2024-03-28T18:10:31Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/1178292019-04-25T07:29:41Zcom_10261_31com_10261_3col_10261_284
Spectroscopic study of the competition between dehydration and carbonation effects in La2O3-based materials
Orera, Alodia
Larraz, G.
Sanjuán, M. L.
Ministerio de Economía y Competitividad (España)
Gobierno de Aragón
European Commission
Consejo Superior de Investigaciones Científicas (España)
Carbonation
Lanthanum hydroxide
Lanthanum carbonates
Raman spectroscopy
Lanthanum oxide
La2O3 takes part in a variety of technologically interesting solids, but it has a known tendency to react with water and CO2, which may result in nonstoichiometry of the final product and the appearance of impurities. We apply Raman spectroscopy to study hydration and carbonation effects of La2O3-based materials, using La(OH)3 as starting material. The thermal evolution of La(OH)3 reflects the competition between dehydration and carbonation kinetics, and thus is highly dependent upon environment and experimental conditions. In vacuum, La(OH)3 evolves first to LaOOH and then to a mixture of C- and A-La2O3 until, upon further heating, only A-La2O3 phase remains. In air, La(OH)3 yields first LaOOH, but under slow heating LaOOH converts to I, Ia and II-type oxycarbonates, in increasing order of thermal stability. II-La2O2CO3, in turn, decomposes to La2O3 at 700°C. Structural relations governing phase conversion within hexagonal or orthogonal-like compounds are discussed. © 2013 Elsevier Ltd.
2015-07-10T11:09:15Z
2015-07-10T11:09:15Z
2013
2015-07-10T11:09:15Z
artículo
Journal of the European Ceramic Society 33(11): 2103-2110 (2013)
http://hdl.handle.net/10261/117829
10.1016/j.jeurceramsoc.2013.03.010
http://dx.doi.org/10.13039/501100003329
http://dx.doi.org/10.13039/501100000780
http://dx.doi.org/10.13039/501100003339
http://dx.doi.org/10.13039/501100010067
eng
Sí
Sí
closedAccess
Elsevier