A comparative study of Li1-xMn2-xO4 (0 <= x <= 0.08) by means of anelastic spectroscopy and differential scanning calorimetry (DSC) is reported. DSC measurements, in agreement with previous literature, can detect a phase transition accompanied by latent heat only for x < 0.04. This fact has been generally accepted as a proof that the transformation is suppressed by doping. In this paper we show that DSC alone is not sufficient to provide a correct answer to the problem. Indeed, anelastic spectroscopy, which is a technique extremely sensitive to rearrangements of atoms in the lattice, indicates that the transition survives up to x = 0.08, is shifted towards lower temperatures, and becomes of an order higher than the first, so that there is no associated latent heat. (c) 2006 Elsevier B.V. All rights reserved.
Doping effects on the phase transition of LiMn(2)O(4)by anelastic spectroscopy and differential scanning calorimetry
Paolone A;Ferretti M;
2006
Abstract
A comparative study of Li1-xMn2-xO4 (0 <= x <= 0.08) by means of anelastic spectroscopy and differential scanning calorimetry (DSC) is reported. DSC measurements, in agreement with previous literature, can detect a phase transition accompanied by latent heat only for x < 0.04. This fact has been generally accepted as a proof that the transformation is suppressed by doping. In this paper we show that DSC alone is not sufficient to provide a correct answer to the problem. Indeed, anelastic spectroscopy, which is a technique extremely sensitive to rearrangements of atoms in the lattice, indicates that the transition survives up to x = 0.08, is shifted towards lower temperatures, and becomes of an order higher than the first, so that there is no associated latent heat. (c) 2006 Elsevier B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
