Methodology for the Selection of Technological Modes for the Synthesis of Transparent Conducting Oxides with Desired Properties

Transparent conducting oxides (TCOs) are widely used as a transparent electrode in various fields of opto-and semiconductor electronics. The main materials used today are indium-tin oxide, tin-antimony oxide and zinc-aluminum oxide. The authors have developed and improved the spray-pyrolysis method, which is one of the most promising methods of implementation in production. In this work, the study of tin dioxide doped with antimony coatings and the development of a methodology for the controlled synthesis of TCO, taking into account the effect of technological modes of deposition on the TCO parameters. The results of the performed studies contribute to the development of an automated technology for the synthesis of transparent conducting oxides with desired properties.

Mixed Oxides NiO/ZnO/Al2O3 Synthesized in a Single Step via Ultrasonic Spray Pyrolysis (USP) Method

Mixed oxides have received remarkable attention due to the many opportunities to adjust their interesting structural, electrical, catalytic properties, leading to a better, more useful performance compared to the basic metal oxides. In this study, mixed oxides NiO/ZnO/Al2O3 were synthesized in a single step via the ultrasonic spray pyrolysis method using nitrate salts, and the temperature effects of the process were investigated (400, 600, 800 °C). The synthesized samples were characterized by means of scanning electron microscopy, energy-dispersive spectroscopy, X-ray diffraction and Raman spectroscopy analyses. The results showed Al2O3, NiO–Al2O3 and ZnO–Al2O3 systems with spinel phases. Furthermore, the Raman peaks supported the coexistence of oxide phases, which strongly impact the overall properties of nanocomposite.

Ion-doped mesoporous bioactive glass: preparation, characterization, and applications using the spray pyrolysis method

Bioactive glasses (BAG) are one type of biomaterial that is used in dentistry and orthopedics to repair or replace damaged bone. The spray pyrolysis process is low-cost and one of the most common ways for producing porous films and films with high-density packing and particle homogeneity.

Influence of the Distance Between Nozzle and Substrate on Structural, Photoluminescence, and Detector Characteristics of p-NiO/n-Si Hetero-Junction Deposited by Spray Pyrolysis Method

In the present investigation, p-NiO has been deposited on n-Si (100) substrate by the spray pyrolysis method. The effect of the distance between the substrate and the nozzle on the structural, photoluminescence, and detection properties has been well inspected. XRD analysis proved the polycrystalline system with a cubic structure for NiO. The elemental analysis confirmed the existence of Ni, O, and Si materials without any impurities. The FESEM analysis showed nano and micro particles distributed on the Si layer, the micro particles have porous like structures which play a significant role as photons guider. The photoluminescence measurement depicted three main peaks at the UV and visible regions of the electromagnetic spectrum which are related to near band edge emission and defects within the crystal, respectively. I-V characteristics revealed good conductivity under UV illumination, and the highest current was recorded by a sample when the distance between the nozzle and the substrate is 25 cm. The responsivity elucidated a high value at UV region with 6.5 mA/W, and the current-time properties demonstrated good reproducibility, high stability and photoresponse, and rapid response and recovery times of 0.375 and 0.791 s, respectively at a lower bias voltage of 1.5 Volt under UV photons source.

Investigation of the Temperature on the Thin Layers of Cobalt Oxide Produced by the Spray Pyrolysis Method Using a Solar Oven

Thin films of cobalt oxide (Co3O4) were prepared on glass substrates by the spray pyrolysis method using a solar concentrator (oven) manufactured in our laboratory. We used different processing temperatures (300° C, 350° C and 400° C). The structural, optical and electrical properties of the different samples were analyzed by X-ray diffraction (XRD), UV-Visible spectroscopy and the Hall effect measurement system. X-ray diffraction observations revealed that cubic crystals are created in all films produced, and the film structure is that of a single phase created with preferential orientation along the (311) axis in films at low temperatures, and the axis (111) for high temperatures. The grain sizes of our products vary between (22.62nm and 66.19nm), depending on the processing temperature. The optical band gap of the crystals obtained was measured. The results of the optical forbidden bands of the crystals obtained, indicated two bands of the values for each element (Eg1 and Eg2). We observed that the values of the effective optical forbidden bands increase by 2.547eV and 3.0731eV with the increase in the production temperature., In addition the film produced experiences a decrease in the Urbach parameters which vary between 162.20meV and 360.81meV depending on the increase in production temperatures. Finally, the films produced have electrical conductivity values of (1.090 [(Ω.cm)−1] to 1.853 [(Ω.cm)−1] and electrical resistivity values of 1.431 (Ω.cm) at 1.853 (Ω.cm), depending on the variation in the production temperature.

Enhanced Electrical Properties of Alkali-Doped ZnO Thin Films with Chemical Process

Doped ZnO are among the most attractive transparent conductive oxides for solar cells because they are relatively cheap, can be textured for light trapping, and readily produced for large-scale coatings. Here, we focus on the development of alternative Na and K-doped ZnO prepared by an easy low-cost spray pyrolysis method for conducting oxide application. To enhance the electrical properties of zinc oxide, alkali-doped Zn1−x MxO (x = 0.03) solid solutions were investigated. The resulting layers crystallize in a single hexagonal phase of wurtzite structure with preferred c-axis orientation along a (002) crystal plane. Dense, well attached to the substrate, homogeneous and highly transparent layers were obtained with great optical transmittance higher than 80%. The optical energy band gap of doped ZnO films increase from 3.27 to 3.29 eV by doping with Na and K, respectively. The electrical resistivity of the undoped ZnO could be decreased from 1.03 × 10−1 Ω.cm to 5.64 × 10−2 Ω.cm (K-doped) and 3.18 × 10−2 (Na-doped), respectively. Lastly, the carrier concentrations increased from 5.17 × 1017 (undoped ZnO) to 1 × 1018 (doped ZnO).

Preparation of hollow spherical particles of ferrite strontium SrFe₁₂O₁₉ by spray-pyrolysis

The article presents the synthesis of hollow nanostructured microspheres of ferrite strontium by spray-pyrolysis. The phase composition, morphology, dispersion of the microspheres obtained and the effect of synthesis parameters to the morphology and the dispersion of the material obtained are investigated. It has been established that in the process of synthesis by spray-pyrolysis method, hollow nanostructured microspheres are formed with dimensions in the range of 0,5‒10,0 μm, the thickness of the microspheres of the microspheres is about 100 nm. Microspheres consist of particles of 10‒20 nm. Ill. 4. Ref. 12. Tab. 1.

Study on Low Temperature Conduction Mechanism of Al Doped ZnO/SiO2/ P-Si Heterojunction

The 3 at% Al doped ZnO thin films were deposited on p-Si substrate with a native SiO2 layer by spray pyrolysis method. Low temperature conduction behaviors were studied by analysis of impedance spectroscopy and low temperature ac conductivity. The results of impedance spectroscopy showed that the grain boundaries contributed to the resistivity of Al doped ZnO/SiO2/p-Si heterojunction. The calculated activation energy was 0.073 eV for grain boundaries. The equivalent circuit to demonstrate the electrical properties of Al doped ZnO/SiO2/p-Si heterojunction was a series connection of two parallel combination circuits of a resistor and a universal capacitor. Low temperature ac conductivity measurements indicated that the conductivity increased with temperature. Low temperature conductivity mechanism was electron conductivity, and the activation energy was 0.086 eV.