3 / 2017-11-30 20:00:03

Graphite nanoplatelets and graphene oxide influence on C-S-H formation. I.

Cement,Graphene,Graphene oxide,silica,dispersion,pozzolanic reaction,C-S-H

Graphene, graphite nanoplatelets and graphene oxide are emerging nanomaterials for future technologies. Despite the conservative nature of the building industry, nanomaterials are already making their way into some construction applications and nanotechnology seems to have the potential to be the key to open a new season in the field of the built environment.
Recent studies reported that graphene oxide increases toughness and strength of hardened cement-based mixtures. The interaction between the carbon nano-additives and C-S-H, the cement phase responsible of the mechanical properties, is not clear yet. In this paper, we investigate “if and how” graphite nanoplatelets and graphene oxide impact on the morphology and the kinetics of C-S-H formation, considering the simple reaction between calcium oxide and silica. The CaO/SiO2 ratio was kept equal to the stoichiometry of the C3S phase. Influence on hydration by two different types of silica having very different specific area was considered. Carbon nanomaterials were used at low concentration (<0.20% by weight). Instrumental analyses of the products were performed by Infrared and Raman spectroscopy, TG and SEM analysis up to four weeks. Results indicate that GO interacts with C-S-H phase and hinders its formation while GNPs remain only dispersed in the matrix.