The stability of vapour deposited Pt and Pd as electrocatalysts on fluorine
doped, tin oxide coated glass for the use as counter electrodes in dye sen
zitized electrochemical solar cells has been investigated. The electrocatal
ytically active layers did not seem to be chemically stable in an electroly
te consisting of LiI and I-2 dissolved in methoxy propionitrile. Thermodyna
mical calculations suggest the dissolution of Pt and Pd from the electrode
surface to be caused by the formation of PtI4 and PdI6. Formation of comple
x species as PtI42- and PdI42- is less thermodynamically favoured, but PtI4
2- may also be present in the solution. (C) 2000 Elsevier Science B.V. All
rights reserved.