Synthesis and characterization of niobium doped bismuth titanate | Síntesis y caracterización del titanato de bismuto dopado con niobio

Abstract

Pure and niobium doped bismuth titanate ceramics Bi4Ti3−xNbxO12(Nb − BiT) with x ranging from 0% to 2% are prepared by sol–gel method. Pellets are sintered by pressureless sintering (PLS) and spark plasma sintering (SPS). Raman spectroscopy indicates distortion in the structure due to the substitution of titanium by niobium. X-ray photoelectron spectroscopy (XPS) displays the Nb integration to the bismuth titanate ceramic structure. X-ray diffraction shows no secondary phases and offers clues about crystallographic texturing due to the SPS technique. The shape and size of the grains are strongly influenced by the niobium added to the system as reported by scanning electron microscopy. Ferroelectric hysteresis loops exhibit the effect of the niobium and the texturing on the ferroelectric behavior. Higher values of remanent polarization are reported for PLS samples. In comparison with PLS, higher values ofthe relative permittivity are reported for SPS samples due to the non-homogeneous incorporation of Nb