Compared to a pristine NC film, the films reduced in Li + or Na + electrolytes show a much more significant change in the W 4f photoemission spectra, with much greater intensity at lower binding energy. Tungsten 4f photoemission spectra consist of spin-orbit doublets with an energy splitting of 2.1-2.2 eV. These parameters were used to fit the photoemission The interpretation of multi-peak structures in the photoemission spectra of metal oxides is actively debated. The first interpretation is that each component represents localized valence states, with a distribution of different states throughout the tungsten oxide octahedral network. The second interpretation is that the multiple components are derived from final-state effects due to interactions of the core-holes generated during photoemission with the valence electrons. Both interpretations have merit and reliable methods of differentiating between these two effects are not well established. Based on the photoemission spectra, there are two possible interpretations to the differences in the electronic state of tungsten in each sample and how it relates to the mechanisms for electrochromism.