Zinc Acetate Dehydrate Research Articles

Modulation of Physical Properties of Sprayed ZnO Thin Films by Substrate Temperature for Optical Applications

We investigated the structural, electrical and optical properties of zinc oxide thin films as the n-type semiconductor. In the present paper, the effect of substrate temperature on the synthesis of ZnO thin films was carried out from 250[Formula: see text]C to 500[Formula: see text]C. ZnO thin films were deposited on glass substrates via ultrasonic spray technique with 0.2[Formula: see text]mol/L of zinc acetate dehydrate. The crystal quality of the thin films was analyzed by X-ray diffraction which results in modified substrate temperature. The optical transmittance and electrical conductivity measurements were carried out by Ultraviolet-visible spectrophotometer and four-point methods, respectively. Polycrystalline films with a hexagonal wurtzite structure with (100) and (002) preferential orientation corresponding to ZnO films were observed at high temperature. The optimal values of the average crystallite size of the ZnO films under consideration are observed beginning with 350[Formula: see text]C of substrate temperature. All films exhibit an average optical transparency of about 85% in the visible region. The shift of optical transmittance toward higher wavelength can be shown by the increase of bandgap energy from 3.245[Formula: see text]eV to 3.281[Formula: see text]eV with increasing substrate temperature of 250–500[Formula: see text]C. The observed Urbach energy of ZnO thin films decreases from 0.11311[Formula: see text]eV to 0.04974[Formula: see text]eV. At a high temperature, the electrical conductivity of ZnO films was increased from [Formula: see text] to 41.58 ([Formula: see text].cm)[Formula: see text] with the increasing substrate temperature from 350[Formula: see text]C to 500[Formula: see text]C.

A study of Eu incorporated ZnO thin films: An application of Al/ZnO:Eu/p-Si heterojunction diode

In present work, the pure and europium (Eu) incorporated zinc oxide (ZnO) thin films were deposited with sol-gel spin coating by using zinc acetate dehydrate and Eu (III) chloride salts. The coated films were examined by means of XRD, AFM and UV/VIS spectrophotometer. The ZnO hexagonal wurtzite nanoparticles with (002) preferential direction were observed for all films. The values of crystallite size, micro-strain and surface roughness continuously increased from 21 nm, 1.10 × 10−3 and 2.43 nm to the values of 35.56 nm, 1.98 × 10−3 and 28.99 nm with Eu doping, respectively. The optical band gap value of the pure ZnO initially increased from 3.296 eV to 3.328 eV with Eu doping up to 2 at.% doping level, then it started to decrease with more Eu content. The electrical features of Al/n-ZnO:Eu/p-Si heterojunction diodes were inquired by current-voltage (I–V) measurements at the room temperature.

Growth of Nanostructured ZnO Nanosheet on ITO/PET Substrate Prepared via Sol Gel Spin Coating and Hot Water Treatment

Zinc Oxide (ZnO) is well known for its wide band gap semiconductor with large excitation energy that serves various application. These unique characteristics had gained much research attention on ZnO nanostructure synthesis and physical properties. In this study, ZnO thin films were deposited on ITO/PET substrate by a spin coating sol-gel process. The starting solution were prepare by dissolved zinc acetate dehydrate (ZnAc) and diethanolamine (DEA) in water (H2O) and 2-propanol (2-PrOH). Acid Citric (C6H8O7) from 0.2 to 1.0 M were dropped into 100 ml sol-gel solution to study effect of sol-gel environment condition. ZnO thin films were obtained after pre-heating the spin coated thin films at 100 °C for 5 minutes after each coating. The coated substrates were undergone for Hot Water Treatment (HWT) process at 90 °C for 6 hours to grow ZnO nanostructures. The effects of sol-gel environment condition by drop different concentrations of C6H8O7 into the solution were studied. Nanoflakes ZnO were obtained after hot water and hydrothermal treated at 90 °C for 6 hours with 0.2 till 1.0 concentration of C6H8O7 dropped directly in the sol-gel solution. On the basis of the changes in morphology and microstructure induced by hot water treatment, it is concluded that the nanosheets were highly transparent with the visible range (350 – 800 nm) with 70%-90% of Transmittance spectra. Growth of ZnO nanosheet influenced by increment of C6H8O7 mol concentration also with value of roughness RMS.

Effect of Crystallite Size on the Optical and Structural Properties of Gadolinium-Doped Zinc Oxide

Rare earth Gd-doped ZnO thin films were prepared by a simple sol-gel spin coating method in order to search for a new functional diluted magnetic semiconductor for potential application in spintronics. The thin films were deposited onto glass substrates with zinc acetate dehydrate, monoethanolamine and 2-methoxyethanol as a starting material, stabilizer and solvent, respectively. The dopant percentage was increased up to 8%. Optical investigation showed that the crystallinity of the thin films was changing due to the increase of the Gd concentrations and optical band gap energy (Eg) value was estimated to be around 3.12 ~ 3.28 eV using Tauc's model. The crystallite size determined from XRD spectra and the results was found that the value is in the range of 14.42 ~ 21.98 nm.

Synthesis of ZnO Nanostructures Using Sol-Gel Method

Zinc oxide plays an important role in current industry due to its special characteristics such as anti-corrosion, anti-bacteria, has low electrons conductivity and excellent heat resistance. Therefore, the objective of this study is to synthesize zinc oxide nanostructures with the most practical ways by using sol-gel method and characterize the nanostructures. Sol-gel method is the simplest method and has the ability to control the particle size and morphology through systematic monitoring of reaction parameters. ZnO nanoparticles were synthesized via sol gel method using Zinc acetate dehydrate (Zn(CH3COO)2.2H2O) as a precursor and ethanol (CH2COOH) was used as solvent, Sodium hydroxide (NaOH) and distilled water were used as medium. ZnO nanoparticles were characterized by using XRD, EDX, FESEM, and nano-particles analyser. Result of EDX characterization shows that the ZnO nanoparticles has good purity with (Zinc content of- 55.38% and; Oxygen content of- 44.62%). XRD result spectrum displays mainly oxygen and zinc peaks, which indicate the crystallinity in nature as exhibited. FESEM micrographs shows that synthesized ZnO have a rod-like structure. The obtained ZnO nanoparticles are homogenous and consistent in size which corresponds to the XRD result that exhibit good crystallinity. ZnO nanoparticles were successfully synthesized by sol-gel method in nanosize range within 81.28nm to 84.98nm.

Synthesis and Characterisation of Titanium Dioxide and Zinc Oxide Nanoparticle

Metal nanoparticles have been intensively studied within the past decade. Nanosized materials have been an important subject in applied sciences and engineering. Zinc oxide and Titanium oxide nanoparticles have received considerable attention due to their unique antibacterial, antifungal, and UV filtering properties, high catalytic and photochemical activity. In present work, ZnO and TiO2 nanoparticles were synthesized and characterized. The TiO2 nano particles were prepared according to the Co-precipitation method by hydrolysis and condensation of titanium tetraisopropoxide in absolute ethanol. ZnO nanoparticles were generated by thermal decomposition of a binuclear zinc (II) curcumin complex as single source precursor Zinc acetate dehydrate and triethnolamine (TEA) were used as the precursor materials. The as-synthesized TiO2 and ZnO particles were characterized by Particle size analyser and UV Visible Spectroscopy. The pariticle size of ZnO nanoparticle is 340 nm and TiO2 nanoparticle is 579 nm. The band-gap energy (Eg) was determined based on numerical derivative of the optical absorption coefficient by using UV-visible spectroscopy. The band gap is found to be 3.17eV & 3.18eV for the ZnO nanoparticles and TiO2. Thus, from the value of band gap obtained is 3.17eV and 3.18eV respectively.

Comparative study of accurate experimentally determined and calculated band gap of amorphous ZnO layers

In this work, amorphous ZnO thin films were prepared by sol–gel technique using zinc acetate dehydrate and diethanol amine. The synthesized films have been deposited on glass substrates and heated at 150°C. X-ray diffractions have been carried out to analyze the fabricated films structure. The optical transmission in the UV–visible spectral range is found to be important characteristic to assess the quality of the deposited layers. The X ray diffraction results indicated that the zinc oxide structure is amorphous, after instant preparation of the precursor sols. The as prepared films exhibited UV transmittance at around 85% in visible range with the estimated direct band gap energy varying from 3.6 to 3.2 eV when the layer thickness increases from 400nm to 1μm.The obtained results are assessed by Comparative study of accurate theoretical bandgap calculations of ZnO thin films and experimentally determined band gap of amorphous ZnO layers. Theoretical calculations of ZnO band gap was performed by the full potential linearized augmented plane wave (FP-LAPW) method with the modified Becke-Johnson (mBJ) potential and via generalized gradient approximation (GGA). After careful analysis of the results presented in this work we have deduced that the mBJ potential is found to be more efficient in the calculations of band gap.

Studies on Effect of Zinc Oxide (ZnO) Nanostructures Morphology by Modification of Sol-Gel Solution

Zinc Oxide (ZnO) known as wide band gap semiconductor with large excitation energy 60 meV, noncentral symmetry, piezoelectric and biocompatible for biomedical application are the unique characteristic that attract many researcher’s attention on ZnO nanostructure synthesis and physical properties. ZnO thin films were deposited on Si Glass substrate by a sol-gel process. The starting solution were prepare by dissolved zinc acetate dehydrate (ZnAc) and diethanolamine (DEA) in water (H2O) and 2-propanol (2-PrOH). 0 to 60 drops of NaOH were dropped into 100 ml sol-gel solution to study effect of sol-gel modification. ZnO thin films were obtained after preheating the spin coated thin films at 100 °C for 10 minutes after each coating. The coated substrates were undergone for Hot Water Treatment (HWT) process at 90 °C for 6 hours to grow ZnO nanostructures. The effects of sol-gel modification by drop of NaOH into the solution were studied. ZnO nanorods and nanoflakes were obtained after hot water treated at 90 °C for 6 hours with different amount of NaOH dropped directly in the sol-gel solution. On the basis of the changes in morphology and microstructure induced by hot water treatment, it is concluded that the amount of NaOH dropped into sol-gel effected morphology of ZnO growth.

Ergonomic Synthesis Suitable for Industrial Production of Silver-Festooned Zinc Oxide Nanorods

For maximizing productivity, minimizing cost, time-boxing process and optimizing human effort, a single-step, cost-effective, ultra-fast and environmentally benign synthesis suitable for industrial production of nanocrystalline ZnO , and Ag -doped ZnO has been reported in this paper. The synthesis based on microwave-supported aqueous solution method used zinc acetate dehydrate and silver nitrate as precursors for fabrication of nanorods. The synthesized products were characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy and UV-Vis–NIR spectroscopy. The undoped and Ag -doped ZnO nanorods crystallized in a hexagonal wurtzite structure having spindle-like morphology. The blue shift occurred at absorption edge of Ag -doped ZnO around 260 nm compared to 365 nm of bulk ZnO . The red shift occurred at Raman peak site of 434 cm-1compared to characteristic wurtzite phase peak of ZnO (437 cm-1). The bandgap energies were found to be 3.10 eV, 3.11 eV and 3.18 eV for undoped, 1% Ag -doped, and 3% Ag -doped ZnO samples, respectively. The TEM results provided average particle sizes of 17 nm, 15 nm and 13 nm for undoped, and 1% and 3% Ag -doped ZnO samples, respectively.

Deposition of Ag 2~6 mol%-Doped ZnO Photocatalyst Thin Films by Thermal Spray Coating Method for E.coli Bacteria Degradation

ZnO doped with 2~6 mol% Silver (Ag) photocatalyst thin films has been deposited on glass substrate by thermal spray coating with temperature deposition of 250°C. A gel of ZnO:Ag precursor has been synthesized by sol-gel route from aqueous/alcoholic solution of zinc acetate dehydrate and silver nitrate mixture at room temperature. The morphology of ZnO:Ag films were investigated scanning electron microscopy (SEM). 3D SEM images of ZnO:Ag thin films show the rough morphology with roughness mean square (rms) of 150 to 195 nm. The grain size of ZnO:Ag films were found in the range 76,5 to 304,8 nm. The photoactivity examination of ZnO:Ag photocatalyst films show the E. Coli bacteria degraded up to 99.99% under sunlight irradiation for 4 hours.

Effects of Sn Dopant on Structural and Optical Properties of ZnO Thin Film Prepared by Sol-Gel Route

Tin doped zinc oxide (Sn:ZnO) thin films were prepared on glass substrates via sol-gel dip-coating technique starting from zinc acetate dehydrate, (CH3CO2)2Zn⋅2H2O and tin chloride, SnCl2. The consequences of various Sn doping on the behavior of the film was investigated. The atomic percentages of dopant in ZnO-based solution were [Sn4+]/[Zn2+] which is between 0% and 4%. The thin films were characterized using Field Emission Scanning Electron Microscope (FESEM) and UV-Vis-NIR spectrophotometer.

Phase formation of hexagonal wurtzite ZnO through decomposition of Zn(OH)2 at various growth temperatures using CBD method

Zinc oxide (ZnO) nanophosphors were fabricated from zinc acetate dehydrate, thiourea and ammonia via the chemical bath deposition (CBD) method at various growth temperatures. TGA results showed the increase in thermal stability of ZnO with the increase in growth temperature. From DSC results we observed a decrease in melting temperatures due to the crystallization of the ZnO with the increase in growth temperature. The melting enthalpy values were too scattered to make definite conclusions. XRD indicated the decomposition of structure from Zn(OH)2 to hexagonal wurtzite ZnO. The estimated average particle sizes are in the range of 22nm. The estimated average particle size fluctuated with an increase in the growth temperature. The SEM morphology showed the full formation of flakes-like at high growth temperature. At low growth temperature shows flakes-like morphology combined with some small spheres. The EDS results confirmed the presence of Zinc (Zn) and Oxygen (O) as the major products, and the ratio of the Zn to O increased with the increase in growth temperature. A red-shift in reflectance spectra was observed, which resulted in the decrease in the band gap energy of the ZnO with an increase in growth temperature. The temperature dependent PL spectra of the ZnO showed visible emission due to defects. The novelty in this study lies within the increase in the amount of weight loss observed from TGA and DSC analysis and another important aspect is the transformation of Zn(OH)2 to the well-known hexagonal wurtzite structure of ZnO with the increase in growth temperature. This study provides a simple and efficient approach for the synthesizing of the ZnO with flakes-like morphology.

Synthesis and characterization of a new anionic zinc-adeninate metal–organic framework, [Zn3(ad)(BTC)2·(Me2NH2), 5.75 DMF, 0.25 H2O

A new anionic zinc-adeninate metal–organic framework, [Zn3(ad)(BTC)2·(Me2NH2), 5.75DMF, 0.25H2O] (ad = adeninate; BTC = benzene tricarboxylate; DMF = dimethylformamide), was synthesized via solvothermal reaction at 403 K for 24 h between adenine, zinc acetate dehydrate, and benzene tricarboxylic acid in DMF. The single-crystal structure of the framework was determined by single-crystal X-ray diffraction techniques in the monoclinic space group P2(1)/n and was refined to the final error indices R1/wR2 = 0.0663/0.1714 for I > 2sigma(I). The coordination of adenine and BTC expands the structure in different directions, resulting in a three dimensional structure. This framework contains a pore with the size ca. 6.6 × 3.9 A. The chemical stability, thermal stability, and cation-exchange characteristics were investigated by powder XRD, TGA, EDX, 1H NMR, and EA.

Effect of growth temperature and time on the ZnO film properties and the performance of dye-sensitized solar cell (DSSC)

This paper reports the synthesis of ZnO nanorods via seed-mediated growth hydrothermal technique and their application in dye-sensitized solar cells (DSSCs). The growth process was carried out at various temperatures, namely 60, 70, 80, and 90 °C for 8 h at 0.1 M zinc acetate dehydrate (ZAD) to investigate the effect of growth temperature on the property of ZnO sample and on the performance of the DSSC-containing ZnO sample. The growth process was also carried out at various growth times, namely 2, 4, 6, and 8 h at 90 °C at 0.1 M ZAD to investigate the effect of growth time on the property of ZnO sample and on the performance of the DSSC. It was found that the morphology of ZnO nanorods in terms of grain size and length increases with the growth temperature. The peak intensity of XRD patterns, crystallite size, optical absorption, and photocurrent also increase with the growth temperature. The optical absorption and power conversion efficiency (η) increase as the growth time increases. The DSSC utilizing the ZnO nanorods synthesized at 90 °C for 8 h demonstrates the JSC, VOC, FF and η of 1.860 mA cm−2, 0.52 V, 0.287, and 0.277 %, respectively.

Parametric Study of Sol Gel Technique for Fabricating ZnO Thin Films

Zinc Oxide (ZnO) thin films were prepared by sol gel method. Zinc acetate dehydrate, Methanol and Diethanolamine were used as a starting material, solvent and stabilizer respectively. The influence of aging time (18, 24 and 48hours), annealing temperature (300, 400 and 500°C) and spinning speed (1500, 2500 and 3500rpm) on crystal size and surface roughness of the thin films was investigated using L9 Orthogonal Array. Structural and Morphological characteristics of the films were analysed by Atomic Force Microscopy and X-Ray Diffractometer. Annealing temperature had 84.53% influence on crystal size and 81.07% on surface roughness of the films. Grey Relation Analysis indicated that parameter levels of 48hours, 1500rpm and 300°C yields crystal size of 20.79nm and surface roughness of 186.97nm.

Sonochemical Assisted Synthesis of ZnO Nanostructured thin Films Prepared by Sol-gel Method

In this article, the effect of applying sonication on the characteristics of zinc oxide (ZnO) thin films prepared by sol-gel method is investigated. ZnO films were deposited on glass substrates using spin coating technique. Zinc acetate dehydrate, ethanol, and triethylamine were used as the zinc source, solvent, and stabilizer, respectively. The as-deposited films were dried at 300°C for 10min. The spin-coating and drying steps were repeated for depositing ten layers to reach the desired thickness. X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and UV-Vis spectroscopy analyses were used to study the crystallinity, morphology, and optical properties of the films. XRD spectra show that the samples were crystallized in wurtzite structure and sonication treatment has no effect on crystal phase. However, the crystallinity and preferred orientation growth were remarkably changed. The average grain size observed by FESEM for sonicated films is larger than those for films without sonication. UV-Vis spectroscopy shows that optical band gap energy slightly decreases by sonication.

Controlling Diameter, Length and Characterization of ZnO Nanorods by Simple Hydrothermal Method for Solar Cells

Zinc oxide (ZnO) nanorods have been synthesized by solution processing hydrothermal method in low temperature using the spin coating technique. Zinc acetate dehydrate, Zinc nitrate hexahydrate and hexamethylenetetramine were used as a starting material. The ZnO seed layer was first deposited by spin coated of ethanol zinc acetate dehydrate solution on a glass substrate. ZnO nanorods were grown on the ZnO seed layer from zinc nitrate hexahydrate and hexamethylene-tetramine solution, and their diameters, lengths were controlled by precursor concentration and development time. From UV-Visible spectrometry the optical band gap energy of ZnO nanorods was calculated to be 3.3 eV. The results of X-Ray Diffraction (XRD) showed the highly oriented nature of ZnO nanorods the hardest (002) peak reflects that c-axis elongated nanorods are oriented normal to the glass substrate. The Field Emission Scanning Electron Microscope (FESEM) was employed to measure both of average diameter of ZnO nanorods, Energy Dispersive X-Ray (EDX) is used to identify the elemental present and to determine the element composition in the samples.

Effects of Polyethyleneimine on the Sonochemical Synthesis of Gadolinium Ion-Modified ZnO Nanorods.

We prepared gadolinium (Gd) ion-modified ZnO nanorods by a sonochemical decomposition of zinc acetate dehydrate and gadolinium acetate hydrate precursor solutions with and without polyethyleneimine (PEI). We investigated the effects of PEI on the sonochemical synthesis of ZnO nanorods with and without Gd ion modifications. In the case of nascent ZnO nanorods, PEI in the precursor solutions can prohibit radial growth but allow axial growth, resulting in changes in the degree of preferred crystal orientations, and in the PL properties of the resulting nanorods. In the case of Gd ion-modified ZnO nanorods, we observed that the ZnO nanorods, fabricated sonochemically in the precursor solutions with PEI, exhibited a peak broadening of the ZnO(002) crystal plane and decreasing crystal orientation with respect to the c plane. We note that PEI can negatively affect the crystal orientation and crystallinity of Gd ion-modified ZnO nanorods, even though it cannot affect the lattice constant.

Synthesis and electrochemical performance of ZnCo2O4 for lithium-ion battery application

ZnCo2O4 was synthesized through the rheological phase reaction method using zinc acetate dehydrate, cobalt (II) acetate tetrahydrate, and citric acid as raw materials. The precursors were heat-treated in a muffle furnace at 400°C or 500°C, respectively. The samples were characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The electrochemical properties of the samples were investigated. The results show that ZnCo2O4 nanoparticles were synthesized successfully. The particles took on irregular quasi-spherical shapes, and the sizes of the particles were less than 100nm. The electrochemical properties showed that the ZnCo2O4 synthesized at 400°C featured better reversible capacity than that of ZnCo2O4 synthesized at 500°C, and its specific capacity was 801mAhg−1 after 100 cycles at a constant current of 100mAhg−1 in the voltage range of 0.01–3V. Hence, the ZnCo2O4 synthesized by this method could be a promising anode material for lithium ion battery application.

Effect of zinc acetate dihydrate precursor concentration on the properties of TiO2–ZnO core–shell nanograss hetero-structure

TiO2–ZnO core shell nanograss (NG) hetero-structure was synthesized via two-step synthesis techniques, namely, liquid phase deposition (LPD) to prepare the TiO2 core nanograss and dip-coating technique to prepare the ZnO shell onto the core. The effect of the concentration of zinc acetate dehydrate (ZAD) precursor on the properties of TiO2–ZnO core shell has been investigated. The FESEM characterization reveals that the TiO2 NG has high density of nanobranch with sharp multiple arms. The morphological observation shows that 0.15M is the optimum ZAD concentration in forming the TiO2–ZnO core–shell NG. It was found that the morphology changes from nanograss to nanoparticle as the concentration of ZAD is further increased to 0.20M. The structural characterization by XRD confirms that the formation of anatase TiO2 and wurzite ZnO phases in the core–shell structure. The crystallite size of the TiO2 core decreases with the concentration of ZAD. The optical absorption of the sample increases with the concentration of ZAD in the wavelength range of 350–380nm.