We use cookies to enhance your experience. By continuing to browse this site you agree to our use of cookies. More info.
Writing in the journal Construction and Building Materials, a team of scientists from China, the USA, and the UK have proposed a novel approach to creating smart cement.
Study: Graphene coated sand for smart cement composites . Image Credit: Okaycm'Stocker/Shutterstock.com
Cementitious composites have been used for centuries in the civil engineering industry. Whilst adequate mechanical and physical properties such as durability are a central requirement of these materials, in recent years there has been increasing research interest in imbuing them with functional properties.
This has led to the field of smart cementitious composites. Amongst the various functionalities required by civil engineers, electrically conductive properties have several benefits, such as building health monitoring, electromagnetic shielding, and de-icing capabilities. Smart cementitious composites can improve the resilience, safety, and lifetime performance of structures. This decreases maintenance costs and improves the carbon footprint of new structures.
Several materials have been investigated for their use as electrically-conductive additives for smart cementitious composites. These include carbon black, carbon nanotubes, carbon fibers, and graphene. Direct incorporation into the cementitious matrix has been the commonly used approach in these studies.
Incorporating these materials directly into cementitious matrixes has the effect of decreasing electrical resistivity. Studies have reported improvements by several orders of magnitude, but there is a critical problem with this approach. These improvements come at the cost of the composite’s mechanical strength. Furthermore, processes are costly, energy-intensive, and time-consuming.
Achieving satisfactory electrical conductivity also requires large proportions of these materials. Direct admixing in these concentrations causes increased viscosity and reduced workability of the final mixture. This can impact properties such as durability and strength in final hardened composites. A new strategy is therefore needed to realize the potential of smart cementitious composites.
This study has proposed a new strategy which can potentially overcome the issues with conventional admixing processes. Achieving a low-cost method that maintains the mechanical and physical properties of cementitious materials and improves their electrical conductivity is a key concern in this field of materials science.
The novel approach developed in the paper involves using fine aggregates which are coated with conductive graphene-based materials. Firstly, a uniform coating of graphene oxide was applied to sand and then annealed at 300 oC. The annealing process reduced graphene oxide to reduced graphene oxide. Microwave treatments were then employed to further reduce the coating to graphene.
The wettability and conductivity of graphene, graphene oxide, and reduced graphene oxide were evaluated by the researchers. Results of this analysis informed the optimization of the process. Additionally, coating efficiency and the nanomaterial’s effects on the aggregate particles physical properties were assessed.
Mechanical strength, flowability, microstructure and water sorption of the prepared cementitious mortars were analyzed and assessed by the authors. Finally, the prepared composite mortar’s piezoresisivity and electrical resistivity were evaluated.
The results of the study demonstrated that the novel approach could produce cementitious composite mortars with adequate electrical properties without a negative effect on the mechanical and physical properties of the final product. Coating the sand particles rather than directly incorporating nanomaterials into the mortar provides significant benefits for producing smart cementitious composites.
The novel approach set forth in the study imbues the cementitious mortar with enhanced self-sensing abilities as well as reduced electrical resistivity. Additionally, slightly improved flowability was observed, which addresses issues with mortar viscosity faced by conventional preparation processes. Moreover, there was no notable reduction in water absorption or mechanical strength.
SEM analysis revealed an approximately 62% coverage of sand particle surfaces by graphene. The average thickness of the coating was around 8.8%. Compressive testing also confirmed that the coating developed in the study gives the mortar dependable piezoelectric responses to compressive loading.
The nano-coating approach does not rely on binder chemistry. This means that it can be implemented universally, across different cementitious composites with conventional or non-conventional binder materials.
In summary, the study has demonstrated an approach which improves upon conventional methods of preparing smart cementitious composites. A simple and efficient process, the author’s method can be easily applied to industrial scale operations, which has significant benefits for the construction and civil engineering industries.
The authors have presented a promising strategy for improving cementitious mortars and imparting advanced functionalities such as electrical conductivity and self-sensing abilities. However, some challenges still need to be overcome before this process can be considered for commercial applications. Further research on optimizing coating efficiency and quality needs to be performed in future studies.
More from AZoM: What is Glow Discharge Optical Emission Spectrometry?
Lu, D et al. (2022) Graphene coated sand for smart cement composites Construction and Building Materials 346(5) 128313 [online] sciencedirect.com. Available at: https://doi.org/10.1016/j.conbuildmat.2022.128313
Disclaimer: The views expressed here are those of the author expressed in their private capacity and do not necessarily represent the views of AZoM.com Limited T/A AZoNetwork the owner and operator of this website. This disclaimer forms part of the Terms and conditions of use of this website.
Reg Davey is a freelance copywriter and editor based in Nottingham in the United Kingdom. Writing for News Medical represents the coming together of various interests and fields he has been interested and involved in over the years, including Microbiology, Biomedical Sciences, and Environmental Science.
Please use one of the following formats to cite this article in your essay, paper or report:
Davey, Reginald. (2022, July 20). Creating Smart Cement with Graphene-Coated Sand. AZoM. Retrieved on August 20, 2022 from https://www.azom.com/news.aspx?newsID=59594.
Davey, Reginald. "Creating Smart Cement with Graphene-Coated Sand". AZoM. 20 August 2022. <https://www.azom.com/news.aspx?newsID=59594>.
Davey, Reginald. "Creating Smart Cement with Graphene-Coated Sand". AZoM. https://www.azom.com/news.aspx?newsID=59594. (accessed August 20, 2022).
Davey, Reginald. 2022. Creating Smart Cement with Graphene-Coated Sand. AZoM, viewed 20 August 2022, https://www.azom.com/news.aspx?newsID=59594.
Do you have a review, update or anything you would like to add to this news story?
At the Advanced Materials Show 2022, AZoM caught up with the CEO of Cambridge Smart Plastics, Andrew Terentjev. In this interview, we discuss the company's novel technologies and how they could revolutionize how we think about plastics.
At the Advanced Materials Show in June 2022, AZoM spoke with Ben Melrose from International Syalons about the advanced materials market, Industry 4.0, and efforts to move toward net-zero.
At the Advanced Materials Show, AZoM spoke with Vig Sherrill from General Graphene about the future of graphene and how their novel production technique will lower costs to open up a whole new world of applications in the future.
This product profile describes the Flex Raman Catalog.
This is the full list of rotary evaporators offered by IKA Werke.
This product from Alicona features Cobots, which consist of a collaborative 6-axis robot and optical 3D measuring sensors to provide user-friendly measurement automation.
This article provides an end-of-life assessment of lithium-ion batteries, focusing on the recycling of an ever-growing amount of spent Li-Ion batteries in order to work toward a sustainable and circular approach to battery use and reuse.
Corrosion is the degradation of an alloy caused by its exposure to the environment. Corrosion deterioration of metallic alloys exposed to the atmosphere or other adverse conditions is prevented using a variety of techniques.
Due to the ever-increasing demand for energy, the demand for nuclear fuel has also increased, which has further created a significant increase in the requirement for post-irradiation examination (PIE) techniques.
AZoM.com - An AZoNetwork Site
Owned and operated by AZoNetwork, © 2000-2022