Ultrathin graphdiyne film on graphene through solution-phase van der Waals epitaxy

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.

Citation

Gao X, Zhu Y, Yi D, Zhou J, Zhang S, et al. (2018) Ultrathin graphdiyne film on graphene through solution-phase van der Waals epitaxy. Science Advances 4: eaat6378. Available: http://dx.doi.org/10.1126/sciadv.aat6378.

Acknowledgements

Y.Z. acknowledges financial support from the Thousand Talents Program for Distinguished Young Scholars and National Natural Science Foundation of China (21771161). This work was supported by the Ministry of Science and Technology of China (2016YFA0200101 and 2016YFA0200104), the National Natural Science Foundation of China (grant nos. 51432002, 51720105003, and 21790052), the Beijing Municipal Science and Technology Project (grant no. Z161100002116026), and the Institute for Basic Science (IBS-R019-D1) of South Korea.