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Abstract: Tetragonal Li7La3Zr2O12 (LLZ) was synthesised by the solid-state and citrate–nitrate methods. The crystal structure of the samples was characterised by the X-ray diffraction method. The morphology of the particles was investigated using both optical microscopy and a particle size analysis method. The ceramic samples were studied by complex impedance spectroscopy in the frequency range from 12 to 105 Hz, in the temperature range of 20–400°C. Synthesis by the citrate–nitrate method makes it possible to reduce both the temperature and time of the synthesis and also prepare the product with smaller particles. The conductivity of LLZ synthesised by the citrate–nitrate method (5.2×10−6 Scm−1 at 20°C) is higher than the conductivity of LLZ synthesised by the solid-state method (1.3×10−6 Scm−1 at 20°C). [Copyright &y& Elsevier]

Electron and ion transfer numbers, electroconductivity, density, and concentrations of Cu+ and Cu2+ in molten salt mixtures of CuCl–CuCl2–MeCl (Me=Li, Na, K, Cs) were measured at a partial pressure of chlorine over the melt equal to the atmospheric pressure in the temperature interval from 800 to 1000 K. Partial values of ion and electron transfers and the molar volume of the melts were determined. Mobility of electrons was estimated. The electron transfer number was a maximum in the CuCl–CuCl2 melt with tc equal to 0.9. When chlorides of alkali metals were added to the CuCl–CuCl2 melt, the electron component of electroconductivity was preserved up to 90, 65, 60, and 50 mol.% LiCl, NaCl, KCl, and CsCl, respectively. A mechanism of the electron transfer in the test melts was proposed. [Copyright &y& Elsevier]