what is the characteristic of 0.226
Answers
Explanation:
Polycrystalline Ca0.18Sr0.226Ba0.594Nb2O6 (CSBN18) was synthesized via the solid-state reaction route. X-ray structural studies confirmed it belonged to the tetragonal tungsten bronze family. Rietveld refinement of the X-ray data has been carried out for CSBN18 where the atomic positions and site occupancy factors for A-sites have been determined. The dielectric properties of CSBN18 ceramic were studied as a function of temperature in the 100 Hz–1 MHz frequency range. The dielectric relaxation followed the Vogel–Fulcher relation wherein Ea = 37.4 meV; Tf = 131.5 °C and ω0 = 4.31 × 10⁹ rad s⁻¹. A high pyroelectric coefficient of ∼ 250 μC m⁻².K was obtained around the transition temperature (∼150 °C). This is significantly higher than that reported for polycrystalline SrxBa1-xNb2O6 (SBN). However, the piezoelectric coefficient (d33) of the title composition was as low as 6 pC N⁻¹.