abstract
Lead-free multiferroic 3-0 type particulate composites with a composition (1-x)(Ba0.85Ca0.15Zr0.1Ti0.9O3) - x(Ni0.7Zn0.3Fe2O4) [(1-x)BCZT - xNZFO with 0 <= x <= 100 at%] were prepared using solid state reaction method. Structural and microstructural analysis using XRD, FESEM and Raman techniques confirmed the phase formation of the ferroelectric (BCZT) and magnetostrictive (NZFO) phases without any detectable presence of impurity phases. Rietveld refinement of the XRD data revealed a tetragonal (P4mm) and a cubic structure (Fd (3) over barm) for the BCZT and NZFO phases, respectively. Elemental compositions of the constituent phases were assessed by EDS and XPS analyses. Electrical, magnetic, and magnetoelectric (ME) measurements were performed. The composites exhibit typical well-saturated magnetic hysteresis (M-H) loops at room temperature, having very low coercive field (H-C) values, indicating their soft ferromagnetic behavior. Various parameters extracted from the M-H curves including H-C, magneto-crystalline anisotropy, squareness, and magnetization were found to depend on x. Frequency dependence of capacitance and admittance exhibited a resonance behavior corresponding to the radial mode of the electromechanical resonance (EMR). ME coefficients were studied in both longitudinal (alpha(E33)) and transverse (alpha(E31)) modes. The highest coupling coefficients, alpha(E31) similar to 14.5 mV/Oe.cm and alpha(E33) similar to 13 mV/Oe.cm were obtained for composite with 50 at% NZF at off-resonance frequency of 1 kHz. At the EMR frequency of 314 kHz, the alpha(E31) value in 0.5BCZT-0.5NZFO composite enhanced enormously to similar to 5.5 V/Oe.cm. The studies conclude that x = 0.5 is an optimum atomic fraction of NZFO in the particulate composite for maximum ME coupling.
keywords
DIELECTRIC-PROPERTIES; MAGNETIC-PROPERTIES; XPS SPECTRA; CORE-SHELL; RAMAN; TEMPERATURE; LAMINATE
subject category
Materials Science
authors
Coondoo, I; Vidal, J; Bdikin, I; Surmenev, R; Kholkin, AL
our authors
Groups
G2 - Photonic, Electronic and Magnetic Materials
G6 - Virtual Materials and Artificial Intelligence
Projects
CICECO - Aveiro Institute of Materials (UIDB/50011/2020)
CICECO - Aveiro Institute of Materials (UIDP/50011/2020)
Associated Laboratory CICECO-Aveiro Institute of Materials (LA/P/0006/2020)
acknowledgements
I.C. would like to acknowledge financial assistance by national funds (OE), through FCT -Fundacao para a Ciencia e a Tecnologia, I.P., in the scope of the framework contract foreseen in the numbers 4, 5 and 6 of the article 23, of the Decree-Law 57/2016, of August 29, changed by Law 57/2017, of July 19. This work was partially developed within the scope of the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020, UIDP/50011/2020 & LA/P/0006/2020, financed by national funds through the FCT/MEC (PIDDAC). Support from the Ministry of Science and Higher Education of the Russian Federation is acknowledged (grant agreement #075-15-2021-588 from June 1, 2021). The authors thank Dr. Nitu Kumar, formerly at Department of Physics, University of Puerto Rico, USA for his kind help in magnetic measurements. We are also thankful to Prof. Dillip K. Pradhan, Department of Physics and Astronomy, National Institute of Technology, Rourkela, Odisha 769008, India for his fruitful discussion.