Synergistic Enhancement on Mechanical Properties and Electrical Conductivity of Cementitious Materials through Novel Carbon Fiber–Graphene Integration

Conductive cement-based composites hold a vast potential for application, yet face considerable obstacles in optimizing their performance. Generally, improving the electrical conductivity of conductive cement-based composites frequently results in a compromise of their mechanical strength, and vice versa. In this study, we propose a novel design of carbon fiber–graphene composites by integrating a tiny amount of graphene on the surface of carbon fibers, aiming to efficiently exert the enhancement effect of graphene and carbon fibers on the electrical conductivity and mechanical properties of cement-based materials. This design method not only accomplishes efficient utilization of conductivity-enhanced phase (e.g., graphene) but also markedly enhances the interfacial bonding between carbon fibers and the cementitious matrix. Therefore, the electrical conductivity and mechanical properties of cement-based composites are synergistically enhanced. As a result, the electrical conductivity of the cementitious materials experiences a significant increase by an order of magnitude. Concurrently, there is an enhancement in flexural strength by 17% and in compressive strength by 35%, respectively. This work provides new insights into designing cost-effective, high-performance conductive cement-based composites.