Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
Phase Formation of Co and Cr Co-Doped Bismuth Niobate with Pyrochlore Structure. / Zhuk, Nadezhda; Badanina, Ksenia; Korolev, Roman; Makeev, Boris; Krzhizhanovskaya, Maria; Kharton, Vladislav.
в: Inorganics, Том 11, № 7, 288, 03.07.2023.Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
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TY - JOUR
T1 - Phase Formation of Co and Cr Co-Doped Bismuth Niobate with Pyrochlore Structure
AU - Zhuk, Nadezhda
AU - Badanina, Ksenia
AU - Korolev, Roman
AU - Makeev, Boris
AU - Krzhizhanovskaya, Maria
AU - Kharton, Vladislav
PY - 2023/7/3
Y1 - 2023/7/3
N2 - The formation mechanisms of pyrochlore-type Bi2Co1/2Cr1/2Nb2O9+Δ (space group Fd-3m, a = 10.4838(8) Å), in the temperature range from 400 to 1050 °C were studied by employing X-ray diffraction, scanning electron microscopy and energy-dispersive spectroscopy. An extensive reaction between the binary metal oxides was found to begin at temperatures above 550 °C, following the transition of monoclinic α-Bi2O3 into a tetragonal β-Bi2O3 polymorph. The synthesis process occurs in several stages when Bi-rich intermediate products (Bi6CrO12, Bi6Cr2O15, and Bi5Nb3O15) transform into bismuth-depleted BiNbO4 and a chromium–cobalt spinel is formed. The formation of a single pyrochlore phase occurs at the final reaction stage at 1050 °C via the doping of bismuth ortho-niobate, BiNbO4, by the transition metal cations. The observed mechanism is essentially similar to the mechanism of tantalate-based phases except for the formation of Bi5Nb3O15 at the intermediate reaction stages.
AB - The formation mechanisms of pyrochlore-type Bi2Co1/2Cr1/2Nb2O9+Δ (space group Fd-3m, a = 10.4838(8) Å), in the temperature range from 400 to 1050 °C were studied by employing X-ray diffraction, scanning electron microscopy and energy-dispersive spectroscopy. An extensive reaction between the binary metal oxides was found to begin at temperatures above 550 °C, following the transition of monoclinic α-Bi2O3 into a tetragonal β-Bi2O3 polymorph. The synthesis process occurs in several stages when Bi-rich intermediate products (Bi6CrO12, Bi6Cr2O15, and Bi5Nb3O15) transform into bismuth-depleted BiNbO4 and a chromium–cobalt spinel is formed. The formation of a single pyrochlore phase occurs at the final reaction stage at 1050 °C via the doping of bismuth ortho-niobate, BiNbO4, by the transition metal cations. The observed mechanism is essentially similar to the mechanism of tantalate-based phases except for the formation of Bi5Nb3O15 at the intermediate reaction stages.
UR - https://www.mendeley.com/catalogue/f4edf5c5-3422-3b92-a0fc-8a64c87fd0ba/
U2 - 10.3390/inorganics11070288
DO - 10.3390/inorganics11070288
M3 - Article
VL - 11
JO - Inorganics
JF - Inorganics
SN - 2304-6740
IS - 7
M1 - 288
ER -
ID: 111863032