• Journal of the Korean Crystal Growth and Crystal Technology
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• v.17 no.1
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• pp.11-17
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• 2007

The spherical NiZn ferrite particles were prepared by ultrasonic spray pyrolysis with mixed solution of aqueous metal nitrates. The NiZn ferrite particle was observed with nano-sized primary particles of about 10 nm or less before annealing which represented as paramagnetic behavior measured at 77 K and room temperature. The typical abnormal growth of primary particles like polyhedral primary particles was observed by annealing at 1273 K with Zn-concentration dependency. The XRD patterns showed good crystallinity of NiZn ferrite powder after annealing. In annealing process, the intra-particle sintering phenomenon was observed and the spherical particle morphology was collapsed at 1673 K. The saturation magnetization of NiZn ferrite powder for each annealing temperature was decreased with measuring temperature of $77{\sim}$300K.

• Journal of the Korean Electrochemical Society
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• v.14 no.2
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• pp.104-109
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• 2011

We fabricated CdSe-sensitized photoelectrochemical solar cell by depositing CdSe nanoparticles on nanoporous $TiO_2$ (np-$TiO_2$) via spray pyrolysis deposition method. By adjusting the amount of CdSe-sensitizer deposited on np-$TiO_2$, we can fabricate an efficient CdSe-sensitized solar cell (${\eta}$ = 3.0% under 1 sun irradiation) in polysulfide liquid electrolyte.

• Journal of Sensor Science and Technology
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• v.14 no.5
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• pp.362-367
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• 2005

ZnO films were deposited on MgO substrates (ZnO/MgO) by ultrasonic spray pyrolysis. Substrate temperature varied from $250^{\circ}C$ to $350^{\circ}C$. The crystallographic properties and surface morphologies of the ZnO/MgO films were studied by X-ray diffraction and scanning electron microscopy. The properties of photoluminescence (PL) for the films were investigated by dependence of PL spectra on the substrate temperature and the annealing temperature. The ZnO/MgO films prepared at $350^{\circ}C$ showed the strongest Ultraviolet light emission peak at 18 K and 300 K among the films in this study. The annealing process increases the visible light emission, which is due to the increased oxygen vacancies.

• Korean Journal of Materials Research
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• v.15 no.3
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• pp.209-215
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• 2005

Titanium dioxide films $(TiO_2)$ doped cobalt transition metal were prepared on titanium metal by water spray pyrolysis technique. Micro-morphology, crystalline structure, chemical composition and binding state of sample groups were evaluated using field emission scanning microscope(FE-SEM), X-ray diffractometer(XRD), Raman spectrometer, X-ray photoelectron spectrometer(XPS). $TiO_2$ films of rutile structure were predominately formed on all sample groups and $Ti_2O_3$ oxide was coexisted on the surface of cobalt doped-sample groups. The optical absorption peaks measured by using UV-VIS-NIR spectrophotometer were observed at specific wavelength region in sample groups doped cobalt ion. This result could be analyzed by introducing crystal field theory.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.1001-1004
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• 2003

We applied the spray pyrolysis technique to prepare fine $YBO_{3}$:Tb particles with high photoluminescence, which could be used in the plasma display device as a green phosphor. Several preparation conditions were investigated in order to tail the vacuum ultraviolet characteristics of $YBO_{3}$:Tb particles when they were prepared by the spray pyrolysis. As a result, the optimized $YBO_{3}$:Tb particles showed the high photoluminescence intensity as well as fine size in comparison with the commercial one.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.1
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• pp.58-63
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• 2006

In this Paper, ZnO films mixed with iron oxide were prepared by an ultrasonic spray pyrolysis method. The chemical composition and structural properties as a function of the Fe atomic ratio in the deposition solution were studied. Zinc acetate and ferrous chloride were used as precursors of Zn and Fe, respectively. Fe atomic ratio to Zn varied from 0.15 to 10.0. Substrate temperature was fixed at $250^{\circ}C$. The crystallographic properties and surface morphologies of the films were studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. Electron probe X-ray microanalysis (EPMA) and X-ray photoelectron spectroscopy (XPS) were carried out to analyse the chemical composition and state of Zn and Fe atoms.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.11a
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• pp.195-198
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• 2004

ZnO films were Prepared by ultrasonic spray Pyrolysis on MgO substrates. The surface morphology and crystallinity were observed as a function of substrate temperature by SEM and XRD, respectively. PL properties of the ZnO films were studied by using Cd-He laser. UV light around 3.37 eV was pronounced in the PL spectra. The origin of the PL peak was discussed.

• Journal of Sensor Science and Technology
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• v.16 no.4
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• pp.307-312
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• 2007

The films of Er-doped ZnO (ZnO:Er) were prepared onto MgO wafers by ultrasonic spray pyrolysis at $550^{\circ}C$. The concentration of Er in the deposition source varied from 0.5 wt% to 3.0 wt%. The crystallographic properties and surface morphologies of the films were investigated by X-ray diffraction (XRD) and scanning electron microscope (SEM), respectively. The properties of photoluminescence (PL) for the films were investigated by dependence of PL spectra on the Er concentration in the films. The films were grown as polycrystalline with a dominant direction of [002]. The grain size of the films were reduced by Er-doping. Er-doping enhanced the ultraviolet emission of ZnO:Er films. The ZnO:Er films prepared with the deposition source of 2.0 wt% Er showed the strongest ultraviolet light emission peak among the films in this study.

• Bulletin of the Korean Chemical Society
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• v.23 no.8
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• pp.1127-1134
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• 2002

Fine ceramic particles of zirconia toughened alumina (ZTA), titania toughened alumina (TTA), and zirconia-titania toughened alumina (ZTTA) have been synthesized by ultrasonic spray pyrolysis (USP) at various temperatures from starting salt solutio ns of various compositions aiming for the development of catalytic material. These particles were characterized for properties such as shape, size and size distribution, diffraction pattern, and chemical and phase composition of elements by scanning electron microscopy (SEM), particle size analyzer (PSA), x-ray diffraction (XRD), and inductively coupled plasma-atomic emission spectroscopy (ICP-AES). Chemical compositions and sizes of ceramic composites have been controled by the stoichiometry of salt solutions and the flow rate of spraying solutions. The optimum experimental conditions for the various composite particle syntheses have been proposed.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1300-1302
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• 2009

Transparent $Zn_2SiO_4:Mn^{2+}$ film has been synthesized by spray pyrolysis with various spraying conditions. It illuminates an efficient green emission with the relative emission intensity about 45% under 147nm excitation of a commercial powder phosphor. Additionally, the zinc precursors and additives play a key factor both controlling luminous efficiency and transparency.