Properties Of Zn Research Articles

Influence of the Zn2+ concentration on the defect structure and optical properties in Zn:Fe:Cu:LiNbO3 crystals

Influence of the Zn2+ concentration on the defect structure and optical properties in Zn:Fe:Cu:LiNbO3 crystals

Mass and strain field mediated low thermal conductivity for enhanced thermoelectric properties in Zn substituted SnS

Tin Sulfide (SnS) is widely recognized as a promising material for thermoelectrics owing to its layered structure, anharmonicity, earth abundance, and minimal toxicity. This study focuses on controlling the hole...

An efficient electrolyte additive of 1,3,6-hexanetricarbonitrile for high performance aqueous zinc-ion batteries

The growth of Zn dendrites and parasitic side reactions between electrode and electrolyte are major obstacles to the development of rechargeable aqueous zinc-ion batteries. To address these critical issues, the use of nitrile organic compounds as electrolyte additives holds great promise. Herein, for the first time, we prepared a small volume concentration (x) of 1,3,6-Hexanetricarbonitrile (HTCN-x) as additives into zinc trifluoromethanesulphonate (Zn(OTF)2) electrolyte and studied their electrochemical properties in Zn||ZnxV2O5·nH2O (Zn||ZVO) cells. It was found that the strong interaction between H2O and HTCN could significantly reduce the population of solvated H2O outside the solvation sheath, leading to reduced side reactions in the aqueous Zn(OTF)2 electrolyte. Moreover, the HTCN additive also facilitates the formation of strong and stable solid electrolyte interphase (SEI) film on the surface of the Zn anode, which effectively prevents the growth of Zn dendrites and the anode corrosion caused by the electrolyte. As a result, the HTCN-x (x = 0.3) electrolyte enabled the symmetrical Zn||Zn cell to cycle over 950 h at a current of 1 mA cm−2 with a limited capacity of 1 mAh cm−2. When the HTCN-0.3 electrolyte was used in Zn||ZVO cell, the cell delivered a high initial capacity of 355.6 mAh g−1 at 0.1 A g−1 and maintained a high capacity of 330.0 mAh g−1 at 1 A g−1 after 465 cycles.

Role of deposition temperature on non-linear optical properties of spray-coated Zn0.95Nd0.05O films

The influence of deposition temperature on the structure and optical (linear and nonlinear) properties of Zn0.95Nd0.05O thin films grown on glass substrates by using the spray pyrolysis method is studied. The X-ray diffraction spectra reveal the hexagonal wurtzite structure with a reduction in peak intensity as deposition temperature increases. With increasing temperature, the prominent peak intensity changes, and the dislocation density increases. Concomitantly, the surface morphology transitions from a nanoflake to a needle-like structure. With increasing deposition temperature, the optical transmittance of the films in the visible region improves, while the energy bandgap, refractive index and extinction coefficient values decrease. The reduction of refractive index and extinction coefficient values is ascribed to decreased scattering and uniformity of the films. Further, the films exhibit saturable absorption and films deposited at 300 ℃ show a maximum for third-order nonlinear susceptibility, which is quite appealing for nonlinear optical devices and components.

Influence of K/Mg co-doping in tuning room temperature d0 ferromagnetism, optical and transport properties of ZnO compounds for spintronics applications

Researchers have been making persistent efforts in recent years to find novel and suitable oxide materials with room temperature d0 ferromagnetic characteristics to be utilized in spintronics devices. The fundamental goal of this work is to investigate the effect of K/Mg co-doping on the structural, magnetic, optical, and transport (dielectric and Hall Effect) properties of Zn0.94−yK0.06MgyO compounds produced via solid-state process (y = 0, 0.02, 0.04, 0.06, 0.08). The X-ray diffraction pattern examination of these compounds revealed their hexagonal wurtzite structure. The Raman spectrum also displays the hexagonal wurtzite structure of ZnO without any lattice disorder. The elemental colour mapping demonstrates that all of the elements are dispersed uniformly throughout the compound. The concentration of K/Mg co-doping was increased, and this resulted in an improvement in the dielectric value and ac conductivity. Moreover, low dielectric loss in these compounds is observed and thus projecting it as a potential material to be utilized in high-frequency optoelectronic devices. The analyses of Nyquist plots show that higher Mg co-doping results in an increase of non-Debye kind relaxation and it led to a decrease in the grains and grain boundaries resistance. According to the analysis of dielectric data using the Maxwell-Wagner model, hopping of charge carriers are likely to be responsible for the electrical transport. As revealed from optical property measurement, the band gap was found to be slightly altered and the transmittance value increased from 82% for Zn0.94K0.06O to 86% for K/Mg co-doped ZnO compounds. The Hall Effect investigation clearly indicated p-type conductivity and enhanced carrier density concentration. Furthermore, it has been discovered that these substances exhibit ferromagnetism at room temperature.

Blending with transition metals improves bioresorbable zinc as better medical implants.

Zinc (Zn) is a new class of bioresorbable metal that has potential for cardiovascular stent material, orthopedic implants, wound closure devices, etc. However, pure Zn is not ideal for these applications due to its low mechanical strength and localized degradation behavior. Alloying is the most common/effective way to overcome this limitation. Still, the choice of alloying element is crucial to ensure the resulting alloy possesses sufficient mechanical strength, suitable degradation rate, and acceptable biocompatibility. Hereby, we proposed to blend selective transition metals (i.e., vanadium-V, chromium-Cr, and zirconium-Zr) to improve Zn's properties. These selected transition metals have similar properties to Zn and thus are beneficial for the metallurgy process and mechanical property. Furthermore, the biosafety of these elements is of less concern as they all have been used as regulatory approved medical implants or a component of an implant such as Ti6Al4V, CoCr, or Zr-based dental implants. Our study showed the first evidence that blending with transition metals V, Cr, or Zr can improve Zn's properties as bioresorbable medical implants. In addition, three in vivo implantation models were explored in rats: subcutaneous, aorta, and femoral implantations, to target the potential clinical applications of bioresorbable Zn implants.

Correction to: Investigations on electronic and optical properties of Zn:CdO‑PVDF polymer composite thin films

Correction to: Investigations on electronic and optical properties of Zn:CdO‑PVDF polymer composite thin films

Synthesis, Physicochemical, Thermal and Antioxidative Properties of Zn(II) Coordination Compounds with Pyrazole-Type Ligand

The reactions of pyrazole derivative, i.e., ethyl-5-amino-1-methyl-1H-pyrazole-4-carboxylate (L) with zinc halogenides in methanolic solution and zinc nitrate and zinc acetate in acetonic solution are described. The formulae of synthesized compounds are ZnL2Cl2 (1), [ZnL2Br2] (2), ZnL2I2·0.5MeOH (3), [Zn(L)2(H2O)4](NO3)2 (4), and {ZnL(OAc)2}2 (5). Two complexes are obtained in form of single crystals: [ZnL2Br2] (2) and [Zn(L)2(H2O)4](NO3)2 (4). Their crystal and molecular structure were determined by single-crystal X-ray structure analysis. The FTIR spectra of compounds prove the complex formation with all five zinc salts. The complexes are characterized by conductometric and thermoanalytical measurements, and their antioxidative activity was also tested by the scavenging effect on the DPPH radical. Conductometric results, solvolytic stability, and antioxidative activity of the compounds are in correlation.

Investigations on electronic and optical properties of Zn:CdO-PVDF polymer composite thin films

Investigations on electronic and optical properties of Zn:CdO-PVDF polymer composite thin films

Synthesis, Structure and Luminescent Properties of Zn(Ii) Metalorganic Frameworks Constructed by Flexible and Rigid Ligands

Synthesis, Structure and Luminescent Properties of Zn(Ii) Metalorganic Frameworks Constructed by Flexible and Rigid Ligands

Experimental investigation and empirical modeling for corrosion rate prediction of biodegradable zinc based composite considering the effect of constituent materials

Biodegradable zinc (Zn) has shown great potential in the area of biomedical applications. Though, the mechanical properties are decisive for the use of Zn for orthopedic and cardiovascular applications. Consequently, one needs to focus on improving the mechanical properties of Zn for its suitability in biomedical applications. Alloying of essential elements of the human body resulted in enhancement of Zn’s mechanical properties in recent years. The corrosion rate of pure Zn is ideal; however, the addition of other elements has resulted in a loss of its ideal corrosion rate. The inclusion of hydroxyapatite (HA) and iron (Fe) in Zn has also been reported in improving the mechanical properties. Hence, a need is raised for the development of a model which can predict the corrosion rate after adding HA along with Fe in Zn. In this research work, empirical based modeling is proposed to predict the corrosion rate, which incorporates the outcome of addition of Fe and HA in Zn. The Zn based materials were fabricated with the help of microwave sintering for developing the empirical model. The corrosion properties of the materials were assessed through a potentiodynamic polarization test in a simulated body fluid solution. The enhanced corrosion rate was attained with the rise in HA (wt%) and Fe (wt%) in Zn. An empirical correlation was established between the influencing controlling parameters (i.e., corrosion current, equivalent weight, and material density) of corrosion rate. Confirmation experiments were conducted to validate the developed model, and the highest error of 6.12% was obtained between the experimental and predicted values exhibiting the efficaciousness of the proposed model.

Investigation on tribological behaviors of biodegradable pure Zn and Zn-X (Li, Cu, Ge) binary alloys

As a potential biodegradable implant material, zinc (Zn) alloys have attracted increasing attention due to their good biocompatibility and moderate degradation rate. Zn and its alloys are expected to become candidate materials for medical devices. The metals implanted in the human body will inevitably undergo friction in the human body before it is completely degraded. Friction and wear are essential factors which may cause medical devices’ service failure. However, there are still few studies on the friction and wear properties of biodegradable Zn-based alloys in the human body, and most studies just focus on the mechanical properties, degradation properties and biocompatibility of the alloys. Thus, it is crucial to study the friction and wear properties of Zn and its alloys. In the present work, we investigated the tribological properties of biodegradable pure Zn and Zn-X (Li, Cu, Ge) alloys. Our study found that under simulated body fluid and dry friction conditions, the addition of alloying elements Li and Cu can improve the friction properties of Zn. Among the four metals, Zn-0.5Li alloy has the lowest friction coefficient and the best wear resistance. Hank’s solution has lubricating and corrosive effects. That is to say, when the alloy is rubbed in Hank’s solution, it can not only be protected by the lubrication of the solution, but also tribocorrosion will occur as well.

Template Synthesis of Ag2S-Zn0.5Cd0.5S with two structures and their application in RhB’s Photodegradations

Two kinds of Ag2S-Zn0.5Cd0.5S heterostructural photocatalysts were synthesized via a simple two-step hydrothermal method. The photochemical (PEC) properties of Zn0.5Cd0.5S nanoparticles modified by Ag2S are closely related to the reaction time of Zn0.5Cd0.5S nanoparticles. Compared with the Ag2S-Zn0.5Cd0.5S heterostructure prepared at low temperature, the Ag2S-Ag-Zn-Cd-S composite prepared at high temperature has higher charge transfer/separation efficiency and longer carrier life. The photocatalytic performance of Ag2S-Ag-Zn-Cd-S composites for the degradation of Rhodamine B (RhB) under visible light irradiation (λ = 420 nm) was significantly improved. The AZCS-180-4 h photocatalyst exhibited the highest degradation efficiency (83.1% within 40 min) with a rate constant of 0.0401 min−1 which exhibited prominent stability and repeatability, and can still maintain high photocatalytic activity after at least four cycles. Meanwhile, the study of photocatalytic mechanism shows that the photo-induced h+ radical is the predominant active species in this photocatalytic system, followed by·OH and·O2- play a secondary role.

Preparation and modification of ZnSb-based phase change storage films

In this study, the mechanical and electrical properties of Zn–Sb thin films with different Zn contents were focused; the corresponding improvement mechanism is also discussed. It is found that the maximum phase transition temperature of the film is 250 °C when the Zn content is about 50 at%. The crystallization activation energy of the film also reached a maximum of 4.549 eV. The micro-structure analysis result of these annealed films through XRD showed that when the Zn content is less than 50 at.%, the Sb crystallization firstly reduces the amorphous thermal stability of the material, while the film with the highest crystallization activation energy forms the ZnSb phase. Besides, adding N element greatly increases the resistance ratio of the film before and after the phase change and the phase change temperature point, the maximum temperature reaches 265 °C, and the resistance ratio reaches 104 orders of magnitude. The doping of N also increases the density of the deposited film. When the N content is less, some N elements fill the defects caused by physical deposition, increase the density of the film, and increase the phase transition temperature of the film. The N atoms in the film are more likely to bond with Zn when N content is high, forming a Zn–N bond, and even forming a Zn3N2 phase, so that the phase transition temperature of the film is lowered.

A fumarole in a one-pot: synthesis, crystal structure and properties of Zn- and Mg-analogs of itelmenite and a synthetic analog of glikinite

Anhydrous sulfate minerals are abundant in the active fumaroles with highly oxidizing conditions on the scoria cones of the Tolbachik volcano. The mineral itelmenite, ideally Na2CuMg2(SO4)4, containing isomorphous admixture of Zn, was described in 2018, whereas glikinite, ideally Zn3O(SO4)2, was described in 2020. Synthetic analogs of both minerals were obtained during studies of phase formation in the Na2SO4–CuSO4–MgSO4–(ZnSO4) systems which lead to essentially different results. Solid-state syntheses resulted in formation of several compounds previously known as minerals only. Both Zn- and Mg-containing analogs of itelmenite were prepared and exhibit slight deviations from the ideal Na2CuM2(SO4)4 stoichiometry. The Mg compound could be prepared single-phase which allowed the study of its thermal expansion and IR spectroscopy. Na2CuMg2(SO4)4 and Na2CuZn2(SO4)4 were evaluated for Na+-ion diffusion. For the Zn compound, several by-products were observed which are synthetic analogs of puninite Na2Cu3O(SO4)2, as well as hermannjahnite CuZn(SO4)2 and glikinite-type (Zn,Cu)3O(SO4)2. All of them were prepared via solid-state reactions in open systems. The Na2CuMg2(SO4)4, Na2CuZn2(SO4)4 and (Zn,Cu)3O(SO4)2 were structurally characterized by the single-crystal XRD. In the Zn-bearing system, the admixture of Cu2+ likely controls the formation of itelmenite-type and glikinite-type phases. The results of the experiments allowed to deduce possible scenarios of the formation processes of itelmenite and some other endemic fumarolic minerals. Our study shows that outstanding mineralogical diversity observed in the fumaroles of the Tolbachik scoria cones is not only due to the formation from the gas enriched by transition metals and involves also intensive exchange with the host basaltic scoria. Similar processes seem also to be responsible for the recrystallization of many other mineral species observed in high-temperature fumaroles resulted from the recent eruptions.

Synthesis, crystal structures, and luminescent properties of Zn(II)/Cd(II) complexes assembled by 4-aminophenylhydroxamic acid

Two coordination complexes, namely [Zn2(4-APha)2(CH3COO)2(H2O)2] (1) and [Cd(4-APha)·(CH3COO)(H2O)0.5]4·6H2O (2) (4-APha = 4-aminophenylhydroxamic acid), are synthesized by the solvothermal method. They are characterized by single crystal X-ray diffraction, IR, TGA, and elemental analysis. Structural analyses reveal that both complexes 1 and 2 belong to the monoclinic system, space group C2/c. The difference is that complex 1 shows a binuclear structure and complex 2 displays a 3D structure. It is noteworthy that complex 1 exhibits an excellent thermal stability and no weight loss below 117 °C. Meanwhile, the luminescent pro­perties of complexes 1 and 2 in the solid state are also investigated at room temperature.

Structure, physical, dielectric and magnetic properties of Zn1– x Co x O nanoparticles prepared via coprecipitation method

Zn1– x Co x O nanoparticles have been prepared by coprecipitation method. X-ray diffraction study confirms the polycrstalline nature with hexagonal wurtzite ZnO structure of the Zn1– x Co x O nanoparticles. The W–H analysis results confirms the mean crystallite size of the Co-doped samples was increased from 62 to 72 nm. All samples have nanocrystalline particles were investigated by field emission scanning electron microscopy. Optical absorption studies showed a red shift absorption spectra due to the incorporation of Co atoms in ZnO lattice. Dielectric constant and dielectric loss were decreasing with increasing Co content. Magnetic hysteresis loops of prepared nanoparticles exhibit paramagnetic behavior at room temperature.

Structure, Composition, and Properties of Zn- and O-Ion Implanted Silicon at Elevated Temperatures

Czochralski-grown Si substrates (n-type, orientation (100)) are subjected to double implantation, notably, initially by 64Zn+ ions with a dose of 5 × 1016 cm–2 and an energy of 50 keV and then with 16O+ ions with a dose of 2 × 1017 cm–2 and an energy of 20 keV. The substrates during implantation are held at ~350°C. The implanted Si substrates contain radiation-induced defects and their clusters such as twins, dislocations, and nanoclusters, notably, Zn-containing nanoclusters with an average radius of 10–50 nm predominantly consisting of the metallic Zn phase and partially from the ZnO phase formed on the surface and in the substrate near-surface layer. Photonic annealing to an effective temperature of 700°C optimal for the formation of the ZnO phase leads to the annealing of radiation-induced defects, and Zn-containing nanoclusters presumably consisting of the ZnO phase and partially of the Zn2SiO4 phase with an average diameter of 50–100 nm are recorded on the sample surface.

Syntheses, crystal structures, and properties of Zn(II), Cd(II), and Co(II) complexes based on 2-methyl-4-chlorophenoxyacetic acid and various N-donor ligands

Six novel mixed-ligand complexes, [Cd(MCPA)2(bbhb)] n (1), [Cd(MCPA)2(bib)2] n (2), [Co2(MCPA)4(pbix)2] (3), [Zn(MCPA)2(pbix)2] n (4), [Cd(MCPA)2(obix)2] n (5), and [Co(MCPA)2(obix)2] n (6), have been synthesized under hydrothermal conditions and structurally characterized, where MCPAH = 2-methyl-4-chlorophenoxyacetic acid, bbhb = 1,1′-(1,4-butanediyl)bis-1H-benzimidazole, bib = 1,4-bis(imidazol-1-yl)-butane, pbix = 1,4-bis(imidazol-1-ylmethyl)benzene and obix = 1,2-bis(imidazol-1-ylmethyl)benzene. X-ray diffraction analyses reveal that the N-donor ligands bridge the metal centers into different 1 D chains in complexes 1, 2, 4, 5, and 6, while three is a dinuclear molecule containing 26-membered ring. Furthermore, the luminescent properties of 1, 2, 4, and 5 are also presented.

Microstructural evolution and mechanical properties of multi-directionally forged SiP/ZA22 composite

The effect of multi-pass multi-directional forging (MDF) on the microstructure and mechanical properties of Zn–22Al–xSi (X = 4 and 8 wt. %) alloy, also known as SiP/ZA22 composite, was investigated. MDF process was applied at 100 °C for one, three, and five passes with the strain of 0.47 per pass. According to the results, MDF refined and homogenized the composites microstructure so that the average size of primary Si (SiP) particles reduced from 25.0 µm and 30.4 µm in as-cast ZA22-4Si and ZA22-8Si composites to about 6.2 µm and 7.3 µm in five-pass MDFed condition, respectively, and their distribution shifted to the smaller size range. Mechanical properties tests revealed that multi-pass MDF has softened the investigated composite. For instance, the hardness, tensile strength, and shear strength of ZA22-4Si composite reduced from 83 HV, 280 MPa, and 165 MPa in as-cast condition to about 58 HV, 160 MPa, and 118 MPa in the five-pass MDFed sample, respectively. This is while its fracture strain increased from 15% to about 40% with the strain rate of 1.2 × 10–3 s−1.