Dispersion strategies development for high-performance carbon nanomaterials-reinforced cementitious composites − critical review on properties and future challenges

Carbon nanomaterials (CNMs) including carbon nanotubes (CNTs), graphene nanosheets (GNS), carbon nanofibers (CNFs), graphene oxide (GO), with their excellent physical and chemical properties, have drawn widespread attention in the cement industry. This review introduces the dispersion strategies of CNMs in cementitious composites fabrication procedures before providing a comprehensive summary of the corresponding principles, advantages, limitations, and critical considerations. We also reviewed the latest CNMs dispersion characterization techniques and the dispersion effectiveness evaluation methods. Furthermore, the properties of cementitious composites incorporating CNMs, including workability, mechanical strength, durability, electrical conductivity and thermal conductivity, are summarized. The impact of dispersion strategies on these properties is analyzed, and potential causes behind performance inconsistencies are discussed. This review found that the current research faces several challenges: the lack of standardized mix proportions and dispersion protocols hinders result comparison, and inconsistent characterization methods, insufficient cost/lifecycle analyses, combined with unclear links between CNMs’ properties and enhancement, collectively limit practicality. Therefore, future works should focus on establishing unified guidelines for production and characterization, conducting cost-sustainability assessments, and clarifying CNMs’ property-performance relations to advance engineering applications.