Reason for getting Fe2+ peak for BiFeO3 or Fe2O3 in XPS?

I don't understand while doing XPS I m getting Fe2+ peak for BiFeO3 and Fe2o3 samples. Fe is in +3 states in BiFeO3 and Fe2O3. So, why I m getting Fe2+ in that sample?

20 February 2023 1,807 4 View