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The temperature dependence of magnetization and dielectric constant of polycrystalline Ba3NbFe3Si2O14 clearly indicates the presence of magnetically driven ferroelectric transition at 26 K, the Néel temperature TN, depicting its multiferroic behavior. The isothermal magnetization variation with the field both below and above TN however exhibits a hysteresis behavior with coercivity varying from 1600 Oe to 2500 Oe. These results combined with structural studies indicate the presence of multiple phases which are electronically and not structurally phase separated, similar to the phenomenon observed in magentoresistive perovskite compounds. [ABSTRACT FROM PUBLISHER]

The bismuth-layered ferroelectric (BLF) oxides are promising photocatalysts due to their wide band gap, photo-coupled ferro properties, Pb-Free composition, and excellent chemical stability. In this study, polycrystalline SrBi 4 Ti 4 O 15 (SBT) is used as the target photocatalyst, and its photocatalytic performance was evaluated in terms of Rhodamine-B dye degradation under UV light. Moreover, the influence of metal deposition (Ag, Zn, Fe, and Bi) was also explored. The powders of SBT and its metal-decorated derivatives were synthesized and structural, compositional, and optical properties were studied in detail using XRD, XPS, EDS, FTIR, UV–Vis, Raman, and PL spectroscopy. The pristine SBT powders showed 19% photodegradation after 60 min of exposure to UV radiation. Metal nanoparticles deposited on the surface of the SBT were found to improve photocatalytic capacity and a nearly threefold increase (53%) in degradation rate was achieved for Bi-decorated SBT. The rate constant and the turnover frequency are 0.01336 min - 1 and 13.2 × 10 - 3 mol Rh - B mol metal h - 1 , respectively. The degradation was observed to follow a Langmuir–Hinshelwood (LH) model, indicating that the process is first order. [ABSTRACT FROM AUTHOR]