If you have a noble metal@oxide (core@shell) system where the noble metal exhibits surface plasmon ressonance UV-vis absorption band (Au, Ag or Cu) is it possible by UV-vis to know the formation of a core@shell NP.
Please give us more details of yous system so that we can give tips about it.
Actually I am trying to get semiconductor QDs shell @ rare earth nanoparticle core. I don't have very frequent access to SEM or TEM. So I wanted to know if there is any possibilities using other characterization techniques.
Recently we have published a work that describes how the Eu3+ emission spectra can be used to probe SnO2 particle size. In this case we used the difference in the emission of the Eu ions located in the surface and in the bulk of the SnO2 NPs.
Crystalline SnO2 Nanoparticles Size Probed by Eu3+ Luminescence
Mathias Strauss, Thalita A. Destefani, Fernando A. Sigoli, and Italo O. Mazali
Probably the same approach can be used to define if you are getting a core@shell system or not. But it depends on the dopant and host characteristic. Reading this article maybe will help you in opening your mind for new ideas and on giving you some insights.
Another issue that you may use at the PL analysis is the emission life time of your rare earth that may be different if you have a core@shell system. But I suggest looking into the literature for getting additional information in this case.
From scanning transmission electron microscopy (Cs-Corrected STEM), we can apply several technique such as EDS, EELS, HAADF-STEM and others and confirm the particles are core-shell, alloy or hetero structure.