TY - JOUR
T1 - A modified plasma arc gas condensation technique to synthesize nanocrystalline tungsten oxide powders
AU - Su, Cherng Yuh
AU - Lin, Chung Kwei
AU - Cheng, Chia Wei
PY - 2005/5
Y1 - 2005/5
N2 - In the present study, nanocrystalline tungsten oxide powders were prepared by a modified plasma arc gas condensation technique where a gas nozzle was introduced to provide blowing gas. With the aid of the blowing gases, nanocrystalline tungsten oxide powders can be prepared under various chamber pressures ranged from 4.9 to 101.3kPa. The mean grain size and powder production rate of the as-prepared nanocrystalline WO3 powders increased with increasing chamber pressure. For an increasing chamber pressure from 4.9 to 101.3 kPa, asignificant increase in powder production rate from 0.374 to 13.658 g/h can be noticed, while the mean grain size only enlarged acceptably from 5.9 to 15.7 nm. Meanwhile, by controlling the partial oxygen pressure of the mixed gas, nanocrystalline blue tungsten oxide powders can be prepared successfully. The blowing mixed gas from the nozzle not only suppressed the nucleation and growth for powders from the gas phase, but can be used to prepare stoichiometric or nonstoichiometric tungsten oxide powders.
AB - In the present study, nanocrystalline tungsten oxide powders were prepared by a modified plasma arc gas condensation technique where a gas nozzle was introduced to provide blowing gas. With the aid of the blowing gases, nanocrystalline tungsten oxide powders can be prepared under various chamber pressures ranged from 4.9 to 101.3kPa. The mean grain size and powder production rate of the as-prepared nanocrystalline WO3 powders increased with increasing chamber pressure. For an increasing chamber pressure from 4.9 to 101.3 kPa, asignificant increase in powder production rate from 0.374 to 13.658 g/h can be noticed, while the mean grain size only enlarged acceptably from 5.9 to 15.7 nm. Meanwhile, by controlling the partial oxygen pressure of the mixed gas, nanocrystalline blue tungsten oxide powders can be prepared successfully. The blowing mixed gas from the nozzle not only suppressed the nucleation and growth for powders from the gas phase, but can be used to prepare stoichiometric or nonstoichiometric tungsten oxide powders.
KW - Nanocrystalline WO powders
KW - Nonstoichiometric tungsten oxide
KW - Plasma arc gas condensation technique
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U2 - 10.2320/matertrans.46.1016
DO - 10.2320/matertrans.46.1016
M3 - Article
AN - SCOPUS:22444431527
VL - 46
SP - 1016
EP - 1020
JO - Materials Transactions
JF - Materials Transactions
SN - 0916-1821
IS - 5
ER -