In-situ growth of carbon nanotubes on ZnO to enhance thermoelectric and mechanical properties

Abstract As a high-temperature thermoelectric (TE) material, ZnO offers advantages of non-toxicity, chemical stability, and oxidation resistance, shows considerable promise as true ready-to-use module under air conditions. However, poor electrical conductivity high thermal severely hinder its application. Carbon nanotubes (CNTs) are often used reinforcing phase in composites, but it is difficult to achieve uniform dispersion CNTs due van der Waals forces. Herein, we developed an effective in-situ growth strategy homogeneous on nanoparticles by exploiting the vapor deposition (CVD) technology, order improve their mechanical properties, well reducing conductivity. Meanwhile, magnetic nickel (Ni) introduced catalysts for promoting formation CNTs, which can also enhance transportation matrices. Notably, significantly boosted from 26 79 S·cm −1 dense conductive CNT networks. The lattice ( κ L ) obviously declined intensification phonon scattering, resulting abundant grain boundaries interfaces ZnO-CNT composites. Importantly, maximum dimensionless figure merit zT 0.04 at 800 K obtained 2.0% Ni-CNTs/ZnO, three times larger than that CNTs/ZnO prepared traditional ultrasonic method. In addition, properties composites including Vickers hardness HV fracture toughness IC reinforced. This work provides valuable reference dispersing nano-phases TE materials both properties.