Synthesis of composite of graphene and UO3 composite via one-step solution chemical reaction and its application to UO2-based accident tolerant fuel

In this paper, two kinds of composites constructed by UO3 nanoflakes (which is UO3 center dot yNH(3)center dot xH(2)O, precisely) and different graphene oxide (GO) nanosheets (homemade GO, GO-h, and commercial GO, GO-c) were prepared via solution chemical reaction. The two kinds of GO share similar morphology and possess the same species of functional groups. Nevertheless, GO-h possesses higher oxidization degree and thus could adsorb more uranyl ions, and the corresponding composite shows a much more regular shape: UO3 nanoflakes and GO nanosheets cross each other, which would help overcome the disadvantage of graphene aggregation. As a result, homemade reduced graphene oxide (RGO-h) sheets inside the final UO2 pellets (named as UO2/GO-h) could construct a well-bulit thermally conductive network to enhance its thermal conductivity. However, similar RGO-c network cannot be observed in the UO2/GO-c pellest originated from GO-c. Therefore, only the thermal conductivity of UO2/GO-h pellet acquires a dramatic increase, 37.30% relative to UO2 pellet at 1200 degrees C, showing that UO2/GO-h possesses great potential for the development of novel UO2-based ATF fuels.