Formation of well-connected conducting paths with the relatively small amount of carbon nanotubes (CNTs) is an important factor to attain high-quality conductors possessing high transmittance. Here, we prepared electrospun nanowebs consisting of elastic nanofibers which have attractive interaction with CNTs, and used them as a template to assist the deposition of CNTs at desired locations. Self-assembly of CNTs is achieved by dipping nanowebs into the CNT ink. This leads to a percolated structure even at low concentrations of CNTs so that high conductive and transparent conductors can be made. Elastic nanofibers also help to preserve conducting paths of the CNTs under a large level of strains, while CNT thin films exhibit drastic reduction in conductivity since some of conducting pathways are broke down and low conductive region are increasing. To enhance the conductivity of those conductors, chemical doping was carried out, which can not only increase the carrier concentration in semiconducting CNTs but also decrease the tunneling barrier between CNTs. The doping process can lower the resistivity by an order of magnitude but do not harm its transparency. Furthermore, highly stable conductivity over repetitive stretching/releasing cycles can be attained with the use of pre-stretched substrate. We put uniaxially prestrained electrospun nanowebs into CNT ink and release them, which results in a noodle-like buckled structure. These twisted and prestrained elastic nanofibers prevent breaking of CNT networks while stretching, so these new composites show reversible behavior in conductance.
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