Effect of High-Dispersible Graphene on the Strength and Durability of Cement Mortars

Xiaoqiang Qi,Sulei Zhang,Tengteng Wang,Siyao Guo,Rui Ren

doi:10.3390/ma14040915

Abstract

Graphene’s outstanding properties make it a potential material for reinforced cementitious composites. However, its shortcomings, such as easy agglomeration and poor dispersion, severely restrict its application in cementitious materials. In this paper, a highly dispersible graphene (TiO2-RGO) with better dispersibility compared with graphene oxide (GO) is obtained through improvement of the graphene preparation method. In this study, both GO and TiO2-RGO can improve the pore size distribution of cement mortars. According to the results of the mercury intrusion porosity (MIP) test, the porosity of cement mortar mixed with GO and TiO2-RGO was reduced by 26% and 40%, respectively, relative to ordinary cement mortar specimens. However, the TiO2-RGO cement mortars showed better pore size distribution and porosity than GO cement mortars. Comparative tests on the strength and durability of ordinary cement mortars, GO cement mortars, and TiO2-RGO cement mortars were conducted, and it was found that with the same amount of TiO2-RGO and GO, the TiO2-RGO cement mortars have nearly twice the strength of GO cement mortars. In addition, it has far higher durability, such as impermeability and chloride ion penetration resistance, than GO cement mortars. These results indicate that TiO2-RGO prepared by titanium dioxide (TiO2) intercalation can better improve the strength and durability performance of cement mortars compared to GO.

Highlights

The development of cement as the most basic material in civil engineering was more than 100 years, and today, it remains the most commonly used construction material [1,2].With the increasing popularity of super high-rise, large span, and specially shaped buildings, the requirements for cement performance and durability are increasing
Mercury intrusion porosimetry (MIP) (Quantachrome, Boynton Beach, FL, USA) was used to probe the pore structure parameters, and the test can be used to investigate the effect of TiO2 -RGO and graphene oxide (GO) on the pore structure of cement mortars due to the wide range of measurements it produces
It is the same location of the UV-vis characteristic absorption peak that has been reported for GO [36]

Summary

Introduction

The development of cement as the most basic material in civil engineering was more than 100 years, and today, it remains the most commonly used construction material [1,2].With the increasing popularity of super high-rise, large span (sea-crossing bridges), and specially shaped buildings, the requirements for cement performance and durability are increasing. The performance of cement has been improved by many efforts such as adjusting the cement mortars ratio, optimizing the aggregate gradation, and adding reinforcements [4,5,6,7]. These do not change the structure of cement hydration products, and the problems of high brittleness and cracking of the cement mortars still exist. Due to its excellent properties, graphene, a novel nanomaterial, shows important promise in many fields such as electronics, photonics, biophysics, and materials science [14,15,16,17,18], and it has great potential for application in cement composites [19,20]

Methods

Results

Conclusion