Stress-free strong carbon bundles
Yunxiang Bai, Rufan Zhang, Xuan Ye, Zhenxing Zhu, Huanhuan Xie, Boyuan Shen, Dali Cai, Bofei Liu, Chenxi Zhang, Zhao Jia, Shenli Zhang, Xide Li, Fei Wei
Carbon nanotubes (CNTs) are renowned for their exceptional mechanical properties, and especially for being one of the strongest materials known to date. When assembled in bundles, however, their tensile strength drops significantly below that of single CNTs due to misalignment, defects and impurities. Now, Bai and co-workers have obtained centimetre-long CNT bundles fabricated via a synchronous tightening and relaxing strategy aimed to release the non-uniform initial strains of individual CNTs. The mechanical properties of this CNT-based material show a significant macroscale enhancement with respect to other reported strong fibres as evidenced by a record high tensile strength of 80 GPa. The artist’s impression on the cover image shows such an aligned and defect-free ultralong bundle consisting of many individual CNTs.