The lattice frings somehow similar to those of multiwall carbon nanotubes. If you know the composition, for example SrTiO3, it might be multiwalled SrTiO3. 

That's very interesting, but the danger is great that this is an artifact, especially since the TEM results do not correlate with your XRD measurements. Just as in the paper quoted from you would have to look in more detail here with high resolution analytical methods.

It can also be contaminants from the manufacturing process or by another test in your laboratory. Something I have several times seen.  :-(

But maybe you're really made new NT, then congratulations. :-/

It's interesting. Interplanar distance calculated from the inset is about 0.35 nm, which seems  to match with that of (020) of the monoclinic structure. But you'd better to conduct further characterizations, especially the composition. If the composition analysis confirms that it is indeed SrSiO3, congratulations, you probably made an interesting discovery. 

Dear All

Thanks for the suggestions and comments.

Dear Prof. Zhou

Thanks for the your comments. What are other characterization which clearly confirms the multiwalled nature of these particles? 

I have found another paper (file attached) from Scientific reports (Fig. 4d) which report similar type of loop as SiC graphene formation. Plz advice further.

Dear Prof. Volker

Thanks for the expert advice. Since, this type of multilayers is reported for Si based system, and i found number of particles showing closed loop structures. So, probably something mutiwalled or graphene may have formed. Plz advice further.

Dear Prof. Zhang

Thanks for encouraging comments. As per your advice I shall perform EDAX on these particles for composition analysis. Also, I have not studied TEM previously, so your advice will help me to find the phenomena behind this system. Plz advice further.

First of all, before any discussion, you have to be sure that this image is reproducible...