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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]

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]