The growth of in-situ CNTs on slag to enhance electromagnetic interference shielding effectiveness of cement-based composite

The present work focused on growth of in-situ CNTs on slag through polymer pyrolysis chemical vapor deposition method (PP-CVD) for improving the electromagnetic interference shielding effectiveness of cement-based composite. The results indicated that numbers of in-situ CNTs were uniformly anchored on the slag particles after PP-CVD treatment, the density and aspect ratio of in-situ CNTs were increased, as the mass ratio of melamine to nickel acetylacetonate increased. However, when the mass ratios exceeded the critical value, amorphous carbons, in contrast to CNTs, were generated on slag particles. The EMI shielding effectiveness (SE) results showed that the EMI SEtotal of the in-situ CNT/slag cement-based composite reach up to 55 dB, much higher than that of the composite with addition of CNTs/slag powder (which were prepared by a combination of surfactant and ultrasonic methods with commercial CNTs), due to the higher electrical conductivity of the former resulted from the improved dispersion of CNTs within the cement-based composite. •In-situ CNTs/slag were prepared through polymer pyrolysis chemical vapor deposition method for improving the electromagnetic interference shielding effectiveness of cement-based composites.•The CNTs incorporated into the cement-based composite through in-situ CNTs/slag had excellent dispersion, resulting in an increase of 31.8% in electrical conductivity of cement-based composite.•An EMI SE of 55 dB was achieved for in-situ CNTs/slag modified cement-based composite.