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Abstract: In this paper, we report on the low temperature solution reduction method employed in the synthesis of large quantities of nano/micro-sized bismuth (Bi) crystals with sodium hypophosphite (NaH2PO2·H2O) as reductant in acidic solutions. The achieved Bi crystals exhibited plate-like (100nm in size and few nanometers in thickness) or polyhedral (500nm in size) shapes. Bi nanocrystals transformed to octahedron-like Bi microcrystals only by prolonging the reaction time. The assembly and oriented growth should be the reason. To understand the growth mechanism, we also discussed the possible growth of the Bi nanocrystals exhibits influence of experimental parameters such as reaction time, NaH2PO2·H2O concentration, and pH value. The resulting Bi crystals were characterized by using scanning electron microscopy, X-ray powder diffraction and differential thermal analysis and thermogravimetry. Optical properties of the samples were studied by ultraviolet–visible spectroscopy. [Copyright &y& Elsevier]

Abstract: The Aurivillius type bismuth layer-structured compound potassium lanthanum bismuth titanate (K0.5La0.5Bi4Ti4O15) is synthesized using conventional solid-state processing. The phase analysis is performed by X-ray diffraction (XRD) and the microstructural morphology is conducted by scanning electron microscopy (SEM). The ferroelectric, dielectric and piezoelectric properties of K0.5La0.5Bi4Ti4O15 (KLBT) ceramics are investigated in detail. The remnant polarization (P r) and coercive field (E c) are found to be 8.6μCcm−2 and 60kVcm−1, respectively. The Curie temperature T c and piezoelectric coefficient d 33 are 413°C and 18pCN−1, respectively. [Copyright &y& Elsevier]