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Cerium oxide (CeO2) thin films were successfully fabricated on glass substrates via spray pyrolysis at 350°C with varying molarities (0.025, 0.05 and 0.1 M). We employed various characterisation techniques to assess how molarity influences these thin films' microstructural, optical, morphological, and surface properties. The as-synthesized samples exhibited a distinct face-centred cubic fluorite structure oriented along the (2 0 0) crystallographic plane. Raman spectroscopy provided insights into imperfections, with the longitudinal optical mode confirming the presence of oxygen vacancies. The peak asymmetry and width in the Raman spectra were associated with the existence of Ce+3 ions and oxygen vacancies. Photoluminescence spectra (PL) illustrated an excitation peak at 400 nm and two emission peaks at 525 nm and 600 nm. Our scanning electron microscopy (SEM) images illustrated how molarity affected the morphologies of the samples, while atomic force microscopy (AFM) allowed us to investigate the film's surface morphologies and roughness values. Transmittance analysis within UV-Vis spectral range indicated that these samples were transparent, with transmittance levels ranging from 20% to 60%. Furthermore, we observed a decrease in the band gap energy (Eg) with increasing molarity. These findings hold significant promise for expanding the applications of cerium oxide in technological devices. [ABSTRACT FROM AUTHOR]

Molybdenum ions with high valence states (Mo6+) can contribute to electrical conductivity and optical transmittance. For this reason, zinc oxide (ZnO) nanorods doped with molybdenum metal were fabricated on a glass substrate by ultrasonic spray pyrolysis method. The doping concentrations were between 0–10 mol%. The crystallographic properties of the resulting ZnO samples were examined by the X‐ray diffraction (XRD) technique. According to the XRD analysis, it was found that the lattice structure of the samples belonged to the hexagonal (wurtzite) unit cell. The XRD results indicated that the crystals grow in the c‐axis (002) direction. The morphological features of the obtained thin films were studied by field emission scanning electron microscopy. The energy‐dispersive X‐ray spectroscopy results displayed that the Mo ions were in the ZnO lattice. Four point probe method was used to determine the electrical conductivity properties of the samples. The 10% mol doped sample has the highest conductivity with values of between 1.58 × 10−9 and 1.58 × 10−6 (ohm‐cm)−1. The optical transmittances of the samples were measured at wavelengths between 300 and 1000 nm. It was observed that the produced films had high optical transparency which was approximately 85%. [ABSTRACT FROM AUTHOR]

[Display omitted] • Using the USP method, Au supported ZnO particles were generated. • Au nanoparticles were dispersed inner and outer portions of the ZnO particles. • The optimal photocatalytic activity occurs with 0.1 mass% Au supported. • The optimal photolysis activity was exhibited at a dose of 10 mg of Ag/ZnO. Environmental pollution by organic dyes used in industry is a serious problem in developing countries. Environmentally friendly treatment methods are being studied because conventional methods require chemical or additional decomposition treatment. In particular, oxidation via a photocatalyst is a promising alternative due to its chemical and physical stabilities and low cost. However, electron-hole recombination limits the photocatalytic activity in semiconductor photocatalysts such as ZnO and TiO 2. This study investigates control of electron-hole recombination of the photocatalyst by loading Au on ZnO (Au/ZnO). Using the Ultrasonic Spray Pyrolysis (USP) method, Au/ZnO particle generation is easily achieved under various conditions. XRD analysis confirms the crystal peaks of ZnO and Au. The EDX mapping and STEM images of the particles show that the Au crystals are well dispersed in the inner and outer portions of ZnO. The photocatalytic decomposition rate of organic dye (Rhodamine-B) is faster than that of ZnO in all Au/ZnO particles, and the best photocatalytic activity occurs in particles with 0.1 mass% Au supported on ZnO particles. In addition, optimal photolysis activity occurs in 100 mL of 5 mg/L RhB aqueous solution and 10 mg dose of Au/ZnO particles. [ABSTRACT FROM AUTHOR]

Dried plum-like ZnO assemblies consisting ZnO nanoparticles were synthesized by an ultrasonic spray pyrolysis method (USP). ZnO assemblies were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), energy-dispersive spectroscopy (EDS) and field-emission transmission electron microscopy (TEM). The results show the size of ZnO assemblies is in the range of 300–870 nm, and that of ZnO nanoparticles is from 33 nm to 39 nm. The microstructure and size of ZnO assemblies were successfully controlled by the concentration of the precursor solution. [ABSTRACT FROM AUTHOR]

The precursor solution of antimony doped tin oxide (ATO) thin film was prepared by sol-gel method using SnCl 4 ·5H 2 O and SbCl 3 as raw materials and anhydrous ethanol as solvent. Then modified carbon nanotubes (CNTs) were added to the precursor solution to form stable precursor suspension. CNTs/ATO composite films were deposited on clean quartz glass by ultrasonic spray pyrolysis method. The films were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, infrared spectroscopy, four-probe tester and thermal testing equipment. The results show that CNTs/ATO composite films can be successfully prepared by ultrasonic spray pyrolysis. The composite films still remained the SnO 2 tetragonal rutile structure. After modification, CNTs were dispersed evenly in the ATO precursor solution and the prepared films were more uniform than films prepared with unmodified CNTs. The lowest square resistance of modified CNTs/ATO film reached 32 Ω/□ and the highest heating temperature reached 362 °C at dry temperature under 220 V. • A novel composite electrothermal film combined with ATO and CNTs by ultrasonic spray pyrolysis method. • The addition of modified CNTs enhanced conductivity and heating temperature of films. • According to the SEM and TEM, CNTs were uniformly distributed throughout the films. • A reasonable explanation for this structure is presented based on the microstructural evidence. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Core-shell Ag/ZnO nanocomposites were synthesized by USP method. • By XRD, Wurtzite (ZnO) and face-centered-cubic (Ag) structures have been identified. • 2-steps route gives consecutive precursor precipitation, improving silver deposition. • Environmental applications of Ag/ZnO synthesized samples are promising. • The optimum Ag+/Zn2+ = 0.2 molar ratio aims the highest photocatalytic activity (93%). Abstract Spherical core-shell Ag/ZnO nanocomposites were synthesised by ultrasonic spray pyrolysis (USP) method from zinc nitrate hexahydrate, Zn(NO 3) 2 ·6H 2 O (ZN) and silver nitrate, AgNO 3 (SN) precursors. Varying solution concentrations and equipment installations (either single − or two-step USP) allowing simultaneous and consecutive precipitation of Ag and ZnO were examined regarding their effect on final particle microstructure and photocatalytic properties. Morphological analyses revealed pure Ag/ZnO core-shell structure where ZnO secondary submicron sized particles formed by primary crystals with the size of 5–20 nm. Depending on the solution concentrations and USP installations, various distributions of Ag in the final microstructure was revealed. Photocatalytic analyses (all samples reached >45% MB degradation) confirm the all Ag/ZnO USP systems viability for environmental applications. The best result (93% of methylene blue (MB) elimination) is obtained for the sample with the maximum available surface, which strongly depends on particle morphology, size, and dispersion. Moreover, all samples synthesised by single step co-precipitation revealed higher dye elimination concerning ones with two steps precipitation due to the favoured distribution of silver nanoparticles in their microstructure and higher specific surface area. Moreover, samples with a uniform and homogeneous Ag distribution exhibited silver-induced enhancement of photocatalytic performance. [ABSTRACT FROM AUTHOR]

Tungsten oxide (WO3) is prepared by a low-temperature ultrasonic spray pyrolysis method in air atmosphere, and it is used as an anode buffer layer (ABL) for organic solar cells (OSCs). The properties of the WO3 transition metal oxide material as well as the mechanism of ultrasonic spray pyrolysis processes are investigated. The results show that the ultrasonic spray pyrolysized WO3 ABL exhibits low roughness, matched energy level, and high conductivity, which results in high charge transport efficiency and suppressive recombination in OSCs. As a result, compared to the OSCs based on vacuum thermal evaporated WO3, a higher power conversion efficiency of 3.63% is reached with low-temperature ultrasonic spray pyrolysized WO3 ABL. Furthermore, the mostly spray-coated OSCs with large area was fabricated, which has a power conversion efficiency of ~1%. This work significantly enhances our understanding of the preparation and application of low temperature-processed WO3, and highlights the potential of large area, all spray coated OSCs for sustainable commercial fabrication. [ABSTRACT FROM AUTHOR]

ZnO is an II–VI compound semiconductor with a wide direct band gap of 3.3 eV at room temperature. Doped with group III elements (B, Al or Ga), it becomes an attractive candidate to replace tin oxide (SnO 2 ) or indium tin oxide (ITO) as transparent conducting electrodes in solar cell devices and flat panel display due to competitive electrical and optical properties. In this work, ZnO and boron doped ZnO (ZnO:B) films have been deposited onto glass substrates at 350 ± 5 °C by a cost-efficient ultrasonic spray pyrolysis technique. The optical, structural, morphological and electrical properties of nanostructure undoped and ZnO:B films have been investigated. Electrical resistivity of films has been analyzed by four-probe technique. Optical properties and thicknesses of the films have been examined in the wavelength range 1200–1600 nm by using spectroscopic ellipsometry (SE) measurements. The optical constants (refractive index ( n ) and extinction coefficient ( k )) and the thicknesses of the films have been fitted according to Cauchy model. The optical method has been used to determine the band gap value of the films. Transmission spectra have been taken by UV spectrophotometer. It is found that both ZnO and ZnO:B films have high average optical transmission (≥80%). X-ray diffraction (XRD) patterns indicate that the obtained ZnO has a hexagonal wurtzite type structure. The morphological properties of the films were studied by atomic force microscopy (AFM). The surface morphology of the nanostructure films is found to depend on the concentration of B. As a result, ZnO:B films are promising contender for their potential use as transparent window layer and electrodes in solar cells. [ABSTRACT FROM AUTHOR]

ZnO nanoparticles were synthesized in a horizontal three zones furnace at 500 °C using different zinc nitrate hexahydrate concentrations (0.01 M, 0.1 M, and 1.0 M) as a reactive precursor solution by air assisted Ultrasonic Spray Pyrolysis (USP) method. The physico-chemical, structural and functional properties of synthesized ZnO nanoparticles have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), high resolution transmission electron microscopy (HRTEM), Brunauer, Emmett and Teller (BET) method, UV–vis spectroscopy and photoluminescence (PL) measurements. Also, the photocatalytic activities of ZnO synthesized from different precursor concentrations were evaluated by removal rate of methyleneblue (MB) under UV irradiation (365 nm) at room temperature. SEM revealed two types of ZnO nanoparticles: a quasi-spherical, desert-rose like shape of the secondary particles, which does not change significantly with the increasing of precursor solution concentration as well as some content of the broken spheres. Increasing the precursor solution concentration leads to the increase in the average size of ZnO secondary particles from 248 ± 73 to 920 ± 190 nm, XRD reveals the similar tendency for the crystallite size which changes from 23 ± 4 to 55 ± 12 nm in the analyzed region. HRTEM implies the secondary particles are with hierarchical structure composed of primary nanosized subunits. The PL spectra imply a typical broad peak of wavelength centered in the visible region exhibiting the corresponding red-shift with the increase of solution concentration: 560, 583 and 586 nm for the 0.01, 0.1 and 1.0 M solution, respectively. The reported results showed the photocatalytic efficiency of ZnO nanoparticles was enhanced by increased precursor concentration. [ABSTRACT FROM AUTHOR]

Highlights: [•] Ag/ZnO nanocomposite catalyst with a single step route is synthesized. [•] Methylene Blue decolorization, degradation and first order kinetics is studied. [•] The highest decolorization and degradation rates are 40% and 27% respectively. [•] The highest degradation rate coefficient is 9×10−3 min−1. [•] Crystallite sizes and atomic fraction difference are important parameters. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ag-supported ZnO particles were generated using the spray pyrolysis method. • Ag/ZnO particles with high efficiency showed twice the photolysis activity of P25. • The generated particles were recovered by gravity sedimentation and reused. • Change of Ag nanoparticles was not observed after the photolysis experiment. Environmental issues caused by the rapid industrialization and urbanization of modern society are a serious problem. For example, conventional wastewater treatment technologies such as adsorption, coagulation, and filtration are expensive and cannot completely treat the discharge of organic pollutants in industrial wastewater. A promising alternative is the decomposition treatment of organic pollutants using an eco-friendly metal oxide photocatalyst. However, the rapid recombination of excited electron-holes limits the photolytic activity of semiconductor photocatalysts. This study investigates the inhibition of electron-hole recombination by supporting Ag nanoparticles on a ZnO photocatalyst. Ag/ZnO particles are generated under various conditions using ultrasonic spray pyrolysis. XRD analysis confirms the presence of Ag and ZnO crystal peaks in the generated particles. EDX mapping and STEM images show that Ag nanoparticles are well dispersed in ZnO. The photolysis rate of organic dye (rhodamine-B) is faster than that of ZnO in all Ag/ZnO particles, and particles with a 0.2 mass% silver nitrate supported on ZnO particles exhibit twice the photolysis activity of P25. Additionally, the optimal photolysis activity in 100 mL of 5 mg/L rhodamine-B aqueous solution with 10 mg of Ag/ZnO particles are confirmed and had excellent persistence and stability even during 7 reuses. [ABSTRACT FROM AUTHOR]

Abstract: The YBCO films were directly deposited on the {110} 〈011〉 textured Ag substrates by ultrasonic spray pyrolysis method. The observed white points in YBCO film by one-step deposition at 900°C consisted in high content of Ag on the surface of this film, which was due to the evaporation and diffusion of Ag atoms at high deposition temperature. While the performance of YBCO films was significantly enhanced using two-step deposition route. A 15cm length of coated YBCO film on {110} 〈011〉 textured Ag tape was prepared by this two-step deposition method, which exhibited a transport J c value of more than 104 A/cm2 (at 77K). [Copyright &y& Elsevier]

Abstract: Superparamagnetic nanocomposite particles prepared by the ultrasonic spray pyrolysis were used in localized hyperthermia therapy, one of the many therapy options for cancer treatment. The primary particle size of the Fe2O3/MgO nanocomposite particles prepared at 800°C was approximately 10nm. The particles show superparamagnetic properties with a blocking temperature of −148°C. Heat generated by an alternating magnetic field of 60Oe increases the tissue temperature to 42.5°C after 125s. [Copyright &y& Elsevier]