EELS measurements were carried out using an aberration corrected ThermoFischer Scientific -Titan Cubed electron microscope, operating at 300 kV, equipped with an energy monochromator excited to a value of 0.7. The energy resolution provided by the electron monochromator, as measured from the full-width half maximum of acquired zero-loss peaks, was 100 meV. The dispersion of the spectrometer was set to 0.002 eVch -1 to visualize the plasmon edges. To analyze the EELS data sets, EELSModel software was used.