Formation of interfacial nano-layers in the system Pt-Ni-O

Solid state electrochemical cells have been applied to oxidize Pt-Ni alloys and NiO in contact with Pt. The resulting interfaces have been analyzed by analytical transmission electron microscopy. Highly oxidized phases and co mplex morphologies have been identified on a nanometer scale in both cases. These phenomena are discussed in the context of solid state pattern format ion and characteristic reactions of the system Pt-Ni-O, such as alloy oxida tion and reactions between NiO and Pt. Reaction and diffusion mechanisms, w hich can explain the formation of the complex microstructures, are introduc ed for each case. (C) 2001 Elsevier Science B.V. All rights reserved.