Synergistic effect of zero-dimensional spherical carbon nanoparticles and one-dimensional carbon nanotubes on properties of cement-based ceramic matrix: microstructural perspectives and crystallization investigations

Abstract

In the present investigation, hybrid effect of spherical carbon nanoparticles and carbon nanotubes as zero- and one-dimensional entities, respectively (synthesized by novel CVD route), on properties of cement ceramic matrix was studied. Ceramic matrix composites were fabricated using different dosages (% by wt. of cement) of as-synthesized nanoadditive (labeled as rCNTs) and tested for their resistance to compression at increasing hydration curing times of 7, 14, and 28 days. Evolution of different inorganic crystalline phases in composites was examined using X-ray diffraction (XRD). Improvement in mechanical behavior of composites was explained on the basis of microstructural observations using field emission scanning electron microscopy (FE-SEM). Electrical behavior was evaluated using four-probe method and it was observed that addition of nanoadditive had a semiconducting influence on ceramic matrix composites. Thermal behavior of composites was investigated using thermogravimetric analysis (TGA) and compared with that of unreinforced counterpart. All the properties of rCNT composites were compared with carbon black (pCB) cement mortar nanocomposites. Obtained results indicated a maximum improvement of 13.5% in strength in case of 0.125% rCNT cement mortar composite. Electrical and thermal properties were improved with incorporation of rCNTs indicating significant potential for the practical application of low-cost novel rCNT in the preparation of cement-based materials of high strength and smart functionality.