Electrical and electrochemical properties of Li2M(WO4)2 (M = Ni, Co and Cu) compounds

Karim Karoui; Abdelfattah Mahmoud; Abdallah Ben Rhaiem; Frèdéric Boschini

doi:10.1039/c8ra10306b

Electrical and electrochemical properties of Li₂M(WO₄)₂ (M = Ni, Co and Cu) compounds

RSC Adv. 2019 Feb 27;9(12):6785-6792. doi: 10.1039/c8ra10306b. eCollection 2019 Feb 22.

Authors

Karim Karoui¹, Abdelfattah Mahmoud², Abdallah Ben Rhaiem¹, Frèdéric Boschini²

Affiliations

¹ Laboratory of Condensed Matter, Faculty of Science of Sfax, University of Sfax BP1171 - 3000 Sfax Tunisia karouikarim36@yahoo.com.
² GREENMAT, CESAM Research Unit, University of Liege Chemistry Institute B6, Quartier Agora, Allée du 6 août, 13 B-4000 Liege Belgium.

Abstract

Li₂M(WO₄)₂ (M = Co, Cu or Ni) materials have been synthesized using the solid-state reaction method. X-ray diffraction measurements confirmed the single phase of the synthesized compounds in the triclinic crystal system (space group P1̄). The SEM analyses revealed nearly spherical morphology with the particle size in the range of 1-10 μm. The IR spectra confirm the presence of all modes of WO₄ ^2-. The impedance spectroscopy measurements showed the presence of grain boundaries and allow determination of the conductivity of the synthesized materials at room temperature. As positive electrode materials for lithium ion batteries, Li₂M(WO₄)₂ (M = Co, Cu or Ni) cathode materials deliver initial discharge capacities of 31, 33 and 30 mA h g^-1 for cobalt, nickel, and copper, respectively.