Incorporation of graphene oxide in MgO-SiO2 binder systems

The widespread application of MgO-SiO 2 binders is hindered by slow reaction kinetics and limited mechanical performance. Accordingly, this study investigated the influence of graphene oxide (GO) on MgO-SiO 2 binder hydration using isothermal calorimetry, XRD, FTIR, TG/DTG, and SEM at 1, 7, and 28 days. Results revealed time-dependent mechanisms: GO initially promotes brucite formation through water retention and nucleation; subsequently facilitates brucite dissolution enabling Mg 2 + participation in M-S-H formation; and ultimately provides interfacial area for M-S-H network development. Optimal concentration of 0.04 wt% achieved 65 MPa compressive strength (71% improvement), while higher concentration (0.08–0.12 wt%) showed reduced effectiveness due to agglomeration. This work provides mechanistic insights into GO’s stage-dependent roles, offering guidance for developing enhanced MgO-SiO 2 binder composites.