In this review, the state of the art in understanding the structural phase relations in perovskite-structured BiFeO₃-based polycrystalline solid solutions is presented and discussed. Issues about the close relation between the structural phase and overall physical properties of the reviewed systems are pointed out and discussed. It is shown that, by adjusting the structural symmetric arrangement, the ferroelectric and magnetic properties of BiFeO₃-based polycrystalline s...

The polycrystalline samples of complex tungsten bronze (TB) Na₂Pb₂R₂W₂Ti₄V₄O₃₀ (R=Dy, Pr) compounds were prepared by solid-state reaction technique. Room- temperature preliminary structural studies confirm the formation of the compounds in the orthorhombic crystal system. Detailed studies of electrical properties of the materials using complex impedance spectroscopy technique exhibit that the impedance and related pa...

The effect of La³⁺, Mn²⁺ and Ni²⁺ doped calcium copper titanate, CaCu₃Ti₄O₁₂ (CCTO), at higher concentrations (CR1 and CR2 with 5?mol% and 10?mol%, respectively), has been examined by semi-wet route at relatively lower temperature. This semi-wet route employs citrate–nitrate gel chemical method using TiO₂ solid powders. X-ray diffraction (XRD) analysis confirms the formation of single phase in the doped samples sinte...

Bamboo charcoal was expected to be a renewable carbon source for carbide materials in carbothermal reduction because of its superior characteristics. SiC powders with characteristic shapes were fabricated by carbothermal reduction with industrial silica sol and bamboo charcoal particles as silicon and carbon sources respectively, and the effects of reacting temperature and time on shape evolutions and properties of the as-prepared SiC powders were investigated. The silica sol/bamboo charcoal ...

Ni-doped BiFeO₃ powders with the composition BiFe_1-xNi_xO₃ (x = 0.05, 0.1 and 0.15) were prepared by a self-propagating high-temperature synthesis (SHS), using metal nitrates as oxidizers and glycine as fuel. The X-ray diffraction (XRD) patterns depict that Ni-doped BiFeO₃ ceramics crystallize in a rhombhohedral phase. The scanning electron micrographs of Ni-doped BiFeO₃ ceramics show a dense morp...

Piezoelectric ceramics are extensively investigated materials for transducer application. The selection of optimal piezoelectric material for this particular application is a tedious task. It depends upon various physical properties, including piezoelectric charge coefficient (d₃₃), electromechanical coupling factor (K_p), dielectric constant (ε_r), and dielectric loss (tanδ). The classical multiple attribute deci...

Hematite pigment has a long history, but it cannot be used for ceramic application, because it must be thermally and chemically stable at high firing temperature when using a pigment in a glaze or ceramic body. Recently, through encapsulated systems, a new pigment with suitable thermal and chemical stability can be obtained by encapsulating hematite crystals into selected silica or zircon matrices. It means that nano-sized red hematite has been encapsulated into the protected phases. Trans...