INFRARED SPECTROSCOPY OF UNDOPED AND LA AND Sb DOPED BaTiO3 PREPARED BY POLYMERIC PRECURSORS METHOD
Апстракт
The infrared spectra of ABO3 perovskites have been studied extensively. Factor
group analysis for BaTiO3 with cubic symmetry (space group Pm3m : O6r) predicts only
infrared bands (three triply degenerate infrared active modes of F1o symmetry) and one
optically silent (neither infrared nor Raman active) mode of F2u symmetry. The three
infrared active modes are commonly called the stretching modes (B-O bond-length
modulation), and the external mode in which the 8Oo octahedron vibrates against the I
atoms. In tetragonal symmetry (space group P4mm : C4v), 12 fundamental optical modes
with the following irreducible representation are expected: 3Ab 4E and Br [2,3]. The
perovskite structure has capability to host ions of different size, so a large number of
different dopants can be accommodated in the BaTiO3 lattice that makes BaTiO3
semiconductive. Doping of BT ceramics is very important for obtaining very interesting
characteristics for potential applications.
The aim of this st...udy is to investigate the influence of La- and Sb- doping on the
BaTiO3 synthesized through the Pechini method. Infrared spectroscopy was used in
addition to the XRD, Raman spectroscopy and SEM investigations in order to find
evidence of the structural phase in undoped and doped BaTiO: ceramics'
BaTiO3 powders were prepared by the polymeric organometallic precursors method
(Pechini process) using barium and titanium citrates and for doping were used lanthanum
nitrate and antimony acetate. The powders were isostatically pressed into pellets 8 mm in
diameter and average thickness of about 2.5 mm at pressure of 98.1 MPa. Sintering was
performed at 1300'C for 8 h and the heating rate was 10 oC/min with nature cooling in an
air atmosphere. Far-infrared reflectivity measurements were made in spectral range (50-700
cm-1; at room temperature with BOMEM DA8 spectrometer.
Figure 1 show the IR spectrum of the BaTiO3 and La- and Sb-doped BaTiO3
ceramics sintered at 1300C for 8 h. The bands in the lower wave number range (50-700
cm-1) are due to Ti-O vibrations. The characteristic peak is found for all samples. The
modes at 180 and 470 cm-r belong to the At representation to which the soft phonon mode
associated with the ferroelectric phase transition at Tc - 395 K belongs. The broad band
over 50-180 cm-' is due to soft phonon. Because of the over damped character of the soft
phonon, it is difficult to determine the frequency. The intensity of three peaks of the doped
BT 0.5 mol% Sb, undoped barium titanate and BT doped 0.5 mol % La appear on 183, 184
and 185 cm-1, respectively, intensities of the mode's at 180, 250 and 470 cm-t decrease
for BaTio3 and La- and Sb-doped BaTiO3:, respectively. The modes at 382' 439 and 612
cm-t can be observed in case Sb- doped BaTiO3. This suggests a change of crystal
structure. These results are in agreement with our previous investigations [4]. All
observations related to IR indicate the formation of pure single phase of BT and La and Sb doped BT.
Кључне речи:
infrared spectra / BaTiO3 / Pechini method / IR spectrum / crystal structureИзвор:
Final Workshop COST 539, 28-30 October 2009, Aveiro, Portugal, Programme and book of extended abstracts, p 78-79, 2009Издавач:
- Final Workshop COST 539, 28-30 October 2009, Aveiro, Portugal, Programme and book of extended abstracts, p 78-79
Институција/група
Institut za multidisciplinarna istraživanjaTY - CONF AU - Lazarevic, Zorica AU - Romcevic, Nebojsa AU - Vijatović Petrović, Mirjana AU - Stojanović, Biljana PY - 2009 UR - http://rimsi.imsi.bg.ac.rs/handle/123456789/2724 AB - The infrared spectra of ABO3 perovskites have been studied extensively. Factor group analysis for BaTiO3 with cubic symmetry (space group Pm3m : O6r) predicts only infrared bands (three triply degenerate infrared active modes of F1o symmetry) and one optically silent (neither infrared nor Raman active) mode of F2u symmetry. The three infrared active modes are commonly called the stretching modes (B-O bond-length modulation), and the external mode in which the 8Oo octahedron vibrates against the I atoms. In tetragonal symmetry (space group P4mm : C4v), 12 fundamental optical modes with the following irreducible representation are expected: 3Ab 4E and Br [2,3]. The perovskite structure has capability to host ions of different size, so a large number of different dopants can be accommodated in the BaTiO3 lattice that makes BaTiO3 semiconductive. Doping of BT ceramics is very important for obtaining very interesting characteristics for potential applications. The aim of this study is to investigate the influence of La- and Sb- doping on the BaTiO3 synthesized through the Pechini method. Infrared spectroscopy was used in addition to the XRD, Raman spectroscopy and SEM investigations in order to find evidence of the structural phase in undoped and doped BaTiO: ceramics' BaTiO3 powders were prepared by the polymeric organometallic precursors method (Pechini process) using barium and titanium citrates and for doping were used lanthanum nitrate and antimony acetate. The powders were isostatically pressed into pellets 8 mm in diameter and average thickness of about 2.5 mm at pressure of 98.1 MPa. Sintering was performed at 1300'C for 8 h and the heating rate was 10 oC/min with nature cooling in an air atmosphere. Far-infrared reflectivity measurements were made in spectral range (50-700 cm-1; at room temperature with BOMEM DA8 spectrometer. Figure 1 show the IR spectrum of the BaTiO3 and La- and Sb-doped BaTiO3 ceramics sintered at 1300C for 8 h. The bands in the lower wave number range (50-700 cm-1) are due to Ti-O vibrations. The characteristic peak is found for all samples. The modes at 180 and 470 cm-r belong to the At representation to which the soft phonon mode associated with the ferroelectric phase transition at Tc - 395 K belongs. The broad band over 50-180 cm-' is due to soft phonon. Because of the over damped character of the soft phonon, it is difficult to determine the frequency. The intensity of three peaks of the doped BT 0.5 mol% Sb, undoped barium titanate and BT doped 0.5 mol % La appear on 183, 184 and 185 cm-1, respectively, intensities of the mode's at 180, 250 and 470 cm-t decrease for BaTio3 and La- and Sb-doped BaTiO3:, respectively. The modes at 382' 439 and 612 cm-t can be observed in case Sb- doped BaTiO3. This suggests a change of crystal structure. These results are in agreement with our previous investigations [4]. All observations related to IR indicate the formation of pure single phase of BT and La and Sb doped BT. PB - Final Workshop COST 539, 28-30 October 2009, Aveiro, Portugal, Programme and book of extended abstracts, p 78-79 C3 - Final Workshop COST 539, 28-30 October 2009, Aveiro, Portugal, Programme and book of extended abstracts, p 78-79 T1 - INFRARED SPECTROSCOPY OF UNDOPED AND LA AND Sb DOPED BaTiO3 PREPARED BY POLYMERIC PRECURSORS METHOD UR - https://hdl.handle.net/21.15107/rcub_rimsi_2724 ER -
@conference{ author = "Lazarevic, Zorica and Romcevic, Nebojsa and Vijatović Petrović, Mirjana and Stojanović, Biljana", year = "2009", abstract = "The infrared spectra of ABO3 perovskites have been studied extensively. Factor group analysis for BaTiO3 with cubic symmetry (space group Pm3m : O6r) predicts only infrared bands (three triply degenerate infrared active modes of F1o symmetry) and one optically silent (neither infrared nor Raman active) mode of F2u symmetry. The three infrared active modes are commonly called the stretching modes (B-O bond-length modulation), and the external mode in which the 8Oo octahedron vibrates against the I atoms. In tetragonal symmetry (space group P4mm : C4v), 12 fundamental optical modes with the following irreducible representation are expected: 3Ab 4E and Br [2,3]. The perovskite structure has capability to host ions of different size, so a large number of different dopants can be accommodated in the BaTiO3 lattice that makes BaTiO3 semiconductive. Doping of BT ceramics is very important for obtaining very interesting characteristics for potential applications. The aim of this study is to investigate the influence of La- and Sb- doping on the BaTiO3 synthesized through the Pechini method. Infrared spectroscopy was used in addition to the XRD, Raman spectroscopy and SEM investigations in order to find evidence of the structural phase in undoped and doped BaTiO: ceramics' BaTiO3 powders were prepared by the polymeric organometallic precursors method (Pechini process) using barium and titanium citrates and for doping were used lanthanum nitrate and antimony acetate. The powders were isostatically pressed into pellets 8 mm in diameter and average thickness of about 2.5 mm at pressure of 98.1 MPa. Sintering was performed at 1300'C for 8 h and the heating rate was 10 oC/min with nature cooling in an air atmosphere. Far-infrared reflectivity measurements were made in spectral range (50-700 cm-1; at room temperature with BOMEM DA8 spectrometer. Figure 1 show the IR spectrum of the BaTiO3 and La- and Sb-doped BaTiO3 ceramics sintered at 1300C for 8 h. The bands in the lower wave number range (50-700 cm-1) are due to Ti-O vibrations. The characteristic peak is found for all samples. The modes at 180 and 470 cm-r belong to the At representation to which the soft phonon mode associated with the ferroelectric phase transition at Tc - 395 K belongs. The broad band over 50-180 cm-' is due to soft phonon. Because of the over damped character of the soft phonon, it is difficult to determine the frequency. The intensity of three peaks of the doped BT 0.5 mol% Sb, undoped barium titanate and BT doped 0.5 mol % La appear on 183, 184 and 185 cm-1, respectively, intensities of the mode's at 180, 250 and 470 cm-t decrease for BaTio3 and La- and Sb-doped BaTiO3:, respectively. The modes at 382' 439 and 612 cm-t can be observed in case Sb- doped BaTiO3. This suggests a change of crystal structure. These results are in agreement with our previous investigations [4]. All observations related to IR indicate the formation of pure single phase of BT and La and Sb doped BT.", publisher = "Final Workshop COST 539, 28-30 October 2009, Aveiro, Portugal, Programme and book of extended abstracts, p 78-79", journal = "Final Workshop COST 539, 28-30 October 2009, Aveiro, Portugal, Programme and book of extended abstracts, p 78-79", title = "INFRARED SPECTROSCOPY OF UNDOPED AND LA AND Sb DOPED BaTiO3 PREPARED BY POLYMERIC PRECURSORS METHOD", url = "https://hdl.handle.net/21.15107/rcub_rimsi_2724" }
Lazarevic, Z., Romcevic, N., Vijatović Petrović, M.,& Stojanović, B.. (2009). INFRARED SPECTROSCOPY OF UNDOPED AND LA AND Sb DOPED BaTiO3 PREPARED BY POLYMERIC PRECURSORS METHOD. in Final Workshop COST 539, 28-30 October 2009, Aveiro, Portugal, Programme and book of extended abstracts, p 78-79 Final Workshop COST 539, 28-30 October 2009, Aveiro, Portugal, Programme and book of extended abstracts, p 78-79.. https://hdl.handle.net/21.15107/rcub_rimsi_2724
Lazarevic Z, Romcevic N, Vijatović Petrović M, Stojanović B. INFRARED SPECTROSCOPY OF UNDOPED AND LA AND Sb DOPED BaTiO3 PREPARED BY POLYMERIC PRECURSORS METHOD. in Final Workshop COST 539, 28-30 October 2009, Aveiro, Portugal, Programme and book of extended abstracts, p 78-79. 2009;. https://hdl.handle.net/21.15107/rcub_rimsi_2724 .
Lazarevic, Zorica, Romcevic, Nebojsa, Vijatović Petrović, Mirjana, Stojanović, Biljana, "INFRARED SPECTROSCOPY OF UNDOPED AND LA AND Sb DOPED BaTiO3 PREPARED BY POLYMERIC PRECURSORS METHOD" in Final Workshop COST 539, 28-30 October 2009, Aveiro, Portugal, Programme and book of extended abstracts, p 78-79 (2009), https://hdl.handle.net/21.15107/rcub_rimsi_2724 .