A novel strategy utilizing graphene oxide/functionalized carbon nanotube/nanosilica sheet for nanomaterial incorporation in cement paste

This study addresses the limitations of conventional methods in incorporating nanomaterials, including prolonged dispersion times and handling challenges in construction field applications, by developing graphene oxide/functionalized carbon nanotube/nanosilica (GCS) sheets. The GCS sheet, as a portable sheet form of a nanomaterial composite, achieves high nanomaterial dispersibility with only 1 min of sonication. The dispersion efficiency of the GCS sheets was evaluated using UV–vis spectroscopy, zeta potential measurements, and transmission electron microscopy, and the impact on material properties was assessed using compressive strength tests. The hydration processes were investigated using X-ray diffraction and ²⁹Si nuclear magnetic resonance, and the nanomaterial dispersion within the cement matrix was studied using synchrotron X-ray nanoimaging. The GCS sheet facilitated more effective nanosilica dispersion on the graphene oxide plane compared to the powder form, achieving optimal dispersion in 1 min. This resulted in enhanced compressive strength, increased polymerization of calcium silicate hydrates, and a more elongated pore structure owing to the reduced aggregation of the GCS composites.