The Journal of Physical Chemistry Letters has published an article about a study in which operando soft X-ray absorption spectroscopy (SXAS) is used to explore the electronic structure of Co3O4 under oxygen evolution reaction (OER).
The findings of the research reveal that “Co(Oh) in D-Co3O4 can be rapidly converted to active low-spin Co4+ under operando conditions, which cannot be observed by ex situ XAS (X-ray absorption spectroscopy)”.
Soft X-ray absorption spectroscopy experiments were conducted at the TLS BL-11A beamline in TFY mode at the National Synchrotron Radiation Research Center in Taiwan and Silson’s coated silicon nitride membranes were used (100 nm thick silicon nitride with an area of 1 × 1 mm^2, coated by 3 nm Ti/10 nm Au)
Here is the link to read the full paper!