Thallium ionic conductivity of new thallium indium hafnium molybdate ceramics

Abstract

In the process of studying the system Tl 2 MoO 4 -In 2 (MoO 4 ) 3 -Hf(MoO 4 ) 2 , a new thallium indium hafnium molybdate was found. The crystal structure of the molybdate Tl 5 InHf(MoO 4 ) 6 was determined in the centrosymmetric space group R c (a = 10.63893 (5) Å, c = 38.1447(3) Å; V = 3739.04 (4) Å 3 , Z = 6). The structure is a framework consisting and contains alternating mixed (Hf,In)O 6 octahedra connected by MoO 4 tetrahedra. The structure is a three-dimensional framework consisting of alternating (Hf,Fe)O 6 -octahedra connected by МоО 4 -tetrahedra. Each octahedron has common vertices with tetrahedra. The atoms arranged in this way form channels extended along with the a and b axes, in which thallium atoms are located. The conductivity behavior of Tl 5 InHf(MoO 4 ) 6 ceramics was studied in the temperature range from 300 K to 870 K. The conductivity of the heavy cations of thallium is activated with increasing temperature.

Structural, Spectroscopic, Electric and Magnetic Properties of New Trigonal K5FeHf(MoO4)6 Orthomolybdate

“…The resistance decreases with the increasing temperature and the conductivity increases accordingly. This behavior is a characteristic of solid electrolytes, and it is in a good agreement with the results reported previously for selected oxides [ 21 , 72 , 73 , 74 ].…”

“…The electrical properties of K 5 FeHf(MoO 4 ) 6 were investigated by impedance spectroscopy. This is a reliable technique to study the electrical properties of the oxide compounds [ 21 , 67 , 68 , 69 , 70 , 71 , 72 , 73 , 74 ]. The Nyquist plots (Z″ vs. Z′), recorded for the K 5 FeHf(MoO 4 ) 6 sample at different temperatures, are shown in Figure 12 .…”