Study of the structural, ferroelectric and dielectric properties of BaTiO3 co-doped with Sn4+ and Cr3+

Abstract

In the present work, we studied the effect of Sn⁴⁺ and Cr³⁺ doping on the structural, ferroelectric, and dielectric properties of BaSn_xCr_yTi_1−(x+y)O₃. The materials were prepared by a combination of high-energy mechanical milling and solid-state reactions. The X-Ray Diffraction (XRD) analysis and Rietveld refinements confirmed the presence of a single tetragonal phase for the pure and doped samples. The SEM study revealed that the microstructure is highly susceptible to the addition of both dopants, causing an evident grain refinement. On the other hand, the addition of Sn⁴⁺ and Cr³⁺ had a strong influence on ferroelectric properties, as observed by the pinching of the ferroelectric hysteresis loops. The addition of Sn⁴⁺ increases the remnant and maximum polarization, as the Cr³⁺ doping promoted the contrary effect. Co-doping with Sn⁴⁺ and Cr³⁺ resulted in a maximum energy storage value of 0.2574 J/cm³ with a efficiency of up to 65%, overcoming the values of pure BT. The relative permittivity of all doped samples remained in values of ∼1000, just a little below the permittivity of pure BT.