there is an increase in unit cell parameters, cell volumes and free cell volumes. The addition of Zn2+ markedly improved the sinterability of the material. The relative density of the ceramics of the doped samples reached 95 % at lower sintering temperatures than the parent phase. The electrical conductivity was studied using electrochemical impedance spectroscopy. Upon doping the oxygen-ion conductivity increased by 0.25 orders of magnitude at 800 °C. Proton transport was predominant below 500 °C for a wet atmosphere (pH2O = 1.92·10−2 atm). The investigated phases Ba7In6Al2–xZnxO19-0.5x are capable of hydration and incorporate up to 1.45 mol H2O vs 0.41 mol H2O for the parent phase. The studied phases exhibit chemical resistance to CO2 under heat treatment at 600 °C. It was shown that solid solution Ba7In6Al2–xZnxO19-0.5x is a promising electrolyte material for intermediate-temperature fuel cells.

The effect of Zn doping on the structure, phase transformation and electric properties of 0.5BZT-0.5BCT materials

In the current study, an improved method of adding Zn ion doping to the 0.5BZT–0.5BCT–based films with high pyroelectric properties was designed. Under different Zn ion doping ratios, the structure, dielectric constant, phase transition relationship and other characteristics of the test product were analyzed experimentally to obtain the optimal ratio parameters. The experimental results demonstrate that the dielectric properties of the 0.5BZT–0.5BCT–xZn–based films proposed in this study can be far superior to those of other films under the optimal preparation process. The optimal dielectric properties and ferroelectric properties are obtained when the doped data are 0.008. Considering the comprehensive dielectric and energy storage capacity, the optimal doping ratio is 0.01, which can take into account dielectric data and energy storage performance. The energy storage density is 1.842 J/cm3, and the energy storage efficiency exceeds 30%. From 0 to 0.02, the properties of the material, such as the hysteresis loop and phase transition relationship are excellent. The properties of the materials studied in this study are excellent, and they are excellent candidate materials for the future application of ferroelectric materials, and provide ideas for related work.

Facile Synthesis and Electrochemical Analysis of Zn-Doped V2O5 Anode Materials for High-Rate Li Storage

The surging demand for Li rechargeable batteries with high energy densities and rapid rate capability has propelled research on materials that can replace the conventional anode materials like graphite. Vanadium pentoxides (V2O5) have emerged as promising anode candidates owing to their excellent rate capability. Specifically, V2O5 allows the electrochemical prelithiation process, in which three Li-ions can be inserted to form Li3V2O5, followed by reversible insertion and extraction of two Li-ions. Nevertheless, the unsatisfactory Li-ion diffusion coefficients and electrical conductivities of these materials remain major drawbacks. Here, we propose a Zn-doped V2O5 anode, fabricated using a two-step sol–gel method, for high-rate Li-ion batteries. Zn was incorporated into V2O5 to enhance the Li-ion transport kinetics through the electrode. The crystal structure (orthorhombic) of Zn-doped V2O5 was identified by X-ray diffraction analysis, and the Zn doping was confirmed by X-ray photoelectron microscopy. The effect of Zn doping was thoroughly examined using various analytical methods, such as cyclic voltammetry and galvanostatic intermittent titration technique. The Zn-doped V2O5 electrode exhibited remarkable cycling durability, enduring for 1000 cycles, while retaining an enhanced capacity, even under a high rate of 2C.

Investigating the effect of Zn doping and temperature on the photoluminescence behaviour of CuLaSe2 quantum dots.

In this study, CuLaSe2 and ZnCuLaSe2 quantum dots (QDs) with a mean size of ~4nm were synthesized and characterized, and their temperature-dependent photoluminescence (PL) properties were studied in the temperature range from 90 to 300 K for the first time. The results show that the obtained QDs were spherical and revealed excitonic band gaps. The PL intensity for both types of materials decreased when increasing the temperature to 300 K, which was attributed to the nonradiative relaxation and thermal escape mechanisms. As the temperature was increased, the PL linewidths broadened, and PL peak energies were red shifted for both types of QDs due to the exciton-phonon coupling and lattice deformation potential mechanisms. In addition, we found that as the temperature was decreased, the PL spectrum of ZnCuLaSe2 QDs contained two extra components, which could be attributed to the shallow defect sites (low energy peak) and the crystal phase transition process (high energy peak). The spectrum of CuLaSe2 QDs contained one extra component, which could be attributed to the crystal phase transition process.

Inherent and induced defects in mixed-phase CuO nanoparticles

Copper (Cupric) oxide is a readily synthesized, non-toxic metal oxide with a wide range of uses, including the treatment of water, the manufacture of electronic devices, solar cells, cathodes for lithium-ion primary batteries, gas sensors, electrochromic devices, supercapacitors, and field effect transistors. The effects of Zn doping in CuO in three different concentrations (weights %) were investigated. The band gap and carrier concentration were altered due to the formation of defect energy states, lattice stresses, and the formation of ZnO, and Cu2O in addition to CuO. Temperature increases from room temperature resulted in the production of metal oxides with preferred crystal growth in specific orientations. An increase in temperature, from 300 °C to 500 °C, generated residual strain release and atomic diffusions, resulting in grain growth and a reduction in the band gap. The changes in UV and PL spectra predicted the growth kinetics involved

Nanopolyhedral Zn/Fe-NC derived from bimetallic zeolitic imidazole frameworks as an efficient catalyst for the oxygen reduction reaction in an air-cathode microbial fuel cell

The synergistic effect of Zn, N and moderate Fe doping enhances the ORR performance. The maximum power density of the Zn/Fe-NC-0.5 MFC is 1954 ± 20 mW m−2.

Design of porous ZrO2 with well-tuned band structures and strong visible-light harvesting via Zn doping for enhanced visible-light photocatalysis

As one of huge-gap semiconductors, zirconium dioxide (ZrO2) has been emerging as one of popular photocatalysts for treating wastewater, and the band gap engineering of ZrO2 for efficient visible-light harvesting and high-performance photocatalysis is probably the most important challenge. In this work, porous Zn doped Zr3+-ZrO2 nanostructures with strong visible-light harvesting capacity were fabricated via a calcination process for tetracycline degradation. The obtained (Zn, Zr3+)-ZrO2 samples showed greatly narrowed band gaps and enhanced visible-light harvesting capacity. In addition, the photocatalytic performance of the (Zn, Zr3+)-ZrO2 nanostructures was studied with tetracycline degradation as a model reaction. Among these prepared samples, the optimal (Zn, Zr3+)-ZrO2-5% sample exhibited remarkably improved tetracycline degradation visible-light irradiation, and the apparent rate constant reached 0.04958 min−1, which was 7.05 times of pristine Zr3+-ZrO2. The boosted photocatalytic performance of the (Zn, Zr3+)-ZrO2 nanostructures were mainly ascribed to Zn doping effects as along as the high surface areas. Finally, possible photocatalytic mechanism, degradation pathways, and toxicity assessment were also studied. Current results indicate the significant roles of Zn doping in regulation of band gaps and morphology control of ZrO2 for high-performance photocatalytic applications.

Effect of Zn doping on the structure and electrical conductivity of Mn1.5Co1.5O4 spinel

Electrical conductivity is one of the most important concerns in spinel-structured antioxidant films coated on a solid oxide fuel cell separator, and the mechanism of electrical conduction involves the small polaron hopping through corner-shared octahedral sites. Arranging favorable ions in the octahedral sites rather than in the tetrahedral sites is better for achieving higher electrical conduction. In this study, Zn, which prefers the tetrahedral site, was substituted for the Mn1.5Co1.5O4 spinel to arrange site distribution. The crystal structure, electrical conductivity, and thermal expansion behavior of Zn-substituted ZMCOs [ZnxMn1.5−0.5xCo1.5−0.5xO4 (0.0 ≤ x ≤ 0.6)] were investigated. At Zn = 0.2, the highest electrical conductivity of 42.1 S/cm was observed, while at Zn > 0.2, the electrical conductivity decreased due to decreased Co2+/CoIII and Mn3+/Mn4+ pair concentration because Zn ions started to occupy the octahedral site. The higher the Zn concentration of ZMCO, the lower the distortion of the MnO6 octahedron via the Jahn–Teller effect, resulting in a higher symmetry of the crystal structure. Therefore, with the increase in the Zn concentration, a mixture of tetragonal-cubic phase changed to cubic phase. In addition, the phase transition temperature of the tetragonal-cubic phase decreased.

The electrical characteristics and conduction mechanisms of Zn doped silicon-based Schottky barrier diode

In this study, we investigated the effects of Zn doping on electrical properties and conduction mechanisms of n-silicon (n-Si) diodes using current-voltage (I–V) and capacitance-voltage-frequency (C–V–f) measurements. The results revealed that Zn doping alters the I–V behaviour of the diode from a typical exponential curve to an ohmic one. Notably, Zn doping increased the reverse current by a factor of 37, while reducing the forward current by a factor of 3 at 3 V. This suggested that Zn-related defects introduced more minority carriers into the Si. The introduction of minority carriers is confirmed by a change in material conductivity-type from n-to p-type. Moreover, Zn doping reduces the full depletion voltage (FDV), meaning the diode could be fully depleted with a lower voltage. This reduction in FDV was crucial for designing highly sensitive radiation detectors. The observed changes in the diode's electrical behaviour were attributed to defects introduced by Zn into Si. Zn-doped n-Si diodes exhibited characteristics akin to radiation-resistant diodes. These findings implied that Zn may be instrumental in advancing research focused on enhancing silicon properties and developing radiation-resistant detectors for high-energy physics studies.

The effect of Zn doping on the optical properties and conductivity of SnS thin film formed by chemical bath deposition

The effect of Zn doping on the optical properties and conductivity of SnS thin film formed by chemical bath deposition

Optical characterizations of lightly doped (PbS)1−x Znx thin films influenced by film thickness and annealing temperature for applications in highly intensive radiation systems

The lightly Zn-doped (PbS)1−x (Zn)x thin films were synthesized by the thermal deposition technique. The structure, morphology, and elemental analyses were carried out by XRD, SEM, and EDS, respectively, and characterised by UV–VIS–NIR spectroscopy. The optical absorption, transmission, and reflection have been studied and analysed. The linear and non-linear parameters have been determined, explained, and compared with the reported results. The effects of Zn-doping, film thickness, and annealing temperature on NLO-parameters have been considered. The better 2.78 × 10–10 and 2.93 × 10–10 esu values of the non-linear refractive index n2 and 3rd-order optical polarizability χ(3), respectively, were attained by (PbS)0.97 (Zn)0.03 film of 150 nm thick annealed at 200 °C.

Effect of Zn Doping on Antibacterial Efficacy of CuO Nanostructures

AbstractBacterial diseases are causing major health issues across the world. Recent research has revealed that the metal ion discharge of nanomaterials is extremely effective at eradicating bacterial outbreaks and resistance. Reactive oxygen species (ROS) for antibacterial functions have been produced using nanomaterials with high specific surface area, complex structural framework, and spectral properties. In this study, we thoroughly investigated the impact of Zn dopants on copper oxide (CuO) nanostructures and their nanomaterial‐based antibacterial processes. The method of production includes the formation of CuO and Zn‐doped CuO nanostructures via chemical coprecipitation. By using several characterization techniques, the as‐synthesized nanostructures were confirmed. Based on their specific surface area and surface‐active site, the different antibacterial activities of these dopants vary the antibacterial action. The antibacterial activity was evaluated using the agar well diffusion method. A significant antibacterial action was observed in the samples. In the pharmaceutical and food sectors, this CuO and its combined dopants can be a substitute for synthetic antibacterial agents.

Effect of (Co and Zn) doping on structural, characterization and the heavy metal removal efficiency of CuFe2O4 nanoparticles

Nanomaterials, especially ferrites, have various applications in mechanical, electrical, and optical fields. However, their abilities in environmental applications remain unexplored. In this work, the flash auto-combustion method has been used to prepare three different compositions of CuFe2O4, Zn-CuFe2O4, and Co-CuFe2O4 nanocomposite. The structure, spectroscopic, surface, and morphological properties of the prepared samples were characterized using XRD, FTIR, BET, and HRTEM, respectively. According to XRD analysis, the prepared ferrites consist of nanocrystalline particles with sizes of 24.5, 37.5, and 32.6 for CuFe2O4, Zn-CuFe2O4, and Co-CuFe2O4, respectively. Zn-CuFe2O4 and Co-CuFe2O4 had a single cubic phase, while a tetragonal phase was formed in CuFe2O4. The addition of cobalt and zinc to copper ferrite increased the crystallite size and the lattice parameters. The absorption band in FTIR spectra, which represents the stretching vibrations along the [MetalO] bond at the octahedral (B) position, was nearly constant (412 Cm−1) by the addition of Zn to CuFe2O4. The surface area and quantity of gas adsorbed on the surface of Co-CuFe2O4 were the highest. The greatest force constants [(Ko = 1.37 & KT = 1.32 105 dyne/cm] were detected in Zn-CuFe2O4. Co-CuFe2O4 exhibited the highest saturation magnetization as well as magnetocrystalline anisotropy. From FESM, the particles have a homogeneous distribution, which is confirmed by the appropriate synthesis method. The nanonanosamples had an average particle size of 79 nm, 66 nm, and 56 nm for CuFe2O4, Co-CuFe2O4, and Zn-CuFe2O4, respectively. The surface area and quantity of gas adsorbed on the sample surface were increased by doping Cu ferrite with Co and Zn. All the prepared samples were tested for heavy metal (Cr6+) removal from the water; they demonstrated promising results after optimizing the experimental conditions at pH 7 and contact time 50 min, and these values reached 54%, 90%, and 93% for CuFe2O4, Zn-CuFe2O4, and Co-CuFe2O4 nanocomposite, respectively.

Effect of Zn doping on Sr3Fe2O7-δ Ruddlesden-Popper oxides as active and robust cathodes for protonic ceramic fuel cells

Perovskite oxides are promising electrodes for protonic ceramic fuel cells (PCFCs) due to their good electrochemical performance and stability. However, the lower operating temperature results in a large polarization resistance and sluggish oxygen reduction reaction (ORR) in cathodes. Herein, Ruddlesden-Popper (R–P) type perovskite Sr3Fe2-xZnxO7-δ (SFZx, x = 0, 0.1, 0.5) were successfully synthesized and the partial replacement of Fe by Zn in SFZx demonstrates a superior ORR activity. At 750 °C, the polarization resistance of SFZ05 is 0.072 Ω cm−2, which is 47% lower than that of the undoped Sr3Fe2O7-δ (SFO), and the peak power density of the single-cell with an SFZ05 cathode reaches 523.56 mW cm−2. The distribution of relaxation time (DRT) results manifest that the rate-limiting steps of ORR are charge transfer and ionic migration processes. Furthermore, SFZ05 also presented better CO2 tolerance. These results show that SFZ05 is a promising cathode candidate with high activity and stability for PCFCs.

A Comparative Study of Electronic, Optical, and Thermoelectric Properties of Zn-Doped Bulk and Monolayer SnSe Using Ab Initio Calculations.

In this study, we explore the effects of Zn doping on the electronic, optical, and thermoelectric properties of α-SnSe in bulk and monolayer forms, employing density functional theory calculations. By varying the doping concentrations, we aim to understand the characteristics of Zn-doped SnSe in both systems. Our analysis of the electronic band structure using (PBE), (SCAN), and (HSE06) functionals reveals that all doped systems exhibit semiconductor-like behavior, making them suitable for applications in optoelectronics and photovoltaics. Notably, the conduction bands in SnSe monolayers undergo changes depending on the Zn concentration. Furthermore, the optical analysis indicates a decrease in the dielectric constant when transitioning from bulk to monolayer forms, which is advantageous for capacitor production. Moreover, heavily doped SnSe monolayers hold promise for deep ultraviolet applications. Examining the thermoelectric transport properties, we observe that Zn doping enhances the electrical conductivity in bulk SnSe at temperatures below 500 K. However, the electronic thermal conductivity of monolayer samples is lower compared to bulk samples, and it decreases consistently with increasing Zn concentrations. Additionally, the Zn-doped 2D samples exhibit high Seebeck coefficients across most of the temperature ranges investigated.

XPS and NEXAFS Studies of Zn-Doped Bismuth Iron Tantalate Pyrochlore

The effect of Zn-doping on the phase composition and optical properties of the Bi2ZnxFe1-xTa2O9.5-Δ (x = 0.3, 0.5, 0.7) was studied. XRD data showed that the samples crystallize in the structural type of pyrochlore (sp. gr.Fd-3m). For all the samples, an admixture of bismuth orthotantalate β-BiTaO4 triclinic modification up to 22.5 wt.% is observed. The content of β-BiTaO4 increases with zinc doping. The unit cell parameter of the pyrochlore phase rises from 10.4878 (x = 0.3) to 10.5154 Å (x = 0.7). The samples are characterized by a porous microstructure with indistinct grain boundaries. Zinc oxide has a sintering effect on ceramics. The charge state of the ions in Bi2ZnxFe1-xTa2O9.5-Δ was investigated by X-ray spectroscopy. NEXAFS and XPS data show that zinc doping does not change the oxidation degree of iron and bismuth ions in pyrochlore. The ions are in the charge states Bi(+3), Fe(+3), Zn(+2). In the Ta4fspectrum, an energy shift of the absorption band towards lower energies by ΔE = 0.5 eV is observed, which is typical for tantalum ions with an effective charge of (+5-δ). With the increase of x(Zn), the Bi 4f7/2 and Bi 4f5/2 bands are observed to shift to lower energies due to the distribution of some Zn(II) ions in the bismuth position.

Effect of (Al, Zn, Cu, and Sr) doping on structural, optical and electrical properties of sprayed SnO2 thin films

Tin dioxide thin films deposited onto a glass substrate were prepared by spray pyrolysis technique, and then doped with different elements which are: Al, Zn, Cu, and Sr by electroplating method, these elements were chosen for their different atomic radii. XRD illustrate that all the films were polycrystalline with a tetragonal rutile structure and a strong preferred orientation of (200) plane. Uv-vis spectrophotometer specters showed that the highest average transmittance of Al/SnO2 film was about 86.77% in the visible region and the Sr/SnO2 film had the highest band gap of 3.95 eV. From the MEB images, the morphological characteristics improved when the SnO2 thin films doped with Al and Zn but the opposite happened when it doped with Cu and Sr. The four-point probe showed that the best sample was for Al/SnO2 because it had the highest electrical conductivity around 692.306 (Ω.cm) -1.

Zn and Ni doping effect on barium hexaferrite ferroelectric, optical properties and photocatalytic activity under visible light irradiation

In this study, we explored the potential photocatalytic activity of doped ferrites by examining the effects of zinc and nickel doping on barium hexaferrite (Ba1-xZnxFe12-yNiyO19) nanoparticles. To prepare the samples, we utilized a micro-emulsion approach and evaluated the influence of dopants on their structural, ferroelectric, and photocatalytic properties. The X-ray diffraction and Raman spectra indicated that the synthesized samples were hexagonal and belonged to the P63/mmc space group. The average crystallite size has been calculated in the range of 64–67 nm. By enhancing the dopant concentration, the optical bandgap decreased from 2.19 (eV) to 1.48 (eV). The material with a narrow bandgap is useful for catalytic application and PL signal was also revealed low-rate recombination of e−-h+ pair. Moreover, photo-degradation experiment was carried out by degrading the methyl violet dye under visible light irradiation. The highly substituted material furnished 87% of dye removal, which was 56% in case of undoped sample. The Ba1-xZnxFe12-yNiyO19 material demonstrates great potential as a photocatalyst for the degradation of dyes in effluents when exposed to visible light. This finding suggests that this material could be a valuable solution for addressing the challenges posed by dye contamination in wastewater.