Differentiation of tin oxides using electron energy-loss spectroscopy

We have used electron energy-loss spectroscopy to search for differences in the energy-loss near-edge structure of SnO, SnO2, and an intermediate oxide, with a view to distinguishing them unambigously. We have found that the oxygen K edge exhibits clear differences that can be used for fingerprinting each phase. The oxygen edge appears at the same position for each phase whereas a chemical shift of the Sn M-4,M-5 edge of about 3.5 eV was observed between phases with Sn in 2+ and 4+ oxidation states. Both observations can be used to distinguish between the three phases, allowing their on-line identification within nanostructured materials.