Synergetic Effects of Alternating Oxidant and Carbon Supply to Enhance Defect Healing of Single‐Walled Carbon Nanotubes

ABSTRACT The technological potential of carbon nanotubes (CNTs) is strongly limited by structural defects, which degrade their outstanding properties. Conventional strategies for post‐growth defect healing exhibit moderate efficiency and result in unfavorable structural alterations. Herein, we propose a two‐step ‐assisted multiple‐cycle strategy for the efficient and scalable healing of CNT defects while maintaining their structure. functions as an oxidizing agent with preferential reactivity toward defective sites such as adatoms and Stone‐Wales defects, enabling efficient etching while minimizing structural damage. In combination with , this method can substantially improve the crystallinity of CNTs, without inducing tube coalescence. The proposed approach was systematically applied to three types of single‐walled CNTs: lab‐grown CNTs, commercial eDIPS 2.0, and super‐growth CNTs. Raman spectroscopy, thermogravimetric analysis, and transmission electron microscopy confirmed the enhancement in crystallinity and thermal stability of CNTs without diameter changes, whereas isotope labeling with verified the improvements originated from defect healing rather than the growth of new CNTs. Notably, the proposed healing process improved the ratio of eDIPS 2.0 to 141, underscoring the effectiveness of this strategy. Overall, the proposed ‐assisted method shows high reproducibility, broad applicability, and superior structural preservation, establishing a scalable pathway for the post‐synthesis healing of CNTs.