Assembling inorganic nanomaterials on graphene1-3 is of interest in the development of nanodevices and nanocomposite materials, and the ability to align such inorganic nanomaterials on the graphene surface is expected to lead to improved functionalities4, as has previously been demonstrated with organic nanomaterials epitaxially aligned on graphitic surfaces5-10. However, because graphene is chemically inert, it is difficult to precisely assemble inorganic nanomaterials on pristine graphene2,11-16. Previous techniques2,3 based on dangling bonds of damaged graphene11,17-20, intermediate seed materials11,15,16,21,22 and vapour-phase deposition at high temperature12-14,23-15, have only formed randomly oriented or poorly aligned inorganic nanostructures. Here, we show that inorganic nanowires of gold(I) cyanide can grow directly on pristine graphene, aligning themselves with the zigzag lattice directions of the graphene. The nanowires are synthesized through a self-organized growth process in aqueous solution at room temperature, which indicates that the inorganic material spontaneously binds to the pristine graphene surface. First-principles calculations suggest that this assembly originates from lattice matching and π interaction to gold atoms. Using the synthesized nanowires as templates, we also fabricate nanostructures with controlled crystal orientations such as graphene nanoribbons with zigzag-edged directions.
Bibliographical noteFunding Information:
The authors thank A.P. Alivisatos, H. Fujita, Y. Arakawa, B.J. Kim, L. Yang, J. Moon, Y. Ota, H. Suh, J. Kwon and J. Min for helpful discussions. The authors also thank J. Kim and Y. Mizutani for the AFM analysis, S. Mori and M. Onuki for technical support and A. Sato for help with graphic illustrations. This work was mainly supported by the Takeuchi Biohybrid Innovation Project, Exploratory Research for Advanced Technology (ERATO), Japan Science and Technology (JST). A.Z. and K.K. acknowledge support from the Director, Office of Energy Research, Materials Sciences and Engineering Division, of the US Department of Energy (DE-AC02-05CH11231) and from the Office of Naval Research (MURI grant N00014-09-1066). K.K. also acknowledges support from the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2014R1A1A2058178). D.A.W. and J.P. acknowledge support from the Harvard MRSEC (DMR-0820484) and Amore-Pacific. H.L. and J.K. acknowledge support from the Basic Science Research Program through the National Research Foundation of Korea, funded by the Ministry of Science, ICT & Future Planning (NRF-2015R1A1A1001583) and also acknowledge support from KISTI under the Supercomputing Applications Support Program (KSC-2013-C3-034). H.Y.J. acknowledges support from the 2012 Research Fund (1.120032.01) of UNIST.
All Science Journal Classification (ASJC) codes
- Atomic and Molecular Physics, and Optics
- Biomedical Engineering
- Materials Science(all)
- Condensed Matter Physics
- Electrical and Electronic Engineering