In chemistry and materials science, the term LAMOX stands for lanthanum molybdenum oxide. In particular, the name LAMOX refers to a material with compositional formula La2Mo2O9.
LAMOX is a fast oxygen ion (O2-) conductor. It undergoes a structural phase transition from the nonconductive monoclinic form to the highly conductive cubic form at a temperature of about 580 °C.
In fact, LAMOX is the parent of a whole family of oxides, whose members are derived by substituting some of the lanthanum atoms by strontium, barium, potassium, or bismuth atoms and/or some of the molybdenum atoms by rhenium, sulfur, tungsten, chromium, vanadium, niobium, or tantalum atoms. In some of those modified LAMOX compounds the phase transition is suppressed and the anion-conducting phase is stabilized, even at room temperature.
Keywords: oxide-ion conductor, solid solutions, conductivity of anions, crystal structure, local disorder, variable compound composition
Selected references
[1] F. Goutenoire, O. Isnard, E. Surad, O. Bohnke, Y. laligant, R. Retoux and Ph. Lacorre: Structural and transport characteristics of the LAMOX family of fast oxide-ion conductors, based on lanthanum molybdenum oxide La2Mo2O9. J. Mater. Chem. 2001, 11, pp. 119-124. DOI: 10.1039/b002962i.
[2] S. Georges, F. Goutenoire, O. Bohnke, M. C. Steil, S. J. Skinner, H.-D. Wiemhöfer and P. Lacorre: The LAMOX Family of Fast Oxide-Ion Conductors: Overview and Recent Results. Journal of New Materials for Electrochemical Systems 2004, 7, pp. 51-57. PDF version.
[3] L. Malavasi, H.-J. Kim, S. J. L. Billinge, T. Proffen, C. Tealdi and G. Flor: Nature of the Monoclinic to Cubic Phase Transition in the Fast Oxygen Ion Conductor La2Mo2O9 (LAMOX). J. Am. Chem. Soc. 2007, 129, pp. 6903-6907. DOI: 10.1021/ja071281e.
[4] Z.S. Khadasheva, N. U. Venskovskii, M. G. Safronenko, A.V. Mosunov, E.D. Politova and S. Y. Stefanovich: Synthesis and Properties of La2(Mo1-xMx)2O9 (M = Nb, Ta) Ionic Conductors. Inorg. Mat. November 2002, 38 (11), pp. 1168-1171.
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