Effect of Fe/Ta doping on structural, dielectric, and electrical properties of Bi₄Ti_2.5Fe_0.25Ta_0.25O₁₂ ceramics

Abstract

Aurivillius single‐phase Bi4Ti2.5Fe0.25Ta0.25O12 ceramics was prepared via high‐temperature solid‐state reaction method. The detailed structural analysis of the doped Bi4Ti3O12 compound was carried out by Rietveld refinement of the full XRD Pattern. Dielectric and electrical properties were studied in a wide range of temperature and frequency by dielectric/impedance spectroscopies. The comprehensive analysis of frequency spectrum reveals the occurrence of two relaxation behaviors in the ceramics at low frequency and high frequency, respectively. A phase transition was observed at ~650°C in Bi4Ti2.5Fe0.25Ta0.25O12 somewhat lower than the ferroelectric transition temperature of Bi4Ti3O12. The possible reason for the decrease of ferroelectric transition temperature was discussed based on the structural analysis. The present results could be useful for designing and/or modifying properties of Bi4Ti3O12‐related ceramics.

Origin of Multiferroism of Ion Doped at Different Sites: Bi4Ti3O12 Bulk and Nanoparticles

“…We find for x = 0.25 T FM C = 340 K, again in good quantitative agreement. From Figure 3, curve 2, one realizes that T FE C decreases with increasing Fe dopants, likewise in agreement with Paul et al [30] and Rehman et al [9] where here in [9] one finds for x = 0.25, a value of T FE C of 923 K. Our observed value is 920 K, that is, a surprising quantitative accordance.…”

“…The dielectric properties of bulk BiT were also studied in refs. [8–10]. The ferroelectric and dielectric properties of Sm‐ and La‐codoped, Eu‐, Mn‐, and Nd‐doped BiT thin films are observed by Du et al [ 11 ] Pei et al [ 12 ] Li et al [ 13 ] of Nd‐substituted BiT nanoparticles (NPs) by Marikani et al [ 14 ] and of Zr‐doped BiT ceramic by Subohi et al [ 15 ]…”

Archives of Metallurgy and Materials

“…Meanwhile, at the high frequency, it's found to be around 0.09 when measured at 1 MHz. the sharp drop of dielectric constants at low frequency is mainly due to space charges [11]. the evolution of these two dielectric parameters seems to be independent of doping which could be attributed to the grain size and the density of the ceramics [12].…”

Progress and Perspectives on Aurivillius-Type Layered Ferroelectric Oxides in Binary Bi4Ti3O12-BiFeO3 System for Multifunctional Applications

“…The ion substitution would influence the inter-strain and tolerance factor. The A-site can be occupied by large cations such as Na + [20], K + [107], Ca 2+ [108], Sr 2+ [46], Ba 2+ [26], Pb 2+ [109], Y 3+ [21], Bi 3+ and Ln (La [27], Nd [22], Sm [23], Gd [24], Ce [110][111][112],Tb [25], Dy [113], Ho [114], Er [115,116], Eu [56], Yb, Th [117], Pr [118]), the B-site can accommodate hetero-valent elements (Ti 4+ , W 6+ [36], Nb 5+ [43], Ta 5+ [119], V 5+ , Cu 2+ [120], Mo 6+ [121], and Mg 2+ [43]) and a variety of magnetic elements (Fe, Cr, Mn, Co, and Ni) [32][33][34][35][36][37][38][39][40][41][42][43][44]52], which will create the possibility of magnetic ordering. More interestingly, the halogen or nitrogen elements substitution on the O-sites was accomplished [122,123].…”