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NATIONAL CONFERENCE ON PHYSICS AND CHEMISTRY OF MATERIALS: NCPCM2020, 2021
The structural properties strontium oxide (SrO) in two phases, namely, Rocksalt (B1) and Cesium C... more The structural properties strontium oxide (SrO) in two phases, namely, Rocksalt (B1) and Cesium Chloride (B2) phases, and a structural transition from B1 to B2 structures are presented. We have estimated the effect of pressure on structural and elastic properties of SrO semiconducting material using an effective inter-ionic potential method, which contain the long-range Coulomb and van der Waals (vdW) interactions and the short-range repulsive interaction of up to secondneighbor ions within the Hafemeister and Flygare approach. To calculate the vdW coefficients Slater-Kirkwood variational method was used. Our calculated phase transition pressure (Pt) is 38.5 GPa. We have also focused on the elastic properties of SrO compound within the effective inter-ionic potential approach and the second order elastic constants (SOEC) were predicted in both the phases. The present calculations have provided a good agreement with the available data reported on this compound.
Materials Today: Proceedings, 2021
Abstract This work presents the influence of La3+ and Sr2+ substitution at Bi-site of BiFeO3 in t... more Abstract This work presents the influence of La3+ and Sr2+ substitution at Bi-site of BiFeO3 in the sense of phase, crystal structure and dielectric properties. The Bi1-x (Lax-y Sry)FeO3 (x = 0.1, y = 0, 0.05) ceramics with perovskite structure were synthesized by standard solid state route. Phase analysis exploiting X–ray diffraction (XRD) data disclosed formation of single phased trigonal structure with R3c space group. The calculated lattice parameters for Bi0.9La0.1FeO3 ceramic were a = b = 5.5771 A and c = 13.8021 A and Bi0.9La0.05Sr0.05FeO3 ceramic were a = b = 5.5844 A and c = 13.8215 A which witness trigonal structure. The calculated average crystallite size for Bi0.9La0.1FeO3 and Bi0.9La0.05Sr0.05FeO3 ceramics were 47.39 nm and 31.20 nm respectively. The dielectric analysis reveals that both the ceramics to exhibit good dielectric behavior with high dielectric constant and lower tangential loss value. In addition, Cole-Cole plot (M′ vs. M′′) and Nyquist plot (Z′ vs Z′′) exposed the non-Debye behavior of the ceramics and distribution of different relaxation phenomena in the ceramics.
ADVANCED MATERIALS AND RADIATION PHYSICS (AMRP-2020): 5th National e-Conference on Advanced Materials and Radiation Physics, 2021
In this presented work, we report the synthesis and characterization of A-site doped multiferroic... more In this presented work, we report the synthesis and characterization of A-site doped multiferroic BiFeO3 by La3+ and Ba2+ The perovskite Bi1-x (Lax-y Bay)FeO3 (x = 0.1, y = 0, 0.05) samples were synthesized using high temperature solid state reaction route and were characterized for structural studies using X-ray diffraction and Raman spectral studies. The Bi(La/Ba)FeO3 samples were further studied for frequency dependent dielectric properties at room temperature. The XRD spectrum analysis infers the samples to be crystalline in nature as well as single phased. The XRD spectral study of as synthesized samples further reveals their crystallization into the trigonal structure with an assigned space group R3c. The intense reflection peaks witness the crystallinity and narrow fullwidth at half maximum indicate the higher average particle size. The average particle size calculated using Scherrer’s formula was 47.39nm for La and 34.32 nm for La/Ba doped BiFeO3. The lattice parameters calculated for La doped BiFeO3 were a = b = 5.5771A and c = 13.8021A and La/Ba doped BiFeO3 were a = b = 5.5844 A and c = 13.8215 A which witness acquired trigonal structure. The dielectric studies reveal the Bi1-x (Lax-y Bay)FeO3 (x = 0.1, y = 0, 0.05) samples to be good dielectric in nature with lower dielectric loss values. The ac conductivity study reveals the samples to be resistive to the applied field to a higher value thereby does not respond but after the certain limit of the applied field, the conductivity abruptly increases which is attributed to the release of the charge carriers by the trap centers after a threshold voltage. The intriguing dielectric and loss character infer these samples is feasible for electo-magnetic device application.
NATIONAL CONFERENCE ON PHYSICS AND CHEMISTRY OF MATERIALS: NCPCM2020, 2021
The structural properties strontium oxide (SrO) in two phases, namely, Rocksalt (B1) and Cesium C... more The structural properties strontium oxide (SrO) in two phases, namely, Rocksalt (B1) and Cesium Chloride (B2) phases, and a structural transition from B1 to B2 structures are presented. We have estimated the effect of pressure on structural and elastic properties of SrO semiconducting material using an effective inter-ionic potential method, which contain the long-range Coulomb and van der Waals (vdW) interactions and the short-range repulsive interaction of up to secondneighbor ions within the Hafemeister and Flygare approach. To calculate the vdW coefficients Slater-Kirkwood variational method was used. Our calculated phase transition pressure (Pt) is 38.5 GPa. We have also focused on the elastic properties of SrO compound within the effective inter-ionic potential approach and the second order elastic constants (SOEC) were predicted in both the phases. The present calculations have provided a good agreement with the available data reported on this compound.
Materials Today: Proceedings, 2021
Abstract This work presents the influence of La3+ and Sr2+ substitution at Bi-site of BiFeO3 in t... more Abstract This work presents the influence of La3+ and Sr2+ substitution at Bi-site of BiFeO3 in the sense of phase, crystal structure and dielectric properties. The Bi1-x (Lax-y Sry)FeO3 (x = 0.1, y = 0, 0.05) ceramics with perovskite structure were synthesized by standard solid state route. Phase analysis exploiting X–ray diffraction (XRD) data disclosed formation of single phased trigonal structure with R3c space group. The calculated lattice parameters for Bi0.9La0.1FeO3 ceramic were a = b = 5.5771 A and c = 13.8021 A and Bi0.9La0.05Sr0.05FeO3 ceramic were a = b = 5.5844 A and c = 13.8215 A which witness trigonal structure. The calculated average crystallite size for Bi0.9La0.1FeO3 and Bi0.9La0.05Sr0.05FeO3 ceramics were 47.39 nm and 31.20 nm respectively. The dielectric analysis reveals that both the ceramics to exhibit good dielectric behavior with high dielectric constant and lower tangential loss value. In addition, Cole-Cole plot (M′ vs. M′′) and Nyquist plot (Z′ vs Z′′) exposed the non-Debye behavior of the ceramics and distribution of different relaxation phenomena in the ceramics.
ADVANCED MATERIALS AND RADIATION PHYSICS (AMRP-2020): 5th National e-Conference on Advanced Materials and Radiation Physics, 2021
In this presented work, we report the synthesis and characterization of A-site doped multiferroic... more In this presented work, we report the synthesis and characterization of A-site doped multiferroic BiFeO3 by La3+ and Ba2+ The perovskite Bi1-x (Lax-y Bay)FeO3 (x = 0.1, y = 0, 0.05) samples were synthesized using high temperature solid state reaction route and were characterized for structural studies using X-ray diffraction and Raman spectral studies. The Bi(La/Ba)FeO3 samples were further studied for frequency dependent dielectric properties at room temperature. The XRD spectrum analysis infers the samples to be crystalline in nature as well as single phased. The XRD spectral study of as synthesized samples further reveals their crystallization into the trigonal structure with an assigned space group R3c. The intense reflection peaks witness the crystallinity and narrow fullwidth at half maximum indicate the higher average particle size. The average particle size calculated using Scherrer’s formula was 47.39nm for La and 34.32 nm for La/Ba doped BiFeO3. The lattice parameters calculated for La doped BiFeO3 were a = b = 5.5771A and c = 13.8021A and La/Ba doped BiFeO3 were a = b = 5.5844 A and c = 13.8215 A which witness acquired trigonal structure. The dielectric studies reveal the Bi1-x (Lax-y Bay)FeO3 (x = 0.1, y = 0, 0.05) samples to be good dielectric in nature with lower dielectric loss values. The ac conductivity study reveals the samples to be resistive to the applied field to a higher value thereby does not respond but after the certain limit of the applied field, the conductivity abruptly increases which is attributed to the release of the charge carriers by the trap centers after a threshold voltage. The intriguing dielectric and loss character infer these samples is feasible for electo-magnetic device application.