Summary of the refined lattice parameters, crystallite size and strain of the BTFO and BLB523 composite.
Abstract
In this chapter, we introduce a promising composite material, which can be used as a potential candidate in the field of charge storage, sensors, and spintronic devices. The structural, magnetic, and magnetodielectric properties of the pure cum composite samples are investigated. The Rietveld refinement of the X-ray data confirmed the presence of a single (A21am) and mixed phases (A21am + R-3c + Pbam) in the pure and composite sample, correspondingly. The SEM microstructure suggests the contrasting nature of the homogeneous and heterogeneous distribution of grains in the corresponding pure and composite sample. The magnetic properties of the composite sample increase due to the enhanced exchange interaction between the different magnetic ions. The frequency-dependent dielectric subjected to a constant magnetic field indicates the signature of magnetodielectric (MD) coupling for both the samples. The field variation of the MD loop shows the symmetric hysteresis loop in the composite due to the addition of magnetostrictive La0.67Sr0.33MnO3 and the non-collinear antiferromagnetic Bi2Fe4O9 phase. The maximum value of MD% (~0.12%) is enhanced by ~13 times in the composite than in the pure sample. Therefore, the improved MD coupling and symmetric switching of the MD loop of the composite make it a suitable candidate for low power consumption storage devices.
Keywords
- composite
- sol–gel modified method
- magnetodielectric
- Magnetoloss
1. Introduction
Ceramic materials are in demand due to their growing use in energy harvesting technologies, including batteries, capacitors, and storage devices [1]. There are two types of ceramic materials, i.e., traditional and advanced. The advanced ceramic material plays a significant role in the sensor and storage devices due to its high piezoelectric and resistive properties. These materials include oxides, nitrates, and carbides [2]. In these ceramics, the unique ferroelectric, electrochemical, pyroelectric, and piezoelectric properties are often useful for multiferroic research. The multiferroic materials with the simultaneous occurrence of various ferroic orders such as ferro (electric/magnetic), antiferromagnetic (AFM), ferrotoridic, and ferroelastic play a significant role in developing new technological and device applications [3]. In the recent past, researchers are focused on device miniaturization, which satisfies the vast need to integrate the electric and magnetic properties in a material. There are a variety of coupling mechanisms between the electric and magnetic orders, but magnetoelectric (ME) coupling is crucial for future micro/nanoscale electronics, low-power memory devices, and spintronic devices [4]. The ME effect was initially studied in the Cr2O3 single-phase compound. After that, many materials such as DyMn2O5, TbMnO3, and BiFeO3 showed the ME coupling in its single-phase [5]. However, these materials restrict their practical suitability applications due to the weak coupling among the electric and magnetic order parameters and the transition temperature below the room temperature (RT). To avoid the above difficulties in the single-phase materials, many researchers have focused their study on designing the composite materials [6]. Usually, in composite, the electric and magnetic properties are intentionally improved by adding the required electric and magnetic phases. The induced ME coupling in the composite is the product property relation between the constituent phases. The relation between the magnetic and electric phases is written as [7]:
The origin of ME coupling in the composite may be strain, charge, and exchange bias mediated. It depends upon the coupling interaction at the magnetic and electric phase interface.
The alternative approach to study the coupling among the magnetic and electric ordering is the magnetodielectric (MD) effect. The existence of ME coupling can indirectly address through the MD effect. This phenomenon is defined as the magnetic field-controlled dielectric properties and reversely electric field-induced magnetic permeability [8]. Materials having MD characteristics are rich in physical content to take further research and its practical utilization. Usually, the signature of the MD effect can be realized by observing the anomaly of magnetic/dielectric transition in the dielectric/magnetic properties. The MD effect can be experienced experimentally by measuring the capacitance at the different external magnetic fields. The microscopic source of the MD effect can be originated from the extrinsic and intrinsic mechanisms. It solely depends on the origin of the dielectric properties of the material. According to G. Catalan, the MD effect can arise without having the dielectric and magnetic coupling in the sample [9]. The extrinsic mechanism responsible for the origin of the MD effect is the magnetoresistance and Maxwell-Wagner effect of the sample. Similarly, the intrinsic source of the MD effect originated from the magnetic field-induced dipolar switching mechanism. Hence, the existence of an intrinsic MD effect in a material indicates the possible signal of ME coupling. The realization of ME coupling is restricted by the symmetry requirements. The MD materials are fascinating due to their multiple microscopic origins and simplicity for device application. Recently, the MD coupling has been used to characterize the magnetic multipole orders and quantum criticality [10]. Therefore, it is necessary to investigate the MD coupling and the improvement of dielectric properties with the applied magnetic field.
The Aurivillius compound is composed of the perovskite layer (A
In this work, we have examined the physical properties of the 0.5Bi5Ti3FeO15-0.2La0.67Sr0.33MnO3-0.3Bi2Fe4O9 composite and compared it with the pure BTFO sample. The composite sample is synthesized by the sol–gel-modified technique and their dielectric, magnetic, and the source of MD effect are discussed. MD coupling in composite might be used as a potential candidate for MD device design.
2. Experimental
2.1 Synthesis of the composite samples
The ceramic composites (0.5Bi5Ti3FeO15-0.2La0.67Sr0.33MnO3-0.3Bi2Fe4O9) were prepared by the sol–gel modified method. At first, BTFO, LSMO, and BFO samples were synthesized separately via a sol–gel auto combustion process. The chemical reagent used for the preparation of the BTFO sample were bismuth nitrate (Bi(NO3)3.5H2O), iron nitrate (Fe(NO3)3.9H2O), and titanium isopropoxide (TiC12H28O4). The above chemicals were taken from Sigma-Aldrich with greater than 99.9% purity form. The deionized water was used to mix the nitrates. Bismuth nitrate and titanium isopropoxide were immiscible with the deionized water. The required drop of nitric acid was used to dissolve the chemicals and get the transparent white-colored solution. After that, add the iron nitrate to the above solution and heat it on the hot plate at 100°C. Then the desired ratio of ethylene glycol and citric acid (1:1.5) was added to the mixture. All the reagents are mixed completely and lead to the formation of the gel. The xerogel was dried on the hot plate overnight and crushed to form the homogenous powder. The resultant powder was pre-sintered in a tubular furnace at 600°C for 2 h. A similar method was used for the preparation of LSMO and BFO samples. Only the difference in the precursor materials and pre-sintered temperatures. The starting materials such as lanthanum nitrate (La(NO3)3.6H2O), manganese nitrate (Mn(NO3)2.4H2O), strontium nitrate (Sr(NO3)2) and bismuth nitrate, iron nitrate were used for the preparation of LSMO and BFO sample, respectively. The obtained xerogel powder was pre-sintered at 800°C for 4 h and 800°C for 2 h for the LSMO and BFO samples, respectively.
Finally, the composite (0.5Bi5Ti3FeO15-0.2La0.67Sr0.33MnO3-0.3Bi2Fe4O9) was prepared by taking the desired ratio of as-synthesized BTFO, LSMO, and BFO powder. The proper weight percentage of 50% BTFO:20% LSMO:30% BFO (abbreviated as BLB523) was taken and mixed thoroughly with the help of agate mortar and pestle to get the homogeneous powder. The obtained powder was pressed to form the pellet and finally sintered at 900°C for 4 h.
2.2 Characterization
The phase identification of the pure cum composite samples was analyzed by using the X-ray diffraction (XRD) system with an ULTIMA-IV diffractometer of Cu source of radiation. The diffraction data were taken in the range of 20–60° with a slow scan rate of 3 degrees per minute. The surface morphology and elemental analysis were characterized through the scanning electron microscope (SEM) coupled with the energy dispersive X-ray spectrometer (EDAX). The size of the grains was estimated from the Image J Software. The samples magnetic properties were studied at room temperature (RT) using the vibrating sample magnetometer (VSM) with a maximum magnetic field of 15 kOe. For the electrical measurement samples were painted with high-quality silver paste to form an electrode. The RT frequency variation of dielectric permittivity at a constant magnetic field (0 to 1.3 T with a difference of 0.2 T) was studied through the impedance analyzer (Waynee Kerr 6500B model). The magnetic field variation of MD and magnetoloss was recorded by an impedance analyzer, which is assembled with the closed cycle refrigerator (CCR) system, KEPECO power supply, and the electromagnet (GMW 5034).
3. Results and discussion
3.1 Structural characterization by XRD
Figure 1(a) and (b) illustrate the XRD patterns of the pure BTFO and composite (BLB523) samples. The measured XRD data is examined through the Rietveld refinement procedure using the Fullprof software. The refinement result provides information related to the samples pure phase formation and structural parameters. For the pure BTFO sample, the single-phase refinement method is performed by considering the orthorhombic crystal structure (
BTFO (pure) | BLB523 (composite) | |||
---|---|---|---|---|
Parameters | BTFO phase | LSMO phase | BFO phase | |
Crystal system | Orthorhombic | Orthorhombic | Rhombohedral | Orthorhombic |
Space group | ||||
Lattice parameters (Å) | ||||
Cell volume (Å3) | 1224.63(10) | 1218.995(6) | 364.33(7) | 386.36(9) |
Phase fraction | 100 | 50.79 | 20.63 | 28.58 |
2.20 | 10.4 | |||
2.25 | 9.65 | |||
1.84 | 3.07 | |||
Crystallite size (nm) | 41.76 | 51.35 | ||
Strain | 10.2 × 10−4 | 18.2 × 10−4 |
The mean lattice strain and crystallite size of the pure cum composite samples have been extracted from the Williamson-Hall (W-H) plot method. The mathematical expression of the W-H method is
here
3.2 SEM study
The surface micrograph of sintered pure cum composite samples are shown in Figure 2(a) and (b). These images reveal the existence of grains with different sizes and orientations in the samples. The pure sample consists of well-structured plate-like grains of various sizes distributed uniformly on the sample surface. At the same time, the composite consists of a mixture of three phases (BTFO, LSMO, and BFO). As LSMO grains exist in the nanometer range, it is difficult to identify from the SEM image. The average grain size of the pure and composite sample (mixed grains) is found to be 1.44 and 0.54 μm, respectively, which is estimated from the Image J software. The EDAX analysis is incorporated to analyze the sample’s elemental composition, as shown in Figure 2(c) and (d). The EDAX spectrum indicates the constituent elemental peaks of the Bi, Ti, Fe, O and Bi, Ti, Fe, La, Sr., Mn, and O for pure and composite samples. This analysis confirms the presence of the required element in the samples.
3.3 Magnetic study
The magnetization (M) versus magnetic field (H) loop for pure BTFO and composite BLB523 samples are recorded at RT. Figure 3(a) and (b) display the linear and slightly non-linear M-H loop of pure cum composite samples. This linear behavior of the M-H loop indicates the paramagnetic (PM) behavior of the pure sample. With the addition of magnetic LSMO and BFO phase, the M-H loop slightly changes to the non-linear behavior with a small opening in the field range of ±1 kOe, as shown lower inset of Figure 3(b). This behavior signifies the weak ferromagnetic (FM) nature of composite. In composite BLB523, saturation magnetization is not achieved even in a high magnetic field of 15 kOe. It indicates the presence of canted spins in the composite. Since the composite sample consists of the three magnetic phases, i.e
Sample | ||||
---|---|---|---|---|
BTFO | 0.07 ± 0.02 | 3.44 × 10−4 ±6.12 × 10−6 | 50 ± 8 | 0.005 |
BLB523 | 0.23 ± 0.06 | 35.74 × 10−4 ±8.37 × 10−6 | 145 ± 21 | 0.016 |
In the present discussion, the coercivity value of the BLB523 composite is increased to 145 Oe (nearly three times) than the pure sample. It could be due to the addition of manganite (LSMO) and ferrite (BFO) phase leading to the hindrance of domain interaction and resulting in the pinning effect in the composite. A similar trend of coercivity is also observed in many composites [21]. The enhanced magnetization in the composite sample is addressed due to adding extra magnetic ions, i.e
3.4 Dielectric study
The frequency variation of dielectric permittivity (
3.5 Magnetic field-dependent MD analysis
To realize the influence of magnetic field on dielectric properties of the pure and composite samples, field variation of MD measurement is recorded at RT. The MD effect can be extracted experimentally by recording the field variation dielectric data. While for the magnetoloss (ML) effect, dielectric loss data is taken as a function of a magnetic field. Both the MD and ML percentage is estimated using the following mathematical expression [19]:
here
4. Conclusion
In summary, the pure cum composite (0.5Bi5Ti3FeO15-0.2La0.67Sr0.33MnO3-0.3Bi2Fe4O9) is successfully prepared by using the sol–gel and its modified technique. The XRD analysis confirmed the existence of single (
Acknowledgments
All authors would like to acknowledge the Board of Research in Nuclear Science (Project No: 2012/37P/40/BRNS/2145), Mumbai, the UGC-DAE CSR Mumbai (Project No: CRS/2021-2022/03/585), and the Department of Science and Technology (Project No: SR/FTP/PS-187/2011), New Delhi for funding.
References
- 1.
Cramer CL, Ionescu E, Zajac MG, Nelson AT, Katoh Y, Haslam JJ, et al. Additive manufacturing of ceramic materials for energy applications: Road map and opportunities. Journal of the European Ceramic Society. 2022; 42 :3049-3088. DOI: 10.1016/j.jeurceramsoc.2022.01.058 - 2.
Chalia S, Bharti MK, Thakur P, Thakur A, Sridhara SN. An overview of ceramic materials and their composites in porous media burner applications. Ceramics International. 2021; 47 :10426-10441. DOI: 10.1016/j.ceramint.2020.12.202 - 3.
Scott JF. Room-temperature multiferroic magnetoelectrics. NPG Asia Materials. 2013; 5 :1-11. DOI: 10.1038/am.2013.58 - 4.
Spaldin NA, Ramesh R. Advances in magnetoelectric multiferroics. Nature Materials. 2019; 18 :203-212. DOI: 10.1038/s41563-018-0275-2 - 5.
Ortega N, Ashok K, Scott JF, Katiyar RS. Multifunctional magnetoelectric materials for device applications. Journal of Physics: Condensed Matter. 2015; 27 :1-23. DOI: 10.1088/0953-8984/27/50/504002 - 6.
Chen J, Bai Y, Nie C, Zhao S. Strong magnetoelectric effect of Bi4Ti3O12/Bi5Ti3FeO15 composite films. Journal of Alloys and Compounds. 2016; 663 :480-486. DOI: 10.1016/j.jallcom.2015.12.088 - 7.
Nan CW, Bichurin MI, Dong S, Viehland D, Srinivasan G. Multiferroics magnetoelectric composites: Historical perspective, status, and future directions. Journal of Applied Physics. 2008; 103 :1-35. DOI: 10.1063/1.2836410 - 8.
Yao X, Zhou JP, Zhang XL, Chen XM. Magnetodielctric mechanism and application of magnetoelectric composites. Journal of Magnetism and Magnetic Materials. 2022; 550 :1-11. DOI: 10.1016/j.jmmm.2022.169099 - 9.
Catalan G. Magnetocapacitance without magnetoelectric coupling. Applied Physics Letter. 2006; 88 :1-3. DOI: 10.1063/1.2177543 - 10.
Huang S, Jin H, Wan KQ , Wang HO, Su KP, Yang DX, et al. The antiferromagnetic ordering and metamagnetic transition induced magnetoelectric effect in Dy2Cu2O5. Journal of Applied Physics. 2022; 131 :1-6. DOI: 10.1063/5.0071660 - 11.
Birenbaum AY, Scaramucci A, Ederer C. Magnetic order in four-layered Aurivillius phases. Physical Review B. 2017; 95 :1-10. DOI: 10.1103/PhysRevB.95.104419 - 12.
Jena R, Chandrakanta K, Pal P, Abdullah MF, Kaushik SD, Singh AK. Dielectric relaxation and conduction mechanism in Aurivillius ceramic Bi5Ti3FeO15. International Journal of Minerals, metallurgy, and Materials. 2021; 28 :1063-1071. DOI: 10.1007/s12613-020-2091-3 - 13.
Majumdar S, Dijken SV. Pulsed laser deposition of La1-xSrxMnO3: Thin film properties and spintronic applications. Journal of Physics D: Applied Physics. 2014; 47 :1-15. DOI: 10.1088/0022-3727/47/3/034010 - 14.
Pooladi M, Sharifi I, Behzadipour M. A review of the structure, magnetic, and electric properties of the bismuth ferrite (Bi2Fe4O9). Ceramics International. 2020; 46 :18453-18463. DOI: 10.1016/j.ceramint.2020.04.241 - 15.
Pandey R, Pradhan LK, Kumar S, Supriya S, Singh RK, Kar M. Correlation between lattice strain and physical (magnetic, dielectric, and magnetodielectric) properties of perovskite-spinel (Bi0.85La0.15FeO3)(1-x)- (NiFe2O4)(x) composites. Journal of Applied Physics. 2019; 125 :1-11. DOI: 10.1063/1.5063775 - 16.
Verma KC, Singh M, Kotnala RK, Goyal N. Magnetic field control of polarization/capacitance/voltage/resistance through lattice strain in BaTiO3-CoFe2O4 multiferroic nanocomposite. Journal of Magnetism and Magnetic Materials. 2019; 469 :483-493. DOI: 10.1016/j.jmmm.2018.09.020 - 17.
Ahmed MA, Bishay ST, Salem-Gaballah SM. Structural characterization and magnetic properties of smart CuCd ferrite/LaSrCo manganite nanocomposites. Journal of Magnetism and Magnetic Materials. 2013; 334 :96-101. DOI: 10.1016/j.jmmm.2013.01.022 - 18.
Wang Y, Xu G, Yang L, Ren Z, Wei X, Weng W, et al. Low-temperature synthesis of Bi2Fe4O9 nanoparticles via a hydrothermal method. Ceramic International. 2009; 35 :51-53. DOI: 10.1016/j.ceramint.2007.09.114 - 19.
Jena R, Chandrakanta K, Abdullah MF, Pal P, Kaushik SD, Singh AK. Structural, magnetic, and magnetodielectric correlations in multiferroic Bi5Ti3FeO15. Journal of Material Science: Materials in Electronics. 2021; 32 :21379-21394. DOI: 10.1007/s10854-021-06641-8 - 20.
Sharma S, Sharma H, Thakur S, Shah J, Kotnala RK, Negi NS. Structural, magnetic, magneto-dielectric and magneto-electric properties of (1-x)Ba0.85Ca0.15Ti0.90Zr0.10O3-(x) CoFe2O4 ;lead-free multiferroic composites sintered at higher temperature. Journal of Magnetism and Magnetic Materials. 2021; 538 :1-9. DOI: 10.1016/j.jmmm.2021.168243 - 21.
Bharadwaj S, Tirupathi A, Kumar NP, Pola S, Lakshmi YK. Study of magnetic and magnetoresistance behaviour of La0.67Sr0.33MnO3-CoFe2O4 composites. Journal of Magnetism and Magnetic Materials. 2020; 513 :1-9. DOI: 10.1016/j.jmmm.2020.167058 - 22.
Mohapatra SR, Vishwakarma PN, Kaushik SD, Singh AK. Effect of holmium substitution on the magnetic and magnetodielectric properties of multiferroic Bi2Fe4O9. Journal of Applied Physics. 2017; 122 :1-9. DOI: 10.1063/1.4994645 - 23.
Chandrakanta K, Jena R, Pal P, Abdullah MF, Sahu DP, Kaushik SD, et al. Temperature-dependent magnetodielectric, magnetoimpedance, and magnetic field controlled dielectric relaxation response in KBiFe2O5. Journal of Magnetism and Magnetic Materials. 2022; 549 :1-8. DOI: 10.1016/j.jmmm.2022.169047 - 24.
Wu H, Xu R, Zhou C, Xing S, Zeng Z, Ao H, et al. Effect of core size on the magnetoelectric properties of Cu0.8Co0.2Fe2O4@Ba0.8Sr0.2TiO3 ceramics. Journal of Physics and Chemistry of Solids. 2022; 160 :1-10. DOI: 10.1016/j.jpcs.2021.110314 - 25.
Pal M, Srinivas A, Asthana S. Enhanced magneto-electric properties and magnetodielectric effect in lead-free (1-x)0.94Na0.5Bi0.5TiO3-0.06BaTiO3-xCoFe2O4 particulate composites. Journal of Alloys and Compounds. 2022; 900 :1-13. DOI: 10.1016/j.jallcom.2021.163487 - 26.
Rather MD, Samad R, Hassan N, Want B. Magnetodielectric effect in rare-earth doped BaTiO3-CoFe2O4 multiferroic composites. Journal of Alloys and Compounds. 2019; 794 :402-416. DOI: 10.1016/j.jallcom.2019.04.244 - 27.
Kimura T. Spiral magnets as magnetoelectrics. The Annual Review of Materials Research. 2007; 37 :387-413. DOI: 10.1146/annurev.matsci.37.052506.084259