Fig. 5: XPS spectra of the [BMIM][CO₂CH₃] electrolyte and working electrode after test.

a Ag3d high resolution XPS spectra for the electrode before (upper panel) and after (lower panel) the electrochemical test. b N1s high resolution XPS spectra of the pure [BMIM][CO₂CH₃] IL (upper panel) and the tested electrode (lower panel).