Green coloration of Co-doped ZnO explained from structural refinement and bond considerations

Manuel Gaudon (1) , Olivier Toulemonde (1) , Alain Demourgues (1)

1 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux

ZnO doped with Co2+ has been prepared by a Pechini process and investigated in terms of crystallographic structure and UV-visible properties. We emphasize for the first time a splitting of the ZnO band gap in two "sub-band gaps" (never clearly mentioned until now) which is fully interpreted basing on the iono-covalent nature of the O-Zn bonds. An anticipative approach of the potential structure relaxations was discussed from exchanged effective charge per bond calculated with the purely ionic Brown and Altermatt model.

Mots clés: Electric charge; Color; UV and visible spectra; Bond length; Band gap; Zinc oxide; Cobalt(2+)

Domaines: Matériaux

Manuel Gaudon, Olivier Toulemonde, Alain Demourgues. Green coloration of Co-doped ZnO explained from structural refinement and bond considerations. Inorganic Chemistry, 2007, 46 (26), pp.10996-11002. ⟨10.1021/ic701157j⟩. ⟨hal-00229843⟩