Molecular dynamics of C–S–H production in graphene oxide environment

Abstract

Abstract The process of calcium silicate hydrate (C–S–H) generation in graphene oxide (GO) nanoslits was investigated via molecular dynamics simulations using the structural polymerization reaction of silica chains in the synthesis of silica gels. The structural evolution of C–S–H, radial distribution functions, chemical components, and distribution of Q n units in the system were analyzed to investigate the influence of GO on the early growth mechanism of C–S–H and compare the structural differences of C–S–H in the presence and absence of GO. The results showed that the proportion of silicon atoms bonded to bridge-site oxygen atoms in the C–S–H structure increased in the presence of oxygen-containing graphene groups. Ion adsorption in the GO surface layer led to an increase in the degree of polymerization of C–S–H. The nucleation and templating effects of GO were confirmed, revealing the intrinsic mechanism for the formation of GO-modified reinforced cementitious materials.