Fig. 6

High-resolution scanning XPS spectra detailed line scans of the pristine MIL-88B (left column), Co/Fe@C (middle column) and the post-catalysis form (after catalysis with H₂O₂): (a) survey spectra of elements; (b) C 1s; (c) O 1s; (d) Fe 2p; (e) Co 2p; (f) element contents