ChemInform Abstract: NaMnFe2(PO4)3 Alluaudite Phase: Synthesis, Structure, and Electrochemical Properties As Positive Electrode in Lithium and Sodium Batteries.

✍ Scribed by Khiem Trad; Dany Carlier; Laurence Croguennec; Alain Wattiaux; Mongi Ben Amara; Claude Delmas

• Publisher: John Wiley and Sons
• Year: 2010
• Weight: 19 KB
• Volume: 41
• Category: Article
• ISSN: 0931-7597
• DOI: 10.1002/chin.201049020

✦ Synopsis

NaMnFe 2 (PO 4 ) 3 Alluaudite Phase: Synthesis, Structure, and Electrochemical Properties As Positive Electrode in Lithium and Sodium Batteries. -The title compound is prepared by solid state reaction of Na2CO3, MnCO3, FeC2O4, and NH4H2PO4 at 900 °C, and by the Pechini sol-gel method starting with stoichiometric mixtures of the same educts in aqueous solutions containing citric acid (800 °C, 30 min). The samples are characterized by XRD and neutron diffraction, SEM, Moessbauer spectroscopy, and DFT calculations. The compound obtained by the Pechini method has the composition Na0.95Mn1.09Fe2.02(PO4)3. All the prepared samples crystallize in the monoclinic space group C2/c. The three-dimensional skeleton structure exhibits two types of one-dimensional tunnels where the Na + ions are located. The samples prepared by the sol-gel method exhibit much better performances as positive electrodes in lithium cells. The material can intercalate 1.5 Li + ions per formula unit at low rate.