Uranium tetrafluoride (UF4) powder analyzed by XPS

XPS was performed on as-received and Ar+-sputtered uranium tetrafluoride (UF4) powder. The as-received powder surface exhibits stoichiometric UF4 with hydrocarbon contamination and surface impurities of uranium dioxide (UO2) and uranyl fluoride (UO2F2). Sputtering removes a majority of surface contamination and impurities, while also partially reduces the powder surface to uranium trifluoride (UF3).