Graphene nanoribbons: A novel additive for enhancing the fire resistance of cementitious composites

This study investigated the effectiveness of graphene nanoribbons (GNRs) as nanoadditives for enhancing fire resistance of cementitious composites and compared their performance with conventional carbon nanotubes (CNTs). First, GNRs with striped structures exhibited superior dispersion stability compared to CNTs. Second, GNRs demonstrated excellent thermal stability, remaining structurally intact at 800 °C, while CNTs began decomposing above 450 °C. At room temperature, the GNRs significantly promoted the hydration reaction of cement clinkers, reduced the porosity, and refined the pore structure, thereby enhancing the mechanical properties of the cementitious composites. In high-temperature environments, GNRs act as bridges for cracks, effectively mitigating the deterioration of the mechanical strength caused by the dehydration and decomposition of hydration products. Moreover, the GNRs inhibited pore development and elongation, improving fire resistance. Overall, this study highlights the potential of GNRs as promising nanomaterials for enhancing the performance of cementitious composites under high-temperature conditions.