Synthesis of Eu³⁺‐doped BaBi₂Ta₂O₉ based glass‐ceramic nanocomposites: Optical and dielectric properties

Abstract

In this paper we report for the first time synthesis of Eu3+‐doped transparent glass‐ceramics (TGC) with BaBi2Ta2O9 (BBT) as the major crystal phase using the glass system SiO2–K2O–BaO–Bi2O3–Ta2O5 by melt quenching technique followed by controlled crystallization through ceramming heat treatment. DSC studies were conducted in order to determine a novel heat‐treatment protocol to attain transparent GCs by controlling crystal growth. The structural properties of the BBT GCs have been investigated using XRD, FE‐SEM, TEM and FTIR reflectance spectroscopy. Optical band gap energies of the glass‐ceramic samples were found to decrease with respect to the precursor glass. An increased intensity of emission along with increase in the average lifetime of Eu3+ was observed due to incorporation of Eu3+ ions into the low‐phonon energy BBT crystal site. The local field asymmetric ratios of all the samples were observed greater than unity. The dielectric constant (εr), dielectric loss, and dissipation factor values of both the base glass and ceramized samples were found to decrease with increase in frequency.

Synthesis, optical, and magnetic properties of six‐layered Aurivillius bismuth ferrititanate

“…Bi‐based compounds have drawn a lot of attention because for their potential application as novel photocatalysts, in which the lone pair electrons of Bi 3+ ere are often found to possess hybridized band structures . Especially, Aurivillius compounds have been widely reported because of its special layer perovskite atom arrangements and favourable optical band structure . Also, many kinds of Aurivillius photocatalysts have been intensively investigated in water splitting and photocatalytic degradation of organic dyes …”