Effect of graphene oxide on hydration activity of spherical magnesium oxide

The spherical morphology of magnesium oxide (MgO) exhibits a high porosity and an extensive specific surface area, contributing to its significant hydration activity. These characteristics make it a valuable material across various applications in the construction industry. Graphene oxide (GO) is rich in functional groups, which have been increasingly utilized in recent years for the surface modification of various materials. In this study, spherical magnesium oxide was synthesized, and GO was applied to its surface using a wet mixing method to investigate the effects of GO on the hydration performance of magnesium oxide and to analyse the underlying mechanisms. The results indicate that within the range of 0.0–0.6% GO content, the hydration activity of magnesium oxide first decreases and then increases with increasing GO dosage. GO tends to adsorb onto the magnesium oxide surface during hydration, initially inhibiting early hydration reactions. However, when the GO content exceeds 0.3%, free GO in the system complexes with Mg2 + ions in the solution, which subsequently promotes the hydration of magnesium oxide.