Preparation and Mechanical Properties of Graphene Oxide: Cement Nanocomposites

Fakhim Babak,Hassani Abolfazl,Ghodousi Parviz,Rashidi Alimorad

doi:10.1155/2014/276323

Abstract

We investigate the performance of graphene oxide (GO) in improving mechanical properties of cement composites. A polycarboxylate superplasticizer was used to improve the dispersion of GO flakes in the cement. The mechanical strength of graphene-cement nanocomposites containing 0.1–2 wt% GO and 0.5 wt% superplasticizer was measured and compared with that of cement prepared without GO. We found that the tensile strength of the cement mortar increased with GO content, reaching 1.5%, a 48% increase in tensile strength. Ultra high-resolution field emission scanning electron microscopy (FE-SEM) used to observe the fracture surface of samples containing 1.5 wt% GO indicated that the nano-GO flakes were well dispersed in the matrix, and no aggregates were observed. FE-SEM observation also revealed good bonding between the GO surfaces and the surrounding cement matrix. In addition, XRD diffraction data showed growth of the calcium silicate hydrates (C-S-H) gels in GO cement mortar compared with the normal cement mortar.

Highlights

Cementitious materials are the most common construction materials used worldwide
The tensile strength of the specimens was observed to increase with nano-graphene oxide (GO) percentage until it reached 1.5%, after which a decrease in tensile strength was observed for 2 wt% GO content
As shown in this figure, specimens containing 1.5 wt% GO flakes exhibited about a 48% increase in tensile strength compared with that of the control mortar samples

Summary

Introduction

Cementitious materials (especially concrete) are the most common construction materials used worldwide. If nanoscale cracks can be successfully controlled, their propagation to the microlevel would be prevented Carbon nanostructures such as carbon nanotubes (CNTs, both single and multiwalled), carbon nanofibers (CNFs), and graphene have attracted attention from many concrete researchers because of their exceptional mechanical, chemical, thermal, and electrical properties, and good performance as polymeric reinforcement materials [3, 4]. Shah et al successfully dispersed 0.02 to 0.33 wt% untreated MWCNTs in water containing surfactants by applying optimum ultrasonication and before mixing with cement in water/cement ratios of 0.3 and 0.5 They reported improved mechanical (15 to 55% increase in Young’s modulus, 8 to 40% increase in flexural strength) and durability (30 to 40% reduction in autogenous shrinkage) properties [17]. In this paper, the effect of another emerging carbon nanostructure, graphene, on the mechanical properties of cement mortar is investigated

Experimental Procedures

Results and Discussion

Conclusions