Fig. 3From: One-pot synthesis of monodisperse CoFe2O4@Ag core-shell nanoparticles and their characterizationXPS spectra of CoFe2O4@Ag by argon ion etching before (a–d) and after (e–h). a, e C 1 s. b, f Co 2p. c, g Fe 2p. d, h Ag 3dBack to article page