Fluorination of alumino-silicate minerals: The example of lepidolite

Larisa P. Demyanova (1) , Alain Tressaud (2)

1 Institute of Geology and Nature Management
2 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux

The effect of fluorination on silicate and alumino-silicate minerals has been investigated, in particular on the lepidolite [K(Li,Al)₃ [Si₃AlO₁₀] (F,OH)₂] of the mica-type. The fluorination techniques included direct F₂-gas and cold radio-frequency-plasma involving c-C₄F₈ or O₂/CF₄ mixtures. The modifications of the surface properties have been followed mostly by XPS. Depending of the fluorination route used, either a reactive etching process involving M–F bonding occurs (direct F₂-gas; O₂–CF₄ rf-plasma), or a carbon fluoride deposition takes place (c-C₄F₈ rf-plasma).

Mots clés: Silicate; Mica; XPS; Surface modifications; Fluorine; Rf-plasma; Fluorinated gases

Domaines: Matériaux

Larisa P. Demyanova, Alain Tressaud. Fluorination of alumino-silicate minerals: The example of lepidolite. Journal of Fluorine Chemistry, 2009, 130 (9), pp.799-805. ⟨10.1016/j.jfluchem.2009.06.009⟩. ⟨hal-00419949⟩