Zinc Acetate Precursor Research Articles

Synthesis, structure and photoelectrochemical behaviour of ZnO coatings on AISI 304 type steel

ZnO nanoparticles were prepared by thermal decomposition of precursor zinc acetate. Using electrophoretic deposition (EPD) ZnO coatings on AISI 304 steel were formed. The optimum deposition conditions for ZnO coatings were experimentally determined. The effects of synthesis conditions on the structure, morphology, composition and electrochemical properties of deposited coatings were studied by differential scanning calorimetry and thermogravimetry (DSC–TG) analysis, X-ray diffraction (XRD), Fourier-transform infrared (FTIR) analysis and photo-voltammetry. The photoelectrochemical performance of the prepared ZnO films was evaluated in a 0.1 M Na2SO4 aqueous solution. Also, the as-prepared photocatalysts were modified with a cobalt-based (Co–Pi) oxygen evolving catalyst (OEC) using photo-assisted deposition. The voltammetric characteristics revealed that the presence of a cobalt-based catalyst effectively changes the photoelectrocatalytic activity of oxide particles.

Multi-response optimization of ZnO thin films using Grey-Taguchi technique and development of a model using ANN

Spray pyrolysis deposited zinc oxide films have been prepared using zinc acetate precursor in iso-propyl alcohol (IPA). Based on deposition parameters, outputs were optimized for multiple performance characteristics such as thickness, roughness, and an optical transmittance of ZnO films using Grey-Taguchi technique. Optimum parameters from Grey relational analysis (GRA) were found to be 0.2M, 1bar, 365°C, and 5mLmin−1. The average thickness, roughness, and an optical transmittance obtained at the optimum condition using GRA were 79nm, 1.88nm, and 85.96% respectively as compared to the results obtained at optimized condition by a Taguchi method were 95nm, 2.45nm, and 85.19%, respectively. This indicated that the design proposed by Grey relational technique is a feasible approach for determining the optimal parameters. Further, the best condition was predicted by artificial neural network (ANN) and it was observed using cascade forward back propagation algorithm, tangent sigmoid transfer function as a hidden layer, and 4-8-3 topology.

Zinc Oxide-Supported Copper Clusters with High Biocidal Efficacy for Escherichia coli and Bacillus cereus.

Cu clusters on ZnO have been prepared by a simple low-temperature solid-state reaction from their respective acetate precursors. The formation of metallic Cu along with a small quantity of CuO was influenced by the presence of the zinc acetate precursor. Although there is a lack of formation of any metallic Cu in the absence of zinc acetate, increase in the heating duration helps in the formation of increased metallic Cu. A mechanism for formation of the Cu@ZnO nanocomposite has been suggested. The prepared Cu@ZnO nanocomposite, with metallic Cu, was identified by X-ray diffraction studies followed by confirmation of clusters of the kind Cu9 and Cu18 by transmission electron microscopy and matrix-assisted laser desorption ionization time-of-flight mass spectrometry. The photoelectron spectroscopy is able to clearly distinguish the Cu from CuO, which is very well complimented by electron spin resonance analysis. The morphological feature of ZnO changes from flakes to rods on increasing the duration of heating, as shown by scanning electron microscopy (SEM) analysis. The observed Cu plasmonic band in UV–vis diffuse reflectance gets blue-shifted to 463 nm from its normally observed position of 550–580 nm possibly due to cluster formation and interaction with ZnO, the band gap of the latter getting red-shifted to 3.2–3.0 eV. The antibacterial activity of the synthesized Cu cluster–ZnO nanocomposites was investigated against Escherichia coli ATCC-25922 for Gram-negative and Bacillus cereus ATCC-10876 for Gram-positive bacteria. Tests were performed on a nutrient agar medium and liquid broth supplemented with different concentrations of nanoparticles. SEM analysis of the native and treated Gram-positive and Gram-negative bacteria established a high efficacy of biocide activity in 24 h, with 200 μg/mL of Cu@ZnO nanocomposites.

Green Synthesized Zinc Oxide (ZnO) Nanoparticles Induce Oxidative Stress and DNA Damage in Lathyrus sativus L. Root Bioassay System.

Zinc oxide nanoparticles (ZnONP-GS) were synthesised from the precursor zinc acetate (Zn(CH3COO)2) through the green route using the milky latex from milk weed (Calotropis gigantea L. R. Br) by alkaline precipitation. Formation of the ZnONP-GS was monitored by UV-visible spectroscopy followed by characterization and confirmation by energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), and X-ray diffraction (XRD). Both the ZnONP-GS and the commercially available ZnONP-S (Sigma-Aldrich) and cationic Zn2+ from Zn(CH3COO)2 were tested in a dose range of 0–100 mg·L−1 for their potency (i) to induce oxidative stress as measured by the generation reactive oxygen species (ROS: O2•−, H2O2 and •OH), cell death, and lipid peroxidation; (ii) to modulate the activities of antioxidant enzymes: catalase (CAT), superoxide dismutase (SOD), guaiacol peroxidase (GPX), and ascorbate peroxidase (APX); and (iii) to cause DNA damage as determined by Comet assay in Lathyrus sativus L. root bioassay system. Antioxidants such as Tiron and dimethylthiourea significantly attenuated the ZnONP-induced oxidative and DNA damage, suggesting the involvement of ROS therein. Our study demonstrated that both ZnONP-GS and ZnONP-S induced oxidative stress and DNA damage to a similar extent but were significantly less potent than Zn2+ alone.

Carbon monoxide gas sensing using zinc oxide film deposited by spray pyrolysis

This study was aimed to determine the carbon monoxide (CO) gas sensing ability of zinc oxide (ZnO) film fabricated by spray pyrolysis on glass substrate heated at 3000C using 0.2 M zinc acetate precursor solution. The temperature of the precursor solution was maintained at room temperature. Carbon monoxide gas was synthesized by mixing the required amount of formic acid and excess sulfuric acid in the ratio of 1:6 to produce CO gas concentrations of 100, 200, 300, 400, and 500 parts per million (ppm) v/v. There were five trials for each concentration. The films produced exhibited good sensor characteristics such as high linearity in current voltage relationship and voltage response versus concentration. Electrical characterization using the four-point probe showed a linear relationship between current and voltage with resistivity of 0.49 ohm-cm and R2 value of 0.994 The zinc oxide film exhibited a sensitivity of 0.19 Volt per 100 ppm of CO gas and linearity R2 value of 0.993.

Highly transparent and conductive indium-doped zinc oxide films deposited at low substrate temperature by spray pyrolysis from water-based solutions

In this paper, indium-doped zinc oxide (IZO) films were grown by spray pyrolysis, using zinc acetate and indium acetylacetonate precursors. The focus was on developing a solution recipe based on water as solvent, with only minor acetic acid content, as well as keeping the substrate temperature as low as possible—at 360 °C. The process is therefore environment friendly and energy efficient. Despite the challenging conditions, the resulting IZO films were highly transparent and conductive. Their texture deviates strongly from the (002) texture of ZnO and depends on the indium content, which also influences the resistivity. The latter attains its minimum for an indium concentration of 4 at.% in the solution and decreases for increasing film thickness, reaching the value of (5.0 ± 0.1) × 10−3 Ω cm, mainly due to the increase in carrier mobility. The stability of the resistivity after high dose of UV irradiation was found to increase with the carrier density and the film thickness. Thick, highly doped films show minimal resistivity modification even after a total dose of 12.1 kJ/cm2 UVA/UVB irradiation. Finally, to demonstrate its applicability in devices, the IZO electrode was used for the fabrication of a lead-perovskite absorber solar cell, yielding an energy conversion efficiency of 6% and 910 mV open-circuit voltage.

Supercritical Antisolvent Precipitation of Amorphous Copper-Zinc Georgeite and Acetate Precursors for the Preparation of Ambient-Pressure Water-Gas-Shift Copper/Zinc Oxide Catalysts.

A series of copper–zinc acetate and zincian georgeite precursors have been produced by supercritical CO2 antisolvent (SAS) precipitation as precursors to Cu/ZnO catalysts for the water gas shift (WGS) reaction. The amorphous materials were prepared by varying the water/ethanol volumetric ratio in the initial metal acetate solutions. Water addition promoted georgeite formation at the expense of mixed metal acetates, which are formed in the absence of the water co‐solvent. Optimum SAS precipitation occurs without water to give high surface areas, whereas high water content gives inferior surface areas and copper–zinc segregation. Calcination of the acetates is exothermic, producing a mixture of metal oxides with high crystallinity. However, thermal decomposition of zincian georgeite resulted in highly dispersed CuO and ZnO crystallites with poor structural order. The georgeite‐derived catalysts give superior WGS performance to the acetate‐derived catalysts, which is attributed to enhanced copper–zinc interactions that originate from the precursor.

Study on Zno Catalytic Activity in Salycilic Acid Degradation by Sonophotocatalysis

The preparation of ZnO via sol-gel preparation and the study on sonophotocatalytic activity are reported. ZnO was prepared by zinc acetate precursor and the characterisation of the material was conducted by XRD, gas sorption analyser, SEM-EDX and Diffuse Reflectance UV-Visible spectrophotometry. Catalytic activity of the semiconductor material was investigated using varying methods of salicylic acid destruction - photocatalytic, sonocatalytic and sonophotocatalytic. The results indicated that prepared ZnO has photocatalytic activity with the band gap energy value of 3.22 eV. From the tested catalytic system, sonophotocatalytic gives the best rate of salycilic acid destruction. The kinetic rate of each treatment gives the information that there is a synergistic index between photocatalysis and sonocatalysis.

All-inkjet-printed flexible ZnO micro photodetector for a wearable UV monitoring device

Fabrication of small-sized patterns of inorganic semiconductor onto flexible substrates is a major concern when manufacturing wearable devices for measuring either biometric or environmental parameters. In this study, micro-sized flexible ZnO UV photodetectors have been thoroughly prepared by a facile inkjet printing technology and followed with heat treatments. A simple ink recipe of zinc acetate precursor solution was investigated. It is found that the substrate temperature during zinc precursor ink depositing has significant effects on ZnO pattern shape, film morphology, and crystallization. The device fabricated from the additive manufacturing approach has good bendability, Ohmic contact, short response time as low as 0.3 s, and high on/off ratio of 3525. We observed the sensor’s dependence of response/decay time by the illuminating UV light intensity. The whole process is based on additive manufacturing which has many benefits such as rapid prototyping, saving material, being environmentally friendly, and being capable of creating high-resolution patterns. In addition, this method can be applied to flexible substrates, which makes the device more applicable for applications requiring flexibility such as wearable devices. The proposed all-inkjet-printing approach for a micro-sized ZnO UV photodetector would significantly simplify the fabrication process of micro-sized inorganic semiconductor-based devices. A potential application is real-time monitoring of UV light exposure to warn users about unsafe direct sunlight to implement suitable avoidance solutions.

Investigation of the growth mechanism of the formation of ZnO nanorods by thermal decomposition of zinc acetate and their field emission properties

In the present work, we have explored the growth of ZnO nanorods from a zinc acetate precursor by a thermal decomposition process at 300 °C. Our key observation indicates that a lower heating rate favors the formation of ZnO nanorods while faster heating rates favor the formation of a mixture of ZnO nanorods and nanoparticles. Further, the fabrication of films using dispersions of these nanostructures has been carried out by a low cost spin coating route, which leads to formation of vertically oriented nanorods. The field emission studies of the ZnO film consisting of pure ZnO nanorods show a field enhancement factor of 18 990 while ZnO films containing a mixture of rods and particles show a field enhancement factor in the range of 8571–8829. The field enhancement factor of ZnO nanorods is significantly higher than the previous reports on ZnO nanorods grown by complex physical routes. We have shown a one-step process which results in the formation of high quality ZnO nanorods which is very important for making high end optical and electronic devices.

Nanotextured Surface on Flexographic Printed ZnO Thin Films for Low-Cost Non-Faradaic Biosensors.

In this work, the formation of a nanotextured surface is reported on flexographic printed zinc oxide thin films which provide an excellent platform for low-cost, highly sensitive biosensing applications. The ability to produce nanotextured surfaces using a high-throughput, roll-to-roll production method directly from precursor ink without any complicated processes is commercially attractive for biosensors that are suitable for large-scale screening of diseases at low cost. The zinc oxide thin film was formed by printing a zinc acetate precursor ink solution and annealing at 300 °C. An intricate nanotexturing of the film surface was achieved through 150 °C drying process between multiple prints. These surface nanostructures were found to be in the range of 100 to 700 nm in length with a width of 58 ± 18 nm and a height of between 20 and 60 nm. Such structures significantly increase the surface area to volume ratio of the biosensing material, which is essential to high sensitivity detection of diseases. Nonfaradaic electrochemical impedance spectroscopy measurements were carried out to detect the pp65-antigen of the human cytomegalovirus using the printed device, which has a low limit of detection of 5 pg/mL.

Thin film zinc oxide gas sensor fabricated using near-field electrospray

Near-field electrospray was used to deposit zinc acetate precursor particles over comb electrodes. These particles were heated and oxidized to form a zinc oxide (ZnO) semiconductor at 500 °C. The resulting ZnO thin film on the comb electrode was incorporated into a gas sensor, which was examined using a custom built measurement system. The current that was measured through the electrodes was used to calculate the resistance of the ZnO between the fingers of the comb electrode. The resistance decreased as the sensor was exposed to the target gas of ethanol, while the sensing response (R0/Rg) increased at higher concentrations of target gas. The ZnO sensor displayed high sensitivity because of the small diameters and high specific surface area of the electrospray particles. The ZnO sensors show great promise for use as micro/nano gas sensors as they exhibit high sensitivity, repeatability and stability.

Influence of the precursor anion on the photoluminescence properties of ZnO.

ZnO nanorod arrays were synthesized by hydrothermal method with two different zinc salts as precursors: zinc acetate and zinc nitrate. Different anions in solution distinctly influence the intrinsic defects in ZnO nanostructures, resulting in different photoluminescence properties. The defects induced by precursors were systematically studied by photoluminescence spectroscopy, X-ray photoelectron spectrometer and electron paramagnetic resonance. The results show that zinc acetate precursor mainly introduces zinc vacancy to the lattice while ZnO nanorods obtained from zinc nitrate contain more interstitial oxygen.

A New Precursor Route to Semiconducting Zinc Oxide

We demonstrate a new precursor route toward solution-processed films of the II–VI semiconductor zinc oxide (ZnO). Spray pyrolysis of aqueous solutions of the zinc salt zinc chloride (ZnCl2) onto a substrate heated to at least 250 °C gives films that are insoluble in water, display an absorption edge at 365 nm, and when electrically gated display thin film transistor characteristics similar to ZnO films derived via the established zinc acetate (ZnAc) precursor route; we, therefore, identify it as ZnO. Control experiments attempting spray pyrolysis of aqueous zinc sulfate solutions, and delayed pyrolysis of cold-sprayed and dried ZnCl2 films, do not lead to semiconducting films. Formation of ZnO from an aqueous Zinc salt requires the simultaneous presence of zinc ions, chloride ions, and water, at the time of pyrolysis. We, therefore, suggest that the actual ZnO precursor is the ZnCl x H2O(4– x ) species that forms when ZnCl2 dissolves in water [The Journal of Chemical Physics 39, 3436 (1963)]. The reported process is easy to upscale for large area ZnO coatings, e.g., on window panes for thermal control, as no organic solvent vapors are released.

Effect of calcination temperature on the structural, optical and magnetic properties of pure and Fe-doped ZnO nanoparticles

AbstractIn the present study, pure ZnO and Fe-doped ZnO (Zn0.97Fe0.03O) nanoparticles were synthesized by simple coprecipitation method with zinc acetate, ferric nitrate and sodium hydroxide precursors. Pure ZnO and Fe-doped ZnO were further calcined at 450 °C, 600 °C and 750 °C for 2 h. The structural, morphological and optical properties of the samples were characterized by X-ray diffractometer (XRD), scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) and UV-Vis absorption spectroscopy. The X-ray diffraction studies revealed that the as-synthesized pure and doped ZnO nanoparticles have hexagonal wurtzite structure. The average crystallite size was calculated using Debye-Scherrer’s formula. The particle size was found to be in nano range and increased with an increase in calcination temperature. SEM micrographs confirmed the formation of spherical nanoparticles. Elemental compositions of various elements in pure and doped ZnO nanoparticles were determined by EDX spectroscopy. UV-Vis absorption spectra showed red shift (decrease in band gap) with increasing calcination temperature. Effect of calcination on the magnetic properties of Fe-doped ZnO sample was also studied using vibrating sample magnetometer (VSM). M-H curves at room temperature revealed that coercivity and remanent polarization increase with an increase in calcination temperature from 450 °C to 750 °C, whereas reverse effect was observed for magnetization saturation.

Low-Cost, Large-Area, Facile, and Rapid Fabrication of Aligned ZnO Nanowire Device Arrays.

Well aligned nanowires of ZnO have been made with an electrospinning technique using zinc acetate precursor solutions. Employment of two connected parallel collector plates with a separating gap of 4 cm resulted in a very high degree of nanowire alignment. By adjusting the process parameters, the deposition density of the wires could be controlled. Field effect transistors were prepared by depositing wires between two gold electrodes on top of a heavily doped Si substrate covered with a 300 nm oxide layer. These devices showed good FET characteristics and photosensitivity under UV-illumination. The method provides a fast and scalable fabrication route for functional nanowire arrays with a high degree of alignment and control over nanowire spacing.

Friction and wear behavior of nitrogen-doped ZnO thin films deposited via MOCVD under dry contact

Most researches on doped ZnO thin films are tilted toward their applications in optoelectronics and semiconductor devices. Research on their tribological properties is still unfolding. In this work, nitrogen-doped ZnO thin films were deposited on 304 L stainless steel substrate from a combination of zinc acetate and ammonium acetate precursor by MOCVD technique. Compositional and structural studies of the films were done using Rutherford Backscattering Spectroscopy (RBS) and X-ray Diffraction (XRD). The frictional behavior of the thin film coatings was evaluated using a ball-on-flat configuration in reciprocating sliding under dry contact condition. After friction test, the flat and ball counter-face surfaces were examined to assess the wear dimension and failure mechanism. Both friction behavior and wear (in the ball counter-face) were observed to be dependent on the crystallinity and thickness of the thin film coatings.

Hydrothermal Synthesis and Characterization of ZnO:F Nanorod Structure

F-doped ZnO nanorod structures were synthesized via hydrothermal process with variation of doping content starting from zinc nitrate solution and zinc oxide thin film used as seeding layer. The zinc oxide seeding film was fabricated by spin coating on glass substrate using zinc acetate precursor and annealed at 500 °C for 2 h. Relevant properties of ZnO:F nanorod structures were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX) and UV-VIS spectrophotometer. Corresponding results indicated that ZnO:F nanorod array, grown in (002) plane, has the characteristics of good crystallinity. In addition, this study showed that ZnO:F nanorod with exceptional structure can be obtained by hydrothermal process, operated at proper treatment time, temperature and F-doping content.

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.

Graphene-ZnO nanocomposite for highly efficient photocatalytic degradation of methyl orange dye under solar light irradiation

A facile synthesis of graphene oxide-zinc oxide nanocomposite (GO-ZnO) was performed by using wet chemical method of graphene oxide and zinc acetate precursors. The nanocomposite was characterized and intercalated with Raman spectroscopy, FE-SEM, TEM, SAED and EDAX. The crystalline nature was studied from P-XRD, and surface area of the sample was analyzed by BET. The chemical composition was explained in the light of XPS phenomenon. The photo electron-excitation (PL) studies were conducted for understanding the photocatalytic mechanism, and photocatalytic degradation of methyl orange was studied by using UV-VIS spectrophotometer. We investigated the photocatalytic activity involving GO-ZnO nanocomposite besides checking the re-stability of the composite. Significant high-performance photocatalytic activity of GO-ZnO nanocomposite was exhibited on methyl orange degradation under solar light.