Bandgap, band edge positions as well as the overall band structure of semiconductors are of crucial importance in
photoelectrochemical and photocatalytic applications. The energy position of the band edge level can be controlled by
the electronegativity of the dopants, the pH of the solution (flatband potential variation of 60 mV per pH unit), as well as
by quantum confinement effects. Accordingly, band edges and bandgap can be tailored to achieve specific electronic,
optical or photocatalytic properties. Synchrotron radiation with photon energy at or below 1 keV is giving new insight
into such areas as condensed matter physics and extreme ultraviolet optics technology. In the soft x-ray region, the
question tends to be, what are the electrons doing as they migrated between the atoms. In this paper, I will present a
number of soft x-ray spectroscopic study of nanostructured 3d metal compounds Fe2O3 and ZnO.
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