Crystal growth of K 2UO 4 and Na 4UO 5 using hydroxide fluxes

Abstract

The crystal growth of two uranium-containing oxides, K 2UO 4 and Na 4UO 5, utilizing hydroxide melts is reported. Our group has been investigating the crystal growth of complex oxides with new compositions and structure types using molten hydroxide fluxes. In this paper we describe the application of this method to uranium oxides, where the dissolution of the uranium cations in hydroxide melts and subsequent re-crystallization leads to the formation of alkali metal–uranium oxides. This is the first report of the use of molten hydroxides as a medium for crystal growth of uranium-containing oxides.