Crystalline C 3 N 3 H 3 tube (3,0) nanothreads

作者：Dexiang Gao, Xingyu Tang, Jingqin Xu, Xin Yang, Peijie Zhang, Guangwei Che, Yajie Wang, Yongjin Chen, Xiang Gao, Xiao Dong, Haiyan Zheng, Kuo Li, Ho‐kwang Mao · 发表于：Proceedings of the National Academy of Sciences · 年份：2022 · DOI：10.1073/pnas.2201165119 · 被引用次数：39 · 研究领域：Diamond and Carbon-based Materials Research、High-pressure geophysics and materials、Force Microscopy Techniques and Applications

Carbon nanothread (CNTh) is a “one-dimensional diamond polymer” that combines high tensile strength and flexibility, but it severely suffers from intrathread disorder. Here, by modifying the reactivity and the stacking ordering of the aromatic precursor, crystalline C3N3H3 CNTh with perfect hexagonal orientation and stacking was synthesized at 10.2 GPa and 573 K from s-triazine. By Rietveld refinement of X-ray diffraction data, gas chromatography mass spectrometry investigation, and theoretical calculation, we found that synthesized CNTh has a tube (3,0) structure, with the repeating s-triazine residue connected solely by C–N bonds along the thread. A “peri-cage” reaction, the concerted bonding between six C and N atoms, instead of [4 + 2] or [1,4] addition reactions, was concluded for the formation of CNThs, and the critical bonding distance between the nearest intermolecular C and N was ∼2.9 Å. The formation of a “structure-specific” crystalline CNTh with C and N orderly distributed highlighted the importance of reaction selectivity and stacking order of reactant molecules, which have great significance for understanding the polymerization of aromatic molecules under high pressure and developing new crystalline CNThs.