Figure 3: XAS characterization.
From: High-performance hybrid oxide catalyst of manganese and cobalt for low-pressure methanol synthesis

X-ray absorption spectra of (a) manganese L3 edge and (b) cobalt L3 edge comparing the fresh and spent MnOx/m-C3O4 catalysts. The changes in the profile of these spectra evidence the change in the oxidation state for both the Co and Mn. Arrows indicate relative changes in oxidation states.