Nano Structural Materials Center, School of Materials Science and Engineering , Nanjing University of Science and Technology , Nanjing 210094 , China.
Department of Materials Science & Engineering , North Carolina State University , Raleigh , North Carolina 27695 , United States.
ACS Appl Mater Interfaces. 2018 Mar 7;10(9):8197-8204. doi: 10.1021/acsami.7b19012. Epub 2018 Feb 21.
Carbon nanotube (CNT) fiber has not shown its advantage as next-generation light-weight conductor due to the large contact resistance between CNTs, as reflected by its low conductivity and ampacity. Coating CNT fiber with a metal layer like Cu has become an effective solution to this problem. However, the weak CNT-Cu interfacial bonding significantly limits the mechanical and electrical performances. Here, we report that a strong CNT-Cu interface can be formed by introducing a Ni nanobuffer layer before depositing the Cu layer. The Ni nanobuffer layer remarkably promotes the load and heat transfer efficiencies between the CNT fiber and Cu layer and improves the quality of the deposited Cu layer. As a result, the new composite fiber with a 2 μm thick Cu layer can exhibit a superhigh effective strength >800 MPa, electrical conductivity >2 × 10 S/m, and ampacity >1 × 10 A/cm. The composite fiber can also sustain 10 000 times of bending and continuously work for 100 h at 90% ampacity.
碳纳米管（CNT）纤维由于 CNT 之间的接触电阻较大，其导电性和载流量较低，尚未显示出作为下一代轻质导体的优势。在 CNT 纤维上涂覆金属层如铜已成为解决此问题的有效方法。然而，CNT-Cu 界面的弱结合力极大地限制了其机械和电学性能。在这里，我们报告说，在沉积铜层之前引入 Ni 纳米缓冲层可以形成强的 CNT-Cu 界面。Ni 纳米缓冲层显著提高了 CNT 纤维和铜层之间的载荷和热传递效率，并改善了沉积铜层的质量。结果，具有 2 μm 厚 Cu 层的新型复合纤维表现出超高有效强度>800 MPa、电导率>2×10 S/m 和载流量>1×10 A/cm。该复合纤维还可以承受 10000 次弯曲，并在 90%载流量下连续工作 100 h。
