Transition of electrical conductivity in carbon nanotube/silver particle composite buckypapers

Abstract The electrical conductivity of carbon nanotube buckypapers can be dramatically increased by incorporation of silver particles contained in a commercial silver paste. Two methods, co-dispersion during the production of buckypaper and surface coating on a preformed buckypaper, were used to prepare composite buckypapers. The two types of composite buckypapers exhibited very different electrical conductivity profiles. The composite buckypapers prepared by the surface coating method showed a distinct step transition in electrical conductivity at 3 vol% silver content, leading to a 15-fold improvement at 6% silver content. The composite buckypapers prepared by the co-dispersion method showed a gradual change in electrical conductivity with increasing silver particle content, resulting in a five-fold improvement at 12% silver content. Surface and sectional morphologies of the two types of composite buckypapers were examined and related to their electrical conductivity profiles.