“…Figure S11 indicates that all five metal elements added were detected on the surface of the catalyst Fe 12 Ni 23 Cr 10 Co 30 Mn 25 /CNT, which is consistent with the mapping results, while three non-metallic elements (C, N, and O) were also detected, which were derived from the acid-treated CNT. The Fe 2p peak diagram (Figure b) indicates that the Fe in Fe 12 Ni 23 Cr 10 Co 30 Mn 25 /CNT exhibits three states, the metal state at 0 valency (707.4 and 720.5 eV) and the oxidation states at +2 (710.4 and 723.5 eV) and +3 (712.1 and 725.2 eV) valencies, respectively. ,− The Ni 2p peak diagram (Figure c) indicates that the Ni in Fe 12 Ni 23 Cr 10 Co 30 Mn 25 /CNT exhibits two states, the 0-valent metallic state (852.9 and 870.2 eV) and the +2 valent oxidation state (855.7 and 873.0 eV), respectively. , Fitting of the Cr 2p profile (Figure d) revealed the presence of both the 0-valent (573.9 and 586.2 eV) metallic state and the +3 valent (578.8 and 588.1 eV) oxidation state of Cr in Fe 12 Ni 23 Cr 10 Co 30 Mn 25 /CNT . The Co 2p peak spectrum (Figure e) indicates that Co exhibits two forms in Fe 12 Ni 23 Cr 10 Co 30 Mn 25 /CNT, the 0-valent (778.9 and 793.9 eV) metallic state and the +2 valent (781.9 and 797.6 eV) oxidation state. , The results of Mn 2p resolution indicate that Mn exhibits two morphologies in Fe 12 Ni 23 Cr 10 Co 30 Mn 25 /CNT, the 0-valent (636.5 and 647.7 eV) metallic state and the +2 valent (641.5 and 652.7 eV) oxidation state .…”