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FERROELECTRIC materials have received great attention for their use in the nonvolatile ferroelectric random access memory (FeRAM) and storage devices.[1,2] Among these ferroelectrics, lead-based perovskite ferroelectric materials have been studied extensively due to their high dielectric constant, piezoelectric coefficient, large remnant polarization (Pr), moderately low coercive field (Ec), and high Curie temperature.[3–6] However, these ferroelectric materials suffer serious polarization fatigue problems and also have drawbacks considering the environmental issue.[7–10] Therefore, it is necessary to develop environmentally-friendly lead-free ceramics and become one of the main trends in the present development of piezoelectric materials. In this new branch of interest, Bismuth-layered perovskite material possesses an important position because of its good ferroelectric properties, including moderate remnant polarization, low coercive PRIYAMBADA NAYAK, RANJIT PATTANAYAK, Research Scholars, and SIMANCHALO PANIGRAHI, Senior Professor, are with the Department of Physics, National Institute of Technology, Rourkela 769008, Odisha, India. Contact e-mail: spanigrahi@nitrkl. ac.in TANMAYA BADAPANDA, Professor, is with the Department of Physics, C.V. Raman College of Engineering, Bhubaneswar 752054, Odisha, India. AVINNA MISHRA, Research Scholar, and SHAHID ANWAR, Scientist, are with the Colloids & Materials Chemistry, Institute of Minerals and Materials Technology, Bhubaneswar, Odisha 751013, India. PRATAP SAHOO, Professor, is with the School of Physical Science, National Institute of Science Education and Research (NISER), Bhubaneswar, Odisha, India. Manuscript submitted July 19, 2013. METALLURGICAL AND MATERIALS TRANSACTIONS A

field, long retention, and low tendency to imprint high fatigue resistance, and its ability to withstand 1012 erase/ rewrite operations.[11] These excellent properties make the Bismuth-layered perovskite materials a very attractive candidate for nonvolatile FeRAM application.[12–14] Bismuth-layered structure ferroelectrics belong to a multilayer family of the so-called Aurivillius phase with a general chemical formula (Bi2O2)2+(Am1BmO3m+1)2, where A represents the 12-fold coordinated cation with low valence in the perovskite sublattice; B denotes the octahedral site with high valence and m refers to the number of BO6 octahedra between neighboring Bi2O2 layers along the c-axis.[14] These BO6 octahedra exhibit spontaneous polarization and (Bi2O2)2+ layers act as the insulating paraelectric layers and mainly control the electrical response such as electrical conductivity, while the ferroelectricity arises mainly in the perovskite blocks.[15,16] Recently, lot of attention has been paid to SrBi4Ti4O15 (SBT) due to its high Curie temperature, low coercive field, barrier type property, large retentivity, and anisotropic physical properties. Various techniques have been used for the preparation of SBT.[17–24] Among them one of the well-known method is the solid-state reaction method with the expectation th