Answer:
In explanation :P
Step-by-step explanation:
Cu was detected in CuS with X-ray absorption spectroscopy in the high-energy-resolution fluorescence detection (HERFD) mode. The S L2,3 emission spectrum of CuS was found to be significantly broader than Cu2S due to contributions from inequivalent S sites. This difference in the spectral width was used to distinguish between sulfide species formed on the Cu foil exposed to Na2S solutions
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