I don't test these materials with Raman but you should take acre because Raman is very sensitive to the size and spatial distribution of the nanomaterial analyzed. C pic and Cu pic in Raman are different but if your nano Cu are very small and disttibuted ramdomly you ll get a signal of amorphous Cu (confinment effect). To be sure to discrimante the signal of the two material, TEM (SAD and other images modes like Bright field and Lattice fringes modes) or XRD will be the best techniques.

Hi,

I guess you are trying SERS of CNT and Raman spectra of pure Cu is not possible under normal conditions.

In a usual experiment, the pure metal does not perform Raman spectra. Thus, the observed spectra are often the metal surface enhanced Raman spectrum. In fact, these spectrum is from the other material, not metal.

Yes, it is indeed the case, I didn't get any spectra for a high content of Cu nanoparticles. I was observing normal Raman spectra, not SERS.

Probably similarly to gold nanoparticles?

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