Electrical and Physical Characterization of Bulk Ceramics and Thick Layers of Barium Titanate Manufactured Using Nanopowders

Abstract

International audienceFine powders of BaTiO3 are synthesized by hydrothermal processing at 250 C for 7 h. Two different starting mixtures were used, TiCl3 + BaCl2 and TiO2 + BaCl2. The size of the resulting crystallites was close to 20 nm in both cases. The powders were formed into ceramic pellets or thick layers. The samples were characterized for microstructure and electrical permittivity. The impact of the microstructure on the electrical properties is emphasized, and is correlated to the powder characteristics and the powder realization process

Colossal permittivity and low losses in Ba1–Sr TiO3– reduced nanoceramics

“…In a previous work [18], the presence of residual carbon due to SPS processing technique was determined through the spectrometric quantification of CO 2 and appeared to be very low with a concentration of 93 ppm. Samples appeared dark blue, consistent with the presence of Ti 3+ caused by the reducing atmosphere used during SPS (low vacuum and carbon environment) as previously demonstrated using X-ray photoelectron spectroscopy (XPS) [25]. SPS pellets were finally annealed for 15 min at 850 • C in an oxidizing atmosphere in an attempt to partially restore the oxygen stoichiometry.…”

Multifunctional BaTiO3‐(Bi0.5Na0.5)TiO3‐based MLCC with high‐energy storage properties and temperature stability

“…Recently, there are numerous studies regarding the dielectric properties and temperature stability of BaTiO 3 ‐based ceramics. Nguyen et al has prepared bulk ceramics and thick layers of BaTiO 3 to characterize their electrical and physical properties, while energy storage performance was not reported in their work. The low dielectric breakdown strength of BaTiO 3 ‐based bulk ceramics often leads to a small energy storage density and the large hysteresis leads to low energy‐efficiency.…”

Multiscale Characterization and Model for the Dynamic Behavior of Ferroelectric Materials Using Fractional Operators

“…The fractional derivative generalizes the concept of derivative to non-integer orders. The fractional derivative of a smooth (arbitrary) function g(t) is defined through a convolution between g(t) function and t α (t)/ Ŵ(1 − α) where Ŵ(α) is the gamma function; α, the order of fractional derivation; and (t) is the step Heaviside function (see [12], while a summary of various representations can be found in [18]). After addition of fractional terms in our simulation, the model equations (Eqs.…”