Synthesis and characterization of CeO2 modified graphene oxide with improved wettability

Abstract

In this paper, CeO2 nanoparticles coated graphene oxide (CeO2@GO) nanocomposites were synthesized by a modified hydrothermal method. The morphology and structure of CeO2@GO nanocomposites were characterized systematically. Moreover, the wettability behavior of GO before and after coating CeO2 nanoparticles was investigated. It was found that the CeO2 nanoparticles with an average diameter of ~10 nm were successfully loaded on the GO surface. TEM investigations showed that the CeO2 nanoparticles loaded on the GO surface were dominated by an octahedral shape, and the main exposed surfaces of CeO2 nanoparticles were {111} facets. This was because the closed-packed plane CeO2 {111} had the lowest surface energy. After loading CeO2 on the GO surface, the contact angle between Al drop and CeO2@GO substrate was reduced from 166° to 70° by calculation, attributing to that the CeO2 coating increased the surface free energy of GO. This work provides a feasible method to prepare the rare earth oxides coated GO nanocomposites and shows potential applications in the field of graphene reinforced aluminum matrix composites (AMCs).