Enhancing the strength, toughness, and electrical conductivity of twist-spun carbon nanotube yarns by π bridging

The weak interfacial interactions between carbon nanotube (CNT) always results in low stress load transfer efficiency in CNT yarns, herein we fabricated strong, highly conducting CNT yarns at room temperature using molecules having aromatic end groups, π bridging neighboring CNTs. The resulting CNT yarns have high tensile strength with 1697 ± 24 MPa, toughness with 18.6 ± 1.6 MJ/m3, and electrical conductivity with 656.2 S/cm, which are 3.9, 2.5, and 3.5 times, respectively, as high as that of the neat CNT yarn. The specific tensile strength of the resulting CNT yarn is higher than that for previously reported CNT yarns fabricated at room temperature, even that for some CNT yarns fabricated using corossive environments or extreme temperature. This π bridging strategy provides a promising avenue for fabricating high performance CNT yarns under ambient conditions. The new concept demonstrated in this work is applying π bridging strategy for constructing strong and highly conductive carbon nanotube yarns via interfacial design of π–π conjugated interaction. The π bridging strategy is very feasible and without any harsh conditions, providing an insightful approach for constructing high performance CNT yarns in the future. [Display omitted]