• Title/Summary/Keyword: spray pyrolysis

Search Result 349, Processing Time 0.034 seconds

Synthesis of Homogeneous La0.8Sr0.2CrO3 Powders Using an Ultrasonic Spray Pyrolysis Method

  • Kim, Chang-Sam;Hwang, Seong-Ik;Kim, Shin-Woo
    • Journal of the Korean Ceramic Society
    • /
    • v.44 no.5 s.300
    • /
    • pp.148-150
    • /
    • 2007
  • A process to synthesize $La_{0.8}Sr_{0.2}CrO_3$ (LSC), which is a promising material for use as a separator in a soild oxide fuel cell, is investigated in this study. LSC powders without secondary Phases could be synthesized with ultrasonic spray pyrolysis and a heat treatment at $1200^{\circ}C$ for 20 h; however, it showed an average diameter of $0.6{\mu}m$ with a wide particle size distribution. On the other hand, LSC powders synthesized with spray pyrolysis at $800^{\circ}C$, heat-treated at $900^{\circ}C$ for 5 h, ball-milled and finally heat-treated again at $1200^{\circ}C$ for 20 h showed a smaller average diameter of $0.3{\mu}m$ and narrower size distribution. Very few particles above $0.5{\mu}m$ were found. Thus, a proper combination of the heat treatment and milling process after spray pyrolysis it determined to be very important in synthesizing fine and uniform LSC perovskite powders.

Synthesis of Ceria Nanosphere by Ultrasonic Spray Pyrolysis

  • Kim, Jong-Young;Kim, Ung-Soo;Cho, Woo-Seok
    • Journal of the Korean Ceramic Society
    • /
    • v.46 no.3
    • /
    • pp.249-252
    • /
    • 2009
  • Nanocrystalline ceria particles were prepared by using the ultrasonic spray pyrolysis method. The prepared ceria particles were found to be spherical and non-agglomerated by the SEM and TEM analyses. It was found that carrier gas influences the size and morphology. It was found that the air stream of carrier gas results in porous agglomerated structure of ceria abrasives, whereas solid nano-sphere can be obtained in a more oxidizing atmosphere.

Thermal degradation properties of blue emitting phosphor particles prepared by the spray pyrolysis for PDP (분무열분해공정에서 제조된 PDP용 청색형광체의 열화특성)

  • Kang, Yun-Chan;Lee, Dong-Youl;Park, Hee-Dong
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2002.07b
    • /
    • pp.1060-1062
    • /
    • 2002
  • Spherical and dense BAM phosphor particles were prepared by spray pyrolysis. The key idea of dense BAM particles is to lead gelation in droplets, which was successfully achieved by using the aluminum polycation as the precursor solution for the spray pyrolysis. The BAM phosphor particles prepared by spraying the aluminum polycation solution have completely spherical shape and dense structure. When directly applied to make phosphor film on the glass by the screen-printing method, the prepared spherical BAM phosphor particles showed better packing density and surface morphology than that of commercial one, which has irregular shape and large particle size. It was also found that the thermal degradation in the photoluminescence intensity for dense and spherical BAM particles was less than that of commercial one.

  • PDF

Preparation of Ultrafine Barium Titanate Powder by Slurry Spray Pyrolysis (슬러리 분무열분해에 의한 초미립 티탄산 바륨 분말 제조)

  • Lee, Jong-Ho;Hur, Kang-Heon;Lee, Jung-Soo
    • Journal of the Korean Ceramic Society
    • /
    • v.46 no.2
    • /
    • pp.137-145
    • /
    • 2009
  • A remarkable improvement of the productivity in barium titanate by slurry spray pyrolysis process was realized by supplying solid source slurry into the rector. The produced barium titanate powders showed uniform powder properties, and reproducibility with higher tetragonality in the range of 80$\sim$200 nm, case by case. The secondary calcination experiments of the as-prepared powders by spray pyrolysis revealed that the powders as-prepared over 700$^{\circ}C$ showed perfectly different behavior with the lower temperature's ones and the solid state reaction’s case. The result was discussed in terms of the reaction mechanism based on the activation energy analysis.

Synethisis of fine BSCCO precursor powder by spray pyrolysis (분무 열분해에 의한 미세 BSCCO 전구체 분말의 합성)

  • 김성환;유재무;고재웅;김영국;박성창
    • Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
    • /
    • 2003.10a
    • /
    • pp.99-102
    • /
    • 2003
  • Many researches on synthesis process for BSCCO precursor powders have been developed for high J$_{c}$ BSCCO-2223/Ag tape. Spray pyrolysis method for fabrication of precursor powder has many advantages, such as high purity, fine particle size of BSCCO precursor powder. Fine, spherical powders were prepared by ultrasonic spray pyrolysis from the aqueous solution of metal nitrates. BSCCO precursor powders were synthesized with 0.1 M concentration and heat treatment conditions. Average particle size for spray pyrolysis powders was 1.5 ~ 3 ${\mu}{\textrm}{m}$. BSCCO -2223/Ag tape was prepared by PIT method and followed by various sintering conditions. The critical current density of BSCCO-2223/Ag tape sintered in low oxygen partial pressure was ~ 23 kAcm$^{-2}$.

  • PDF

The Study of nc-ZnO/ZnO Field-effect Transistors Fabricated by Spray-pyrolysis Process (스프레이 공정을 이용한 nc-ZnO/ZnO 전계효과트랜지스터 제작 및 특성 분석)

  • Cho, Junhee
    • Journal of the Semiconductor & Display Technology
    • /
    • v.21 no.3
    • /
    • pp.22-25
    • /
    • 2022
  • Metal oxide semiconductor (MOS) based on spray-pyrolysis deposition technique has attracted large attention due to simple and low-cost processibility while preserving their intrinsic optical and electrical characteristics. However, their high process temperature limits practical applications. Here, we demonstrated the nc-ZnO/ZnO field-effect transistors (FETs) via spray-pyrolysis as incorporating ZnO nanocrystalline nanoparticles into typical ZnO precursor. The nc-ZnO/ZnO FETs exhibit good quality of electrical properties. Our experiments reveal that nc-ZnO in active layer enhance electrical characteristics.

Morphological and Electrical Characteristics of nc-ZnO/ZnO Thin Films Fabricated by Spray-pyrolysis for Field-effect Transistor Application (전계효과트랜지스터 기반 반도체 소자 응용을 위한 스프레이 공정을 이용한 nc-ZnO/ZnO 박막 제작 및 특성 분석)

  • Cho, Junhee
    • Journal of the Semiconductor & Display Technology
    • /
    • v.20 no.4
    • /
    • pp.1-5
    • /
    • 2021
  • Field-effect transistors based on solution-processed metal oxide semiconductors has attracted huge attention due to their intrinsic characteristics of optical and electrical characteristics with benefits of simple and low-cost process. Especially, spray-pyrolysis has shown excellent device performance which compatible to vacuum-processed Field-effect transistors. However, the high annealing temperature for crystallization of MOS and narrow range of precursors has impeded the progress of the technology. Here, we demonstrated the nc-ZnO/ZnO films performed by spray-pyrolysis with incorporating ZnO nanoparticles into typical ZnO precursor. The films exhibit preserving morphological properties of poly-crystalline ZnO and enhanced electrical characteristics with potential for low-temperature processability. The influence of nanoparticles within the film was also researched for realizing ZnO films providing good quality of performance.

The Instability Behaviors of Spray-pyrolysis Processed nc-ZnO/ZnO Field-effect Transistors Under Illumination (스프레이 공정을 이용한 nc-ZnO/ZnO 전계효과트랜지스터의 광학적 노출에 대한 열화 현상 분석)

  • Junhee Cho
    • Journal of the Semiconductor & Display Technology
    • /
    • v.22 no.1
    • /
    • pp.78-82
    • /
    • 2023
  • Metal oxide semiconductor (MOS) adapting spray-pyrolysis deposition technique has drawn large attention based on their high quality of intrinsic and electrical properties in addition to simple and low-cost processibility. To fully utilize the merits of MOS field-effect transistors (FETs) , transparency, it is important to understand the instability behaviors of FETs under illumination. Here, we studied the photo-induced properties of nc-ZnO/ZnO field-effect transistors (FETs) based on spray-pyrolysis under illumination which incorporating ZnO nanocrystalline nanoparticles into typical ZnO precursor. Our experiments reveal that nc-ZnO in active layer suppressed the light instabilities of FETs.

  • PDF