Rybkovskiy D V, Koroteev V O, Impellizzeri A, Vorfolomeeva A A, Gerasimov E Yu, Okotrub A V, Chuvilin A, Bulusheva L G, Ewels C P
Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30, Building 1, 121205 Moscow, Russia.
Prokhorov General Physics Institute of the Russian Academy of Sciences, Vavilov Street 38, 119991 Moscow, Russia.
ACS Nano. 2022 Apr 26;16(4):6002-6012. doi: 10.1021/acsnano.1c11349. Epub 2022 Apr 4.
We identify the "missing" 1D-phosphorus allotrope, red phosphorus chains, formed in the interior of tip-opened single-walled carbon nanotubes (SWCNTs). Via a comprehensive experimental and theoretical study we show that in intermediate diameter cavities (1.6-2.9 nm), phosphorus vapor condenses into linear P8]P2 chains and fibrous red-phosphorus type cross-linked double-chains. Thermogravimetric and X-ray photoelectron spectroscopy analysis estimates ∼7 atom % of elemental phosphorus in the sample, while high-resolution energy dispersive X-ray spectroscopy mapping reveals that phosphorus fills the SWCNTs. High-resolution transmission electron microscopy (HRTEM) shows long chains inside the nanotubes with varying arrangement and packing density. A detailed match is obtained between density functional theory (DFT) simulations, HRTEM, and low-frequency Raman spectroscopy. Notably, a signature spectroscopic signal for phosphorus chain cross-linking is identified. When coupled with reinterpretation of literature data and wide-ranging DFT calculations, these results reveal a comprehensive picture of the diameter dependence of confined 1D-phosphorus allotropes.
我们识别出了在顶端开口的单壁碳纳米管（SWCNT）内部形成的“缺失”的一维磷同素异形体——红磷链。通过全面的实验和理论研究，我们表明，在中等直径的腔体（1.6 - 2.9纳米）中，磷蒸汽会凝结成线性P8]P2链以及纤维状红磷型交联双链。热重分析和X射线光电子能谱分析估计样品中元素磷的含量约为7原子%，而高分辨率能量色散X射线光谱映射显示磷填充了SWCNT。高分辨率透射电子显微镜（HRTEM）显示纳米管内部有排列和堆积密度各异的长链。在密度泛函理论（DFT）模拟、HRTEM和低频拉曼光谱之间获得了详细的匹配。值得注意的是，识别出了磷链交联的特征光谱信号。当结合对文献数据的重新解读和广泛的DFT计算时，这些结果揭示了受限一维磷同素异形体直径依赖性的全貌。
