Effect of Atmosphere on Zinc Oxide Crystal Growth by Electric Current Heating with Au Catalyst

2006 ◽  
Vol 11-12 ◽  
pp. 269-272 ◽  
Author(s):  
Kenichi Minato ◽  
Tomoichiro Okamoto ◽  
Masasuke Takata
Keyword(s):  
Zinc Oxide ◽  
Crystal Growth ◽  
Electric Current ◽  
Room Temperature ◽  
Visible Emission ◽  
Au Catalyst ◽  
Uv Emission ◽  
Oxide Crystal ◽  
Growth Method ◽  
Zno Crystal

We developed a new zinc oxide (ZnO) crystal growth method using Au combined with electric current heating. Au paste was placed on a ZnO ceramic bar. When a certain current flowed through the bar, the paste melted on the bar. Then crystals grew on the molten Au surface immediately. The shape of the crystals depended on the atmosphere during the growth. The whiskers with spherical top and the crystals consisting of a hexangular pyramidal base and needle head were grown on Au in air and Ar atmosphere, respectively. From cathodoluminescence at room temperature, the weak ultraviolet (UV) emission at approximately 3.2 eV and the strong visible emission at approximately 2.3 eV were observed from the whisker grown in air. The UV emission at approximately 3.3 eV dominated a spectrum from the pyramidal crystal grown in Ar atmosphere.

MORPHOLOGY CONTROLLING AND OPTICAL CHARACTERIZATION OF ZnO NANOMATERIALS

2006 ◽  
Vol 20 (25n27) ◽  
pp. 3635-3639
Author(s):  
YUZHEN LV ◽  
CHUNPING LI ◽  
PING CHE ◽  
LIN GUO ◽  
HUIBIN XU
Keyword(s):  
Room Temperature ◽  
Optical Characterization ◽  
Visible Emission ◽  
Ultraviolet Emission ◽  
Synthetic Process ◽  
Uv Emission ◽  
Zno Nanomaterials ◽  
Solution Route ◽  
Pl Spectrum

Wurtzite ZnO nanomaterials including nanoparticles, nanocolumns and nanorods were successfully synthesized by a solution route. Concentrations of modifying reagent and differences of solvent employed in the synthetic process can effectively adjust the morphologies of the as-grown products. Photoluminescence measurements of the ZnO nanocolumns and nanorods have been carried out at room temperature. A sharp Ultraviolet emission at 386 nm and a weak visible emission centered at 515 nm were observed in the PL spectrum of the nanocolumns, while a UV emission of the nanorods was observed at 377 nm.

Phase relations and flux research for zinc oxide crystal growth in the ZnO–Na2O–P2O5 system

2008 ◽  
Vol 465 (1-2) ◽  
pp. 436-441 ◽  
Author(s):  
L.N. Ji ◽  
J.B. Li ◽  
J. Luo ◽  
J.K. Liang ◽  
J.Y. Zhang ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Crystal Growth ◽  
Phase Relations ◽  
Oxide Crystal ◽  
P2o5 System

scholarly journals Direction-specific interaction forces underlying zinc oxide crystal growth by oriented attachment

2017 ◽  
Vol 8 (1) ◽  
Author(s):  
X. Zhang ◽  
Z. Shen ◽  
J. Liu ◽  
S. N. Kerisit ◽  
M. E. Bowden ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Crystal Growth ◽  
Specific Interaction ◽  
Oriented Attachment ◽  
Interaction Forces ◽  
Oxide Crystal

Well-Controlled Crystal Growth of Zinc Oxide Films on Plastics at Room Temperature Using 2D Nanosheet Seed Layer

2009 ◽  
Vol 113 (44) ◽  
pp. 19096-19101 ◽  
Author(s):  
Tatsuo Shibata ◽  
Tsuyoshi Ohnishi ◽  
Isao Sakaguchi ◽  
Minoru Osada ◽  
Kazunori Takada ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Crystal Growth ◽  
Seed Layer ◽  
Room Temperature ◽  
Oxide Films ◽  
Zinc Oxide Films

The Effect of Green Body Pressure, Sintering Time and Electric Current on ZnO Crystal Growth by Electric Current Heating Method

2020 ◽  
Vol 981 ◽  
pp. 3-10
Author(s):  
Aw Fong Ling ◽  
Ali Shaitir ◽  
Ari Legowo ◽  
Agus Geter Edy Sutjipto
Keyword(s):  
Crystal Growth ◽  
Powder Metallurgy ◽  
Electric Current ◽  
High Purity ◽  
Emission Measurement ◽  
Green Body ◽  
Sintering Time ◽  
Powder Metallurgy Process ◽  
Zno Crystal ◽  
Metallurgy Process

There are three objectives to be achieved in this research which include to synthesis high purity ZnO pellets with different sintering time and green body pressure by using powder metallurgy process, the growth of ZnO crystal on ceramic bar by applying different current when conducting electric current heating (ECH) method and the characterization of ZnO crystal growth. In this research, high purity of ZnO powder is grinded and compressed at 3.5 tons, 4.5 tons and 5.5 tons to fabricate ZnO green pellets. Then, the ZnO green pellets are sintered for 3 hours and 5 hours. Next, the pellets are cut into bars and apply ECH method. The amount of current applied for the crystal growth are 2A and 3A. Finally, the crystal grown on the ZnO ceramic bar is characterized using X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Ultraviolet-visible Spectroscopy (UV-Vis) and Photoluminescence Spectroscopy (PL). High purity ceramic pellets are successfully synthesis by powder metallurgy process. By conducting ECH method, crystal are grown on the surface of ceramic bar. Most crystal structure found in ZnO ceramic bar is needle-liked rod structure which is hexagonally formed by many nanorod. The crystal grown in (100) orientation with the crystalline size of from 57.80 nm to 100.31 nm. The band gap energy obtained from UV-Vis were found between 3.2 eV to 3.4 eV which is nearly similar to the theoretical value of 3.37 eV. Lastly, PL emission measurement give the peak that range between 579 nm to 587 nm which indicate that the sample exhibit yellow colour. Among three different pressure applied, 4.5 tons gives the lowest emission energy. It is considered as the critical pressure in the synthesis of ZnO crystal. The intensity of PL is considered inversely proportional to intensity of XRD in [100] direction. Pressing pressure doesn’t show significant effect on the crystal growth of ZnO but current applied during ECH method and sintering time do give effect on UV-Vis absorption spectra and XRD result respectively.

High Photoluminescence Spectroscopy on High Purity ZnO Crystal Growth by Electric Current Heating Method

2020 ◽  
Vol 981 ◽  
pp. 45-50
Author(s):  
Agus Geter Edy Sutjipto ◽  
Heng Hooi Chi ◽  
Ali Shaitir ◽  
Ari Legowo
Keyword(s):  
Crystal Growth ◽  
Room Temperature ◽  
Low Cost ◽  
Visible Region ◽  
Pressing Pressure ◽  
Sem Images ◽  
Heating Method ◽  
Sintering Time ◽  
Zno Crystal ◽  
Zno Ceramics

The fabrication technique applied in this research to grow ZnO crystal is known as ECH method. It is a preferred method due to its low cost, simplicity in operating and low growth temperature. However the condition of ECH method to produce the optimum crystal growth has not been studied further. The objectives of this research are to synthesize ZnO ceramic pellets, to produce ZnO micro/nanostrcutures on ZnO ceramics bar by ECH method, as well as to characterize and analyze structural, morphological, and optical properties of ZnO crystals grown. ZnO pellets were formed by pressed at 3, 4, 5 tons and sintered at 1,100 °C in air for 4 and 72 hours. ZnO ceramic bar was joule heated by direct current of 2 A and 3 A. The result is the grain size of ZnO pellets increased with increasing sintering time and pressing pressure. XRD results indicated mostly crystal prefer to grow along (100) orientation. SEM images showed crystals grown was in a variety of shapes and sizes. PL measurements at room temperature revealed high intensity peak of in visible region in which yellow-level emission was observed from ZnO crystals grown.

Phase relations and flux research for zinc oxide crystal growth in the ZnO–K2O–P2O5 system

2009 ◽  
Vol 470 (1-2) ◽  
pp. 336-339 ◽  
Author(s):  
L.N. Ji ◽  
J.B. Li ◽  
J. Luo ◽  
J.K. Liang ◽  
Y.H. Liu ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Crystal Growth ◽  
Phase Relations ◽  
Oxide Crystal ◽  
P2o5 System

Single Crystal Growth of High-Pressure Phases of Ice and Salt Hydrate Far Below the Original Melting Point by Mixing Alcohol: Crystal Structure Determination of Magnesium Chloride Heptahydrate

2020 ◽  
Author(s):  
Keishiro Yamashita ◽  
Kazuki Komatsu ◽  
Hiroyuki Kagi
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
Crystal Growth ◽  
Single Crystal ◽  
Room Temperature ◽  
Growth Technique ◽  
Salt Hydrate ◽  
X Ray

An crystal-growth technique for single crystal x-ray structure analysis of high-pressure forms of hydrogen-bonded crystals is proposed. We used alcohol mixture (methanol: ethanol = 4:1 in volumetric ratio), which is a widely used pressure transmitting medium, inhibiting the nucleation and growth of unwanted crystals. In this paper, two kinds of single crystals which have not been obtained using a conventional experimental technique were obtained using this technique: ice VI at 1.99 GPa and MgCl<sub>2</sub>·7H<sub>2</sub>O at 2.50 GPa at room temperature. Here we first report the crystal structure of MgCl2·7H2O. This technique simultaneously meets the requirement of hydrostaticity for high-pressure experiments and has feasibility for further in-situ measurements.

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