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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]

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]

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]