Boosting the Power Output of a Cement-Based Triboelectric Nanogenerator by Enhancing Dielectric Polarization with Highly Dispersed Carbon Black Nanoparticles toward Large-Scale Energy Harvesting from Human Footsteps

A strategy to enhance the energy conversion performance of a cement-based triboelectric nanogenerator(TENG) has been proposed for large-scale energy harvestingfrom human footsteps. A cement-carbon black (CB) composite isfabricated by incorporating CB nanoparticles with a hydroxyethylcellulose (HEC) admixture and used as a triboelectric material forTENG. The fabricated cement-CB@HEC TENG exhibits a 13-fold enhancement of the electrical output with the highest powerdensity of 2.38 W/m2. The tremendous improvement is ascribedto a good dispersion of conductive CB nanoparticles in the cementmatrix, which is key for achieving a high dielectric constant that isrequired to intensify the triboelectric charge density of TENG.Moreover, it was found that the addition of the HEC admixtureplays a crucial role in not only providing a good dispersion of CB for generating dielectric polarization but also facilitating thedevelopment of a microstructure and crystallization of cement hydration products to reduce the formation of air voids andmicropores. These factors synergistically contribute to the improved dielectric constant and compressive strength of the cement-CB@HEC composite. This remarkable strategy presents great prospects for the development of smart cement materials for realizing applications in large-scale energy harvesting toward sustainable, clean, and renewable energy sources