Regular Article

Na-doping approach for conductivity enhancement of natural phosphate derived fluorapatites

¹ Laboratory of Applied Chemistry of Materials, Faculty of Science, Mohammed V University in Rabat, Avenue Ibn Batouta BP.1014, Rabat, Morocco
² MASCIR Foundation, VARENA Center, Rabat Design, Rue Mohamed El Jazouli, Madinat Al Ifran, 10100 Rabat, Morocco
³ Department of Physics, Engineering Physics and Astronomy, Queen’s University, Kingston, Ontario, Canada
⁴ Laboratoire de Catalyse, Chimiométrie et Environnement, URAC 24, Faculté des Sciences et Techniques Mohammedia, Université Hassan II de Casablanca, B. P. 146, 20650 Rabat, Morocco

^* e-mail: laghzizi@fsr.ac.ma

Received: 24 May 2022
Received in final form: 24 June 2022
Accepted: 19 July 2022
Published online: 30 August 2022

Abstract

The search for thermally stable solid electrolytes is promising for solid-state batteries. High ionic conductivity solid electrolytes derived from natural phosphate modified by sodium addition were developed. The samples were characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, ²³Na solid-state nuclear magnetic resonance and scanning electron microscopy with energy dispersive spectroscopy. The structural and morphology changes were observed by increasing the Na₂SO₄ content. The synthesized ceramic electrolytes have low activation energy of about 0.60 eV and a relatively high ionic conductivity of 2 × 10⁻² mS cm⁻¹ at 400 °C.