Effect of temperature on interface debonding behavior of graphene/graphene-oxide on cement-based composites

Temperature effect easily affect the adhesion of graphene/graphene oxide (GO) on the cement-based composites originating from the weaker non-covalent bonding at the interface, leading to weakening of the cementitious composite properties. In this study, the interfacial debonding behavior of graphene/GO and cement-based composites was investigated for low to high temperatures (250∼550K) using controlled molecular dynamics simulations. The maximum tensile force and work of adhesion both decrease with increasing temperature, and the value of GO is 5∼6 times that of graphene. Especially at the high temperature end, GO is still difficult to peel off (Fmax: 7.93×103 pN, Wmax:2129.60 Kcal/mol). Meanwhile, the insights into the distribution and concentration of functional groups have shown that high concentrations and edge functional groups can improve interface adhesion. Energy decomposition demonstrated that, compared to the Coulomb effect of charge and the prestress of surface wrinkles, the van der Waals effect plays a major role in interface adhesion. Entropy analysis further reveals the high temperature sensitivity of graphene and the low sensitivity of GO due to edge functional groups. We believe that the insight into the temperature effect of interface debonding behavior at nanoscale can provide theoretical support for the effective temperature working conditions of graphene/graphene-oxide on cement-based composites.