Abstract
Lightweight and highly conductive carbon nanotube fibers (CNTFs) are attractive for flexible electronics, yet their performance remains constrained by inefficient charge transport. Here we report a synergistic doping strategy that integrates in-plane nitrogen doping with endohedral molybdenum pentachloride (MoCl5) incorporation to produce CNTFs with exceptional electrical properties and environmental durability. Nitrogen doping creates sidewall defect sites that promote MoCl5 encapsulation, yielding a strong charge-transfer effect and markedly increased carrier density. The resulting fibers achieve a high specific electrical conductivity of 14166 S m2 kg−1 and a current carrying capacity of 1241 A mm−2, surpassing copper by 115% and 28%, respectively. The CNTFs also exhibit high flexibility and environmental stability, retaining performance under thermal, mechanical, and solvent stresses. When woven into textiles, they deliver an electromagnetic shielding effectiveness of 92.7 dB (8.2-12.4 GHz). This work establishes a scalable doping approach for fabricating ultrahigh-conductivity CNTFs for advanced flexible electronics.
Data availability
All data supporting the findings of this study are available within the paper and its Supplementary Information files. Source data are provided with this paper. Data are also available from the corresponding author upon request. Source data are provided with this paper.
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Acknowledgements
This work was supported by the National Key Research and Development Program (Grant Nos. 2022YFA1203302 and 2022YFA1203304 to J.Z.), the National Natural Science Foundation of China (Grant Nos. 52202032 to M.J., 52522202 to M.J., 52021006 to J.Z., and T2188101 to J.Z.), the Beijing National Laboratory for Molecular Sciences (Grant Nos. BNLMS202412 to M.J. and BNLMS-CXTD-202001 to J.Z.), the Beijing Natural Science Foundation (Grant No. 2222094 to M.J.), the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDB36030100 to J.Z.), and the Shenzhen Science and Technology Innovation Commission (Grant No. KQTD20221101115627004 to J.Z.). The authors thank Prof. Haobin Zhang from Beijing University of Chemical Technology for assistance with electromagnetic interference shielding effectiveness measurements.
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The manuscript was written through the contributions of all authors. J.Z. and M.J. conceived the idea and designed the project. T.S. carried out the preparation of samples and characterization. J.H., B.Y., Y.Z., X.H., Z.W., X.Z. (Zhang), X.L., X.Z. (Zhao), J.Y., L.K., and Y.S. provided the analysis and discussion of experimental and theoretical results. T.S., J.H., Y.S., M.J., and J.Z. prepared the manuscript. All authors discussed the results and commented on the manuscript.
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Sun, T., Huang, J., Yu, B. et al. Synergistic nitrogen and endohedral MoCl5 doping for ultrahigh-conductivity carbon nanotube fibers. Nat Commun (2026). https://doi.org/10.1038/s41467-026-69498-7
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DOI: https://doi.org/10.1038/s41467-026-69498-7
