Electrical properties and alkali-pathways simulation of new mixed conductor Na₄Li_0.62Co_5.67Al_0.71(AsO₄)₆

Abstract

Polycrystalline sodium lithium-cobalt-aluminum arsenate, Na 4 Li 0.62 Co 5.67 Al 0.71 (AsO 4 ) 6 , was synthesized by solid state reaction route and characterized by infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The title material is a member of β-Xenophyllite family which show 3D anionic framework with interconnecting tunnels where alkali-ion are located. Dense ceramic with relative density of 97% is obtained after planetary grinding of the synthesized powder followed by optimal sintering at 1113 K. The effect of grinding on microstructure of sample is controlled by Scanning Electron Microscope (SEM). The electrical study using impedance spectroscopy, in the 443-773 K temperature interval, show interesting electrical performance of the dense ceramic: σ 433K =1.41 10 -5 Scm −1 and the activation energy Ea=0.449 eV. The alkali migration pathways in the anionic framework were simulated using Bond Valence Site Energy (BVSE) model to correlate structure with electrical properties of the studied material. The calculation results were compared to other β-Xenophyllite materials.

Synthesis Methods in Solid-State Chemistry

“…The number of acting parameters is relatively few but difficult to control. This method is commonly used for the synthesis of the single crystals and polycrystalline powders of phosphates and arsenates of transition metals and monovalent cations [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17].…”

Xenophyllite, Na4Fe7(PO4)6, an Exotic Meteoritic Phosphate: New Mineral Description, Na-ions Mobility and Electrochemical Implications

“…The last reported phosphate of a series, RbNa 3 Mg 7 (PO 4 ) 6 , was found to be a promising host matrix for the development of luminophore materials [25,26]. A series of structurally similar phosphates and arsenates was also reported, many of them being Na-ion conductors [27][28][29][30][31][32][33]. 1 Xenophyllite subcell was transformed to cba-setting for a better comparability with other compounds.…”

Structure, thermal stability and electrical properties of cellulose‐6‐phosphate: development of a novel fast Na‐ionic conductor

“…Since the discovery of sodium superionic conductor materials, new sodium‐based conductors have witnessed an increase in research interest, especially in materials chemistry 9 . Indeed, in terms of the physical properties of sodium‐based conductors, especially ionic conduction and ion exchange, these sodium‐based conductors have various interesting applications, such as cathode and anode materials in Na‐ion batteries 10,11 . Some cellulose‐based materials also show interesting electrical properties.…”