Study on the regulation mechanism of hydration behavior, durability and electrochemical performance of Portland cement via nanocellulose-MXene synergistic modification

Cement-based materials face a fundamental contradiction, where achieving good structural load-bearing capacity, excellent conductivity, and long-term corrosion resistance remains challenging. However, how to introduce stable conductive phases and simultaneously improve strength without sacrificing durability remains a key scientific problem in functional concrete. To address this challenge, this study proposes a synergistic modification strategy using cellulose nanofibers (CNF) and MXene, systematically evaluating the multiscale effects of different dosages on hydration kinetics, pore structure, and electrochemical properties. The results show that only within a narrow range of CNF ≈ 20 mL and MXene ≈ 12 mL, the material can self-assemble a "high-speed electron channel – slow ion channel – interface passivation" triple barrier. MXene conductive nanosheets construct high-speed electron channels that lower the resistivity, while CNF regulates the formation of dense C-S-H gel networks that act as slow ion channels to retard corrosion ion diffusion. The synergistic modification also produces an enhanced interfacial protective effect, which may be associated with interactions among the surface functional groups of MXene/CNF and Ca²⁺ in the cementitious matrix. This synergistic mechanism contributes to a more favorable balance between electrical conductivity and corrosion resistance through coordinated regulation of electronic transport, ionic transport, and pore structure. This study provides a replicable nanostructure paradigm for marine concrete, 3D printing, and smart infrastructure, laying the foundation for the molecular-level design of green multifunctional concrete.