Dielectric relaxation to assess surface properties of aluminosilicates

A sample of aluminosilicate, natural or synthetized, that contains exchangeable cations, call be polarized by the application of an electric field. In this work, we show that the current measured when ehs sample is depolarized under non-isothermal treatment (thermally stimulated depolarization current spectroscopy) can lead to assess the chemical potential of the electrons in the anionic network where cations carl be embedded. This original and quantitative approach does not require ab initio calculations but allows us to characterize the heterogeneity of aluminosilicate surfaces. The first results are obtained on a mordenite exchanged with different Na+ exchange degrees. (C) Academie des sciences/Elsevier, Paris.