Na-doping approach for conductivity enhancement of natural phosphate derived fluorapatites Ikrame Es-saidi, Jihane Labrag, Abdelaziz Laghzizil, Karim Dânoun, Jean-Michel Nunzi and Mohamed Zahouily Eur. Phys. J. Appl. Phys., 97 (2022) 58 Published online: 30 August 2022 DOI: 10.1051/epjap/2022220156