High performance inorganic fullerene cage WS₂ enhanced cement

An original cement based material enhanced with inorganic fullerene tungsten disulfide (IF-WS₂) nanoparticles has been engineered with superb shock absorbing properties. Physical properties were attributed to the IF-WS₂ nano-hollow multiple layered onion-like structure. The effect of IF-WS₂ concentration at 0.1 wt%, 1 wt% and 5 wt% on the hydration kinetics of ordinary Portland cement (CEM1), electrical impedance, thermal stability, rheology and strength development was thoroughly evaluated. X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and X-ray diffraction (XRD) studies confirmed the formation of the new phase, calcium tungstate (CaWO₄), at the nano-particle/cement matrix interface during early hydration. 1 wt% IF-WS₂ additions enhanced the impact energy of CEM1 by 89% compared to the control. An IF-WS₂ cementitious mixture was developed for 3D printing based on the 1% WS₂-CEM composition. The mix exhibited excellent workability and buildability enabling the creation of a layer-by-layer printed component. Intimate interlayer adhesion minimized the presence of voids leading to a high flexural strength of 6.7 MPa, which equated to an over 86% improvement compared to plain CEM1 printed components. This study showcases IF-WS₂ nanoparticles as a new ground-breaking additive enabling the production of high-performance cementitious construction materials, for use under extreme environments demanding high strength and impact resistance.