美国伊利诺伊大学芝加哥分校Nan Jiang团队报道了有机硼酚垂直异质结构界面相互作用的埃尺度光谱可视化。相关研究成果发表在2021年8月9日出版的国际学术期刊《美国化学会杂志》。

由于硼-硼键的独特性质，二维硼单分子膜（即硼酚）有望用于各种能源、催化和纳米电子器件技术。为了实现其全部潜力，硼酚需要与其他材料无缝连接，从而需要基于硼酚的异质结构的原子尺度表征。

该文中，研究人员报道了硼酚与四苯基二苯并菲（DBP）的垂直积分结合，并用超高真空尖端增强拉曼光谱（UHV-TERS）测量了埃尺度的界面相互作用。除了识别吸附DBP的振动特征外，TERS还揭示了分子层下方硼吩晶格的细微波纹和压缩应变。借助于5个化学空间分辨率，诱导的界面应变在硼酚中扩展到分子区域以外约1nm。分子操纵实验证明了界面应变的分子起源，并允许原子控制局部应变，其大小可低至～0.6%。

除了首次实现有机/硼酚垂直异质结构外，该研究还表明，UHV-TERS是一种强大的分析工具，可在原子尺度上对掩埋和高度局部化界面特性进行光谱研究，同时可应用于其他类别的异质结材料。

附：英文原文

Title: Angstrom-Scale Spectroscopic Visualization of Interfacial Interactions in an Organic/Borophene Vertical Heterostructure

Author: Linfei Li, Jeremy F. Schultz, Sayantan Mahapatra, Xiaolong Liu, Chasen Shaw, Xu Zhang, Mark C. Hersam, Nan Jiang

Issue&Volume: August 9, 2021

Abstract: Two-dimensional boron monolayers (i.e., borophene) hold promise for a variety of energy, catalytic, and nanoelectronic device technologies due to the unique nature of boron–boron bonds. To realize its full potential, borophene needs to be seamlessly interfaced with other materials, thus motivating the atomic-scale characterization of borophene-based heterostructures. Here, we report the vertical integration of borophene with tetraphenyldibenzoperiflanthene (DBP) and measure the angstrom-scale interfacial interactions with ultrahigh-vacuum tip-enhanced Raman spectroscopy (UHV-TERS). In addition to identifying the vibrational signatures of adsorbed DBP, TERS reveals subtle ripples and compressive strains of the borophene lattice underneath the molecular layer. The induced interfacial strain is demonstrated to extend in borophene by ～1 nm beyond the molecular region by virtue of 5 chemical spatial resolution. Molecular manipulation experiments prove the molecular origins of interfacial strain in addition to allowing atomic control of local strain with magnitudes as small as ～0.6%. In addition to being the first realization of an organic/borophene vertical heterostructure, this study demonstrates that UHV-TERS is a powerful analytical tool to spectroscopically investigate buried and highly localized interfacial characteristics at the atomic scale, which can be applied to additional classes of heterostructured materials.

DOI: 10.1021/jacs.1c04380

Source: https://pubs.acs.org/doi/10.1021/jacs.1c04380