New investigations on the surface reactivity of layered lithium oxides

Nathalie Andreu (1) , Isabelle Baraille (1) , Hervé Martinez (1) , Rémi Dedryvère (1) , Michel Loudet (1) , Danielle Gonbeau (1)

1 IPREM - Institut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux

Density Functional Theory is applied to understand the large difference in surface reactivity of LiCoO 2 due to Al/Co substitution which is experimentally observed. In this way, we explore the SO 2 and CO 2 adsorption modes on the (110) surface of LiCoO 2 and α-LiAlO 2. For SO 2 adsorption, chemisorption produces sulfite species (for LiCoO 2 and α-LiAlO 2) and sulfate species (in the case of LiCoO 2). We demonstrate that the modification of the surface reactivity when Co 3+ ions are substituted by Al 3+ ions is due to a change from an adsorption mode controlled by redox properties for LiCoO 2 to a less energetically favorable adsorption mode controlled by acid-base properties for α-LiAlO 2. For CO 2 adsorption, the formation of carbonate species is observed for both compounds, illustrating the fundamental difference in the factors controlling SO 2 adsorption compared to CO 2 adsorption.

Mots clés: Lithium alloys; Lithium oxides; Redox property; Density functional theory; Surface reactivity; Sulfate species; Sulfur dioxide; Acid-base property; adsorption; Adsorption modes; Carbonate species; Carbon dioxide; Chemisorption

Domaines: Chimie; Matériaux

Nathalie Andreu, Isabelle Baraille, Hervé Martinez, Rémi Dedryvère, Michel Loudet, et al.. New investigations on the surface reactivity of layered lithium oxides. Journal of Physical Chemistry C, 2012, 116 (38), pp.20332-20341. ⟨10.1021/jp304293u⟩. ⟨hal-01498387⟩