Because NaBiO3·XH2O is the comercia

Because NaBiO3·XH2O is the comercially available form employed by the nuclear energy and photocatalysis communities, an evaluation of its structure is important to understand structure-function relationships. Additionally, since bismuthate rapidly becomes amorphous in itsphotocatalytic form and in extremely acidic environments of nuclear fuel reprocessing solutions, the structural evolution with acidification is likewise important. Herein, we examine the short range order of both NaBiO3·XH2O (X = 3)·and its evolution upon acid-treatment. Pair distribution function (PDF) analysis of X-ray total scattering yields structural information, while XPS, wet chemical analysis, and energydispersive X-ray spectroscopy (EDX) provide information about theelemental composition and the oxidation states, on both the surface and in the bulk. We document the oxidation efficacy as a function of structural changes of Bi5+/Bi3+ evolution, employing the Ce3+/Ce4+ redox couple as a surrogate for Am3+ oxidation [14]. From these data, we produce a structural model for the hydrated form of sodium bismuthate, and indicates how the local environment evolves as the material becomes X-ray amorphous. Additionally, by pre-acidifyingsodium bismuthate prior to performing the Ce3+/Ce4+oxidation studies, we delineate the effects of solution conditions and materials state on oxidation efficacy.