Electronic structure of b-VOPO4
نویسندگان
چکیده
Vanadium phosphorus oxides are used as catalysts in the selective oxidation of n-butane to maleic anhydride. The working catalyst comprises besides the main pyrophosphate phase in which the vanadium is in a 4+ oxidation state also a, predominantly preparation dependent, amount of different pentavalent vanadylorthophosphate phases. In order to elucidate the role of the pentavalent phases it is necessary to investigate them in detail. The present work reports the synthesis, characterization and a detailed investigation of the electronic structure of bulk b-VOPO4 in company with simulated and experimental core-shell excitation spectra.
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