Abstract
Abstract Transparent barium titanoborate glass-ceramics bearing TiO<inf>2</inf> (anantase) nanocrystals were prepared by the conventional melt-quenching and subsequent heat treatment of 35BaO-xTiO<inf>2</inf>-110B<inf>2</inf>O<inf>3</inf> (in mol) (x = 20, 25, and 30) glasses. X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM) results clearly reveal the formation of highly-crystalline anatase nanocrystals in glass matrices. The average crystal size ranges from ∼10 to 20 nm according to TiO<inf>2</inf> contents. Non-isothermal kinetic analyses were performed to understand the crystallization behavior of each glass using differential scanning calorimetry (DSC) scan curves. With the increase of TiO<inf>2</inf> contents in the glass, the crystallization peak temperature of TiO<inf>2</inf> decreases, while the activation energy for crystallization increases. We propose a possible mechanism for the formation of TiO<inf>2</inf> nanocrystals based upon kinetic analysis results and structural changes in barium titanoborate glass matrices according to TiO<inf>2</inf> contents. The nanocrystalline glass-ceramics show ∼60-75% visible light transmittance and sharp UV-light absorption edges at ∼387 nm, corresponding to the energy band gap of anatase (3.2 eV). They show apparent photocatalytic properties and ∼70% of methylene blue solution was decomposed within 180 min.
| Original language | English |
|---|---|
| Article number | 34621 |
| Pages (from-to) | 1022-1027 |
| Number of pages | 6 |
| Journal | Journal of Alloys and Compounds |
| Volume | 647 |
| DOIs | |
| Publication status | Published - 2015 Jul 8 |
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Keywords
- Anatase
- Glass-ceramic
- Nanocrystals
- Non-isothermal kinetics
- Photocatalytic effect
ASJC Scopus subject areas
- Mechanical Engineering
- Mechanics of Materials
- Materials Chemistry
- Metals and Alloys
Cite this
Kinetic and structural analyses for the formation of anatase nanocrystals in barium titanoborate glasses. / Choi, Jong Youn; Sung, Yun Mo.
In: Journal of Alloys and Compounds, Vol. 647, 34621, 08.07.2015, p. 1022-1027.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Kinetic and structural analyses for the formation of anatase nanocrystals in barium titanoborate glasses
AU - Choi, Jong Youn
AU - Sung, Yun Mo
PY - 2015/7/8
Y1 - 2015/7/8
N2 - Abstract Transparent barium titanoborate glass-ceramics bearing TiO2 (anantase) nanocrystals were prepared by the conventional melt-quenching and subsequent heat treatment of 35BaO-xTiO2-110B2O3 (in mol) (x = 20, 25, and 30) glasses. X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM) results clearly reveal the formation of highly-crystalline anatase nanocrystals in glass matrices. The average crystal size ranges from ∼10 to 20 nm according to TiO2 contents. Non-isothermal kinetic analyses were performed to understand the crystallization behavior of each glass using differential scanning calorimetry (DSC) scan curves. With the increase of TiO2 contents in the glass, the crystallization peak temperature of TiO2 decreases, while the activation energy for crystallization increases. We propose a possible mechanism for the formation of TiO2 nanocrystals based upon kinetic analysis results and structural changes in barium titanoborate glass matrices according to TiO2 contents. The nanocrystalline glass-ceramics show ∼60-75% visible light transmittance and sharp UV-light absorption edges at ∼387 nm, corresponding to the energy band gap of anatase (3.2 eV). They show apparent photocatalytic properties and ∼70% of methylene blue solution was decomposed within 180 min.
AB - Abstract Transparent barium titanoborate glass-ceramics bearing TiO2 (anantase) nanocrystals were prepared by the conventional melt-quenching and subsequent heat treatment of 35BaO-xTiO2-110B2O3 (in mol) (x = 20, 25, and 30) glasses. X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM) results clearly reveal the formation of highly-crystalline anatase nanocrystals in glass matrices. The average crystal size ranges from ∼10 to 20 nm according to TiO2 contents. Non-isothermal kinetic analyses were performed to understand the crystallization behavior of each glass using differential scanning calorimetry (DSC) scan curves. With the increase of TiO2 contents in the glass, the crystallization peak temperature of TiO2 decreases, while the activation energy for crystallization increases. We propose a possible mechanism for the formation of TiO2 nanocrystals based upon kinetic analysis results and structural changes in barium titanoborate glass matrices according to TiO2 contents. The nanocrystalline glass-ceramics show ∼60-75% visible light transmittance and sharp UV-light absorption edges at ∼387 nm, corresponding to the energy band gap of anatase (3.2 eV). They show apparent photocatalytic properties and ∼70% of methylene blue solution was decomposed within 180 min.
KW - Anatase
KW - Glass-ceramic
KW - Nanocrystals
KW - Non-isothermal kinetics
KW - Photocatalytic effect
UR - http://www.scopus.com/inward/record.url?scp=84936802578&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84936802578&partnerID=8YFLogxK
U2 - 10.1016/j.jallcom.2015.06.213
DO - 10.1016/j.jallcom.2015.06.213
M3 - Article
AN - SCOPUS:84936802578
VL - 647
SP - 1022
EP - 1027
JO - Journal of Alloys and Compounds
JF - Journal of Alloys and Compounds
SN - 0925-8388
M1 - 34621
ER -