同济大学Xu Wei团队研究了多聚炔链的表面合成与表征。相关论文发表在2024年1月22日出版的《国家科学评论》杂志上。

该文报道了在Au(111)表面上用有机金属多聚炔脱金属合成聚炔碳链的方法，发现最长的聚炔碳链由~60个炔单元(120个碳原子)组成。研究人员还用键分辨原子力显微镜明确地揭示了，碳链的三键和单键交替的多聚结构。

此外，在4.7 K的温度下，通过尖端诱导脱卤并在双层NaCl/Au(111)表面开环C₁₄Cl₁₀，研究人员成功制备了原子精度聚炔C14, 并用扫描隧穿光谱测量了其带隙为5.8 eV，结果与理论HOMO-LUMO隙(5.48 eV)吻合较好。

据介绍，碳炔是一种稀有的sp杂化线性碳同素异形体，几十年来一直吸引着化学家和物理学家。由于碳炔具有较高的化学反应活性和极高的不稳定性，与sp2杂化碳同素异形体(如石墨烯)相比，人们对其的探索要少得多。

附：英文原文

Title: On-surface synthesis and characterization of polyynic carbon chains

Author: Gao, Wenze, Zheng, Wei, Sun, Luye, Kang, Faming, Zhou, Zheng, Xu, Wei

Issue&Volume: 2024-01-22

Abstract: Carbyne, an elusive sp-hybridized linear carbon allotrope, has fascinated chemists and physicists for decades. Due to its high chemical reactivity and extreme instability, carbyne was much less explored in contrast to the sp2-hybridized carbon allotropes such as graphene. Herein, we report the on-surface synthesis of polyynic carbon chains by demetallization of organometallic polyynes on the Au(111) surface, and the longest one observed consists of ～60 alkyne units (120 carbon atoms). The polyynic structure of carbon chains with alternating triple and single bonds was unambiguously revealed by bond-resolved atomic force microscopy. Moreover, an atomically precise polyyne, C14, was successfully produced via tip-induced dehalogenation and ring-opening of the decachloroanthracene molecule (C14Cl10) on a bilayer NaCl/Au(111) surface at 4.7 K, and a band gap of 5.8eV was measured by scanning tunnelling spectroscopy, in a good agreement with the theoretical HOMO–LUMO gap (5.48 eV).

DOI: 10.1093/nsr/nwae031

Source: https://dx.doi.org/10.1093/nsr/nwae031