Journal of Powder Materials

Hae-Jin Hwang

3 Articles

Synthesis and Characterization of Y-doped SrTiO₃ Powder by Pechini Method: Mi-Young Yoon, R.H. Song, D.R. Shin, Hae-Jin Hwang; J Korean Powder Metall Inst. 2010;17(1):59-64.; DOI: https://doi.org/10.4150/KPMI.2010.17.1.059

27 View
0 Download
3 Citations

8 mol% Y-doped SrTiO_3 powder was synthesized by Pechini method from titanium isopropoxide, strontium nitrate, yttrium nitrate, citric acid and ethylene glycol. A Y_2Ti_2O_7 pyrochlore phase-free perovskite powder was obtained by calcining a polymeric resin, which was prepared from a precursor solution, at 500°C in an air atmosphere. Low temperature calcination could lead to a fine-grained microstructure. In the case of a solid-state reaction, an extended heat-treatment at high temperature in a reduced atmosphere needed to obtain a single phase perovskite SrTiO_3.

Citations

Citations to this article as recorded by

Characteristics of Sr0.92Y0.08TiO3-δ Anode in Humidified MethaneFuel for Intermediate Temperature Solid Oxide Fuel Cells
Eun Kyung Park, Jeong Woo Yun
Journal of Electrochemical Science and Technology.2016; 7(1): 33. CrossRef
Characteristics of Sr0.92Y0.08TiO3-δAnode in Humidified MethaneFuel for Intermediate Temperature Solid Oxide Fuel Cells
Eun Kyung Park, Jeong Woo Yun
Journal of Electrochemical Science and Technology.2016; 7(1): 33. CrossRef
Synthesis of NiTi Alloy Powder by the Reaction of NiO-TiH2 Mixing Powders
Ki Cheol Jeon, Han-Eol Lee, Da-Mi Yim, Sung-Tag Oh
journal of Korean Powder Metallurgy Institute.1970; 22(4): 266. CrossRef

Titanate Nanotube Formation and Nanostructure Development from the Reaction of TiO₂ Nanopowder and Alkalihydroxide: Eun-Ju Jin, Doh-Hyung Riu, Seung-Hun Huh, Chang-Yeoul Kim, Hae-Jin Hwang; J Korean Powder Metall Inst. 2008;15(2):125-135.; DOI: https://doi.org/10.4150/KPMI.2008.15.2.125

16 View
0 Download
1 Citations

Abstract PDF

[ TiO_2 ] nanotubes for photocatalytic application have been synthesized by hydrothermal method. TiO_2 nanotubes are formed by washing process after reaction in alkalic solution. Nanotubes with different morphology have been fabricated by changing NaOH concentration, temperature and time. TiO_2 nanoparticles were treated inside NaOH aqueous solution in a Teflon vessel at 110°C for 20 h, after which they were washed with HCl aqueous solution and deionized water. Nanotube with the most perfect morphology was formed from 0.1 N HCl washing treatment. TiO_2 nanotube was also obtained when the precursor was washed with other washing solutions such as NH_4OH, NaCl, K_2SO_4, and Na_2SO_3. Therefore, it was suggested that Na+ ion combined inside the precursor compound slowly comes out from the structure, leaving nanosheet morphology of TiO_2 compounds, which in turn become the nanotube in the presence of hydroxyl ion. To stabilize the sheet morphology, the different type of washing treatment solution might be considered such as amine class compounds.

Citations

Citations to this article as recorded by

Coating Property of Hybrid Structured Photo-Electrode to Increase Dye-Sensitized Solar Cells Efficiency
Min-Hee Kim, Hyung-Woo Lee, Young-Keun Jeong
Journal of Korean Powder Metallurgy Institute.2010; 17(6): 449. CrossRef

Platinum Nano-Dispersion via In Situ Processing - Preparation and catalytic Property of Porous CaZrO_3/MgO/Pt Nanocomposite: Yoshikazu, Hae-Jin Hwang, Kondo Naoki, Ohji Tatsuki; J Korean Powder Metall Inst. 2001;8(3):163-167.

5 View
0 Download

Abstract PDF: A bulk porous CaZrO_3/MgO composite with plantinum nano-dispersion was synthesized in air atmosphere through the combination of several in situ reactions, including the pyrolysis of PtO_2. A mixture of CaMg(CO_3)_2(dolomite), ZrO_2, PtO_2 and LiF (0.5 wt%, as an additive) was cold isostatically pressed at 200 MPa and sintered at 1100°C for 2 h. The porous CaZrO_3/MgO/Pt composite (CaZrO_3/MgO : Pt=99 : 1 in volume) had a uniformly open-porous structure (porosity: 56%) with three-dimensional (3-D) network and a narrow pore-size distribution, similarly to the porous CaZrO_3/MgO composites reported before. Catalytic Properties (viz., NO direct decomposition and NO reduction by C_2H_4) of the CaZrO_3/MgO/Pt composite were investigated up to 900°C. In the absence of oxygen, the NO conversion rate reached ~52% for the direct decomposition and ~100% for the reduction by C_2H_4, respectively. The results suggest the possibility of the porous composite as a multifunctional filter, i.e., simultaneous hot gas-filtering and de-NO_x in one component.

Author index