A short discussion on how to effectively use graphene oxide to reinforce cementitious composites

Graphene oxide (GO) with extraordinary properties has been regarded as a good candidate to reinforce cementitious composites. However, direct incorporation of GO as a nano-filler into cementitious composites not only hardly ensures the well dispersion of GO in cement matrix, but also greatly increases the cost of final cementitious products. In this study, three key points on how to effectively use GO to reinforce cementitious composites, including dispersion-effectiveness of GO in cement matrix, interaction effectiveness of GO with supplementary cementitious materials (SCMs) and cost-effectiveness of GO reinforced cementitious composites, will be comprehensively discussed. Firstly, the mechanism of polycarboxylate ether (PCE) superplasticizer on pre-stabilizing GO in alkaline cementitious solution (ACS) is summarized and how effective of PCE on enhancing the mechanical performance of GO reinforced cementitious composites is analyzed. Secondly, interaction between the silica fume (one of the popular SCMs) and GO in ACS is investigated and the corresponding effect of silica fume on the dispersion of GO in ACS is discussed. Finally, a novel way using GO as a coating material for fiber treatment, such as carbon fiber, polyvinyl alcohol fiber and polyethylene fiber, is proposed, and it reveals that the cost of GO used as a coating material is 11 times lower than that of GO used as a nano-filler to reinforce cementitious composites, but it achieves a similar reinforcement to cementitious composites by strengthening the interfacial bonding between the fiber and cement matrix. In conclusion, the research outcomes give an important summary and guidance on how to effectively use GO to reinforce cementitious composites. (C) 2018 Elsevier Ltd. All rights reserved.