Phase evolution of strontium bismuth niobate ceramics by conventional solid-state reaction method

Archives of Metallurgy and Materials

“…4) can be due to the presence of some organic groups from incomplete decomposition of solvents/reagents used during the samples preparation. 636.5 and 582.5 cm −1 for both BiNbO 4 -CuO ceramics can be associated with Nb-O stretching of the terminal oxygen atoms in NbO 6 group vibration of NbO 6 octahedra [11]. The positions of these bands maintain for both BiNbO 4 -CuO ceramics suggesting no structural and chemical changes induced by sintering conditions.…”

“…At low energy region it is possible to identify some known absorption bands for the BiNbO 4 . The bands observed at 709-714 cm −1 , 640-645 cm −1 and 597-602 cm −1 for BiNbO 4 -V 2 O 5 ceramics can be associated with Nb-O stretching of the terminal oxygen atoms in NbO 6 group vibration of NbO 6 octahedra [11]. The FTIR band positions associated with NbO 6 octahedra, observed for BiNbO 4 -V 2 O 5 ceramics, suggest that the crystal structure changes after dopant incorporation.…”

“…The bands from 400 to 500 cm −1 are associated with the Bi-O stretching vibrations [11,12]. Whil e the band near 850 cm −1 seems to be associated to the β-BiNbO 4 phase, the 446 cm −1 vibration is related to α-BiNbO 4 phase [6].…”

“…The FTIR spectra of all BiNbO 4 -V 2 O 5 ceramics sintered at T = 910℃ characterises the very weak bands at 3475 cm −1 and 1647 cm −1 which are due to vibrational stretching and deformation bands of O-H groups [13] and the bands in the region 2950-2850 cm −1 , which are attributed to the C-H stretching vibrations [8]. The weak band at 1450 cm −1 can be due to the presence of C = O groups [11] from incomplete decomposition of solvents/reagents used during the preparation of the samples. At low energy region it is possible to identify some known absorption bands for the BiNbO 4 .…”

“…The NbO 6 vibrations associated to Nb-O-Nb bonds are expected at 560 cm -1 and 600 cm -1 to 700 cm -1 , respectively [6,9,10]. Whereas the Nb-O symmetric stretching of the edge sharing oxygen atoms in the edge sharing NbO 6 group is observed at 840 cm -1 [11]. Th e bands usually observed from 810 to 850 cm -1 are related to symmetrical stretching vibrations of Bi-O-Bi [8].…”