Increasing self-sensing capability of carbon nanotubes cement-based materials by simultaneous addition of Ni nanofibers with low content

This paper aims to increase self-sensing capability of carbon nanotubes cement-based materials by simultaneous addition of Ni nanofibers with low content. The carbon nanotubes cement-based composites with a low content of Ni nanofibers and without Ni nanofibers were fabricated. The microstructures of as-fabricated cement-based composites were observed with transmission electron microscopy (TEM), scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS). Besides, the conductivity and pressure sensitivity of as-fabricated cement-based composites were studied by four electrode voltammetry. The results show that the Ni nanofibers and carbon nanotubes were well dispersed in the as-fabricated cement-based composites. The resistivities of as-fabricated cement-based composites show typical percolation phenomenon with the increases of carbon nanotube contents. The addition of Ni nanofibers with a low content induces the increase in the conductivity of cement-based composites, but not change the percolation threshold of carbon nanotubes. Moreover, the addition of Ni nanofibers with a low content increases the sensitivity, linearity and repeatability of cement-based composite with carbon nanotubes. (C) 2020 Elsevier Ltd. All rights reserved.