Sun Xin, Lu Zonghuan, Xiang Yu, Wang Yiping, Shi Jian, Wang Gwo-Ching, Washington Morris A, Lu Toh-Ming
ACS Nano. 2018 Jun 26;12(6):6100-6108. doi: 10.1021/acsnano.8b02374. Epub 2018 May 15.
Antimony (Sb) nanostructures, including islands, sheets, and thin films, of high crystallinity were epitaxially grown on single-crystalline graphene through van der Waals interactions. Two types of graphene substrates grown by chemical vapor deposition were used, the as-grown graphene on Cu(111)/ c-sapphire and the transferred graphene on SiO/Si. On the as-grown graphene, deposition of ultrathin Sb resulted in two growth modes and associated morphologies of Sb. One was Sb islands grown in Volmer-Weber (VW) mode, and the other was Sb sheets grown in Frank-van der Merve (FM) mode. In contrast, only Sb islands grown in VW mode were found in a parallel growth experiment on the transferred graphene. The existence of Sb sheets on the as-grown graphene was attributed to the remote epitaxy between Sb and Cu underneath the graphene. In addition, Sb thin films were grown on both the as-grown and transferred graphene substrates. Both films indicated high quality, and no significant difference can be found between these two films. This work unveiled two epitaxial alignments between Sb(0001) and graphene, namely, Sb [101̅0]∥graphene [10] for Sb islands and Sb [21̅1̅0]∥graphene [10] for Sb sheets. For Sb thin films on graphene, the epitaxial alignment followed that of Sb islands, implying that Sb thin films originated from the continued growth of Sb islands. Last, Raman spectroscopy was used to probe the state of graphene under ultrathin Sb. No strain, doping, or disorder was found in the graphene postgrowth of Sb. The knowledge of the interface formation between ultrathin Sb and graphene provides a valuable foundation for future research on van der Waals heterostructures between antimonene and graphene.
通过范德华相互作用，在单晶石墨烯上外延生长出了具有高结晶度的锑（Sb）纳米结构，包括岛状、片状和薄膜状。使用了两种通过化学气相沉积生长的石墨烯基底，即生长在Cu(111)/c-蓝宝石上的原位生长石墨烯以及生长在SiO/Si上的转移石墨烯。在原位生长的石墨烯上，超薄锑的沉积导致了两种生长模式以及与之相关的锑的形貌。一种是在伏尔默-韦伯（VW）模式下生长的锑岛，另一种是在弗兰克-范德梅尔（FM）模式下生长的锑片。相比之下，在转移石墨烯上的平行生长实验中，只发现了以VW模式生长的锑岛。原位生长的石墨烯上存在锑片归因于石墨烯下方的锑与铜之间的远程外延。此外，在原位生长和转移的石墨烯基底上都生长了锑薄膜。两种薄膜都显示出高质量，并且这两种薄膜之间没有发现显著差异。这项工作揭示了Sb(0001)与石墨烯之间的两种外延排列方式，即对于锑岛而言是Sb [101̅0]∥石墨烯 [10]，对于锑片而言是Sb [21̅1̅0]∥石墨烯 [10]。对于石墨烯上的锑薄膜，外延排列遵循锑岛的排列方式，这意味着锑薄膜源自锑岛的持续生长。最后，使用拉曼光谱来探测超薄锑下石墨烯的状态。在锑生长后的石墨烯中未发现应变、掺杂或无序现象。超薄锑与石墨烯之间界面形成的相关知识为未来关于锑烯与石墨烯之间范德华异质结构的研究提供了有价值的基础。
