Anisotropic thermal transport and interfacial binding mechanism in graphene Oxide/C-S-H composites: a molecular dynamics study

The thermal properties of calcium silicate hydrate (C-S-H) and its interaction with graphene oxide (GO) are explored using the molecular dynamics method. As the main hydration product of cement, understanding the intrinsic thermal transport of C-S-H is crucial for solving the heat dissipation problem of mass concrete. The three principal thermal conductivities of C-S-H along x-, y-, z- axis are estimated respectively. The results show that C-S-H exhibits anisotropic thermal characteristics, and the volumetric thermal conductivity is calculated to be 1.28 W/(mK). Furthermore, the interfacial binding energy between C-S-H and graphene/GO is investigated to evaluate the stability of the composite system. It is found that the binding energy increases with the oxidation degree of GO, and the xy-plane of C-S-H exhibits the strongest affinity. The results provide fundamental data for the thermal design of cement-based composites.