I really appreciate your answer. Sorry for not posting the question correctly, or with little data. The point is that I start from a well crystallized phase (perovskite) that, when put into electrolyte (acidic media), loses cations and becomes amorphous, leaving Ir, O and only a small fraction of the other atoms.
In the SAED there are three diffuse rings so the domains must be small. The resulting phase is quite active in the reaction, so, It would be interesting to know what happens here. I can't identify
the structure with just those three rings either, so I go blind. The subject with several phases comes from this paper: E. Willinger et al. J. Am. Chem. Soc. 2017, 139, 34, 12093–12101 , where they identify in the IrOx
the presence of hollandite together with rutile-type IrO2 through electron diffraction and PDF analysis. In my case I am supposing that the starting structure remains with disorder and some related candidates may appear, for example IrO2 and/or Ir metallic,.but I do not know if this is possible or the problem is so complex and not able to fit it. I send you the SAED pattern and also the PDF file obtained from it.
I hope this may clarify what I mean.
Thanks a lot for your time and your consideration,