Effect of Boron Nitride on the Mechanical and Electrochemical Properties of Cement Composite

Abstract

Hexagonal boron nitride (h-BN) is well known for its unique properties, such as high thermal conductivity, excellent mechanical strength, high electrical insulating, and high chemical stability. This paper studies the effect of h-BN to the mechanical and electrochemical properties of cement concrete. Sodium cholate is used as an ionic surfactant to exfoliate h-BN and subsequently stabilize them in water solution. Different cement concrete samples with different doping levels of h-BN and different sizes of h-BN were prepared for comparisons. Also, steel fiber reinforced h-BN/cement concrete samples were also prepared. The results show that the addition of h-BN can improve the strength of cement composites, and the degree of reinforcement are influenced by the doping levels and feature size of h-BN. The corrosion resistance of h-BN/cement composites were also tested. Experiments results show that h-BN can enhance the corrosion resistance of cement composites.

Review of Boron Nitride Nanosheet-Based Composites for Construction Applications

“…They found that the specimen with 0.5 wt % BNNS had the highest flexural and compressive strengths . In another study, based on the results of a compressive test on two series of samples containing 500 and 5000 nm BNNS with a loading of 0.5, 1, and 2 wt % BNNS, the highest compressive strengths were achieved with 1 wt % of BNNS …”

“…As an ionic surfactant, its facial polarity 113 is effective for stabilizing the BNNS dispersion. 28 To sum up, the mechanical methods are useful for exfoliating the nanosheets and turning the agglomerates into smaller particles. However, as soon as the mechanical energy is removed, there is no force to hinder the formation of agglomerations induced by van der Waals forces between the particles.…”

“…Another potential surfactant is SC. As an ionic surfactant, its facial polarity is effective for stabilizing the BNNS dispersion …”

“…For instance, Wang et al concluded, based on a mini slump test, that workability of cement paste reduces with the addition of BNNSs. In another study, He and Yu compared plain concrete, concrete containing BNNS, and concrete containing both BNNS and sodium cholate by measuring the average spread of each specimen. In contrast to the previous study, the samples including BNNS showed an increase in fluidity.…”

“…Boron nitride is an extraordinary structure that forms the backbone of a two-dimensional (2D) nanoparticle known as a boron nitride nanosheet (BNNS). It has been the focus of the spotlight due to its unique mechanical, electrical, and thermal properties, which make it a promising material for industrial applications such as sandwiched electronic devices with high cutoff frequency, ultralight aerogels and freestanding membranes (Figure a), and cementitious composites . BNNS has also been incorporated into polymeric nanocomposites, which can be three-dimensional (3D) printed and used to manufacture self-supporting constructs (Figure b) .…”