Fig. 3: XPS measurements of MoO3-Fe2O3 redox catalysts.
XPS spectra for (a) Fe 2p, (b) Mo 3d of as-prepared redox catalysts. I, II, III, IV, and V are for FeAl, 1Mo15FeAl, 1Mo12FeAl, 1Mo9FeAl, and 1Mo6FeAl, respectively. The a.u. stands for arbitrary units.
