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Vivianite and Beraunite

  • Pier Paolo Prosini
Chapter

Abstract

Wet chemical methods, such as the hydrothermal, template, and precipitation process provide effective-cost preparation techniques, especially if compared to “high-temperature” methods (Dominkó et al., J Power Sour. 153, 274–280, 2006; Yang et al., Electrochem. Commun. 3, 505–508, 2001; Zhang et al., Funct. Mater Lett. 3, 177–180, 2010; Palomares et al., J. Power Sour. 171, 879–885, 2007). Liquid-phase synthesis has the advantage to be carried out at low temperatures (low energy), to be flexible and controllable and to give materials with homogeneous nano-particle structures. An obvious disadvantage of the synthesis in liquid phase is that the so-obtained materials show low density. In this chapter a sol–gel route to prepare iron (II) phosphate is reported. Synthetic vivianite (Fe3(PO4)3×nH2O) (Scaccia et al., Thermochim. Acta. 397, 135–141, 2003) was obtained by adding phosphate ions to a solution of Fe2+. It is well known that natural ferrous phosphate (vivianite) rapidly oxidizes on exposure to air, passing through deepening shades of blue to finally become brown beraunite (3Fe2O3•2P2O5•10H2O). The vivianite obtained by the sol–gel route was dried in air at 100°C. The so-obtained material was characterized by TG/DTG/DTA, XRD, SEM and Mössbauer spectroscopy and its electrochemical behavior as a cathode in a non-aqueous lithium cell was evaluated (Prosini et al., J. Electrochem. Soc. 148, A1125–A1129, 2001) .

Keywords

Active Material Iron Phosphate Composite Cathode Ferrous Phosphate Phosphate Aqueous Solution 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media, LLC  2011

Authors and Affiliations

  1. 1.Renewable Technical Unit, C.R. CasacciaENEARomeItaly

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