RT Journal Article SR Electronic T1 Ultrathin graphdiyne film on graphene through solution-phase van der Waals epitaxy JF Science Advances JO Sci Adv FD American Association for the Advancement of Science SP eaat6378 DO 10.1126/sciadv.aat6378 VO 4 IS 7 A1 Gao, Xin A1 Zhu, Yihan A1 Yi, Ding A1 Zhou, Jingyuan A1 Zhang, Shishu A1 Yin, Chen A1 Ding, Feng A1 Zhang, Shuqing A1 Yi, Xiaohui A1 Wang, Jizheng A1 Tong, Lianming A1 Han, Yu A1 Liu, Zhongfan A1 Zhang, Jin YR 2018 UL http://advances.sciencemag.org/content/4/7/eaat6378.abstract AB Graphdiyne (GDY) is an ordered two-dimensional (2D) carbon allotrope comprising sp- and sp2-hybridized carbon atoms with high degrees of π-conjugation, which features a natural band gap and superior electric properties. However, the synthesis of one- or few-layer GDY remains challenging because of the free rotation around alkyne-aryl single bonds and the lack of thickness control. We report the facile synthesis of an ultrathin single-crystalline GDY film on graphene through a solution-phase van der Waals epitaxial strategy. The weak admolecule-substrate interaction at the heterojunction drastically relaxes the large lattice mismatch between GDY and graphene. It allows the fast in-plane coupling of admolecules and slow out-of-plane growth toward the formation of an incommensurately stacked heterostructure, which is composed of single-layer graphene and few-layer ABC-stacked GDY, as directly observed by electron microscopy and identified from Raman fingerprints. This study provides a general route not only to the bottom-up synthesis of intriguing 2D acetylenic carbon allotropes but also to the device fabrication for the direct measurement of their intrinsic electrical, mechanical, and thermal properties.