Abstract
The distributions of sizes of silver nanoparticles that were deposited on monolayer, bilayer, and trilayer graphene films were observed. Deposition was carried out by thermal evaporation and the graphene films, placed on SiO2/Si substrates, were obtained by the mechanical splitting of graphite. Before the deposition, optical microscopy and Raman spectroscopy were utilized to identify the number of the graphene layers. After the deposition, scanning electron microscopy was used to observe the morphologies of the particles. Systematic analysis revealed that the average sizes of the nanoparticles increased with the number of graphene layers. The density of nanoparticles decreased as the number of graphene layers increased, revealing a large variation in the surface diffusion strength of nanoparticles on the different substrates. The mechanisms of formation of these layer-dependent morphologies of silver on n-layer graphene are related to the surface free energy and surface diffusion of the n-layer graphene. The effect of the substrate such as SiO2/Si was investigated by fabricating suspended graphene, and the size and density were similar to those of supported graphene. Based on a comparison of the results, the different morphologies of the silver nanoparticles on different graphene layers were theorized to be caused only by the variation of the diffusion barriers with the number of layers of graphene.
Highlights
IntroductionIt has various unique electrical and optical properties of interest to scientists and technologists [1,2,3]
A single atomic layer of graphene is the thinnest sp2 allotrope of carbon
Silver nanoparticles were deposited on graphene flakes at a rate of 0.5 nm/min using a thermal deposition system to a thickness of 5 nm at a fixed temperature of the deposition system of 300 K
Summary
It has various unique electrical and optical properties of interest to scientists and technologists [1,2,3]. Graphene samples are widely fabricated by the micromechanical cleavage of highly oriented pyrolytic graphite (HOPG) with scotch tape. Layers of oxides such as SiO2 and Al2O3 with special thickness between graphene and the substrate are typically used to make graphene optically visible [4,5,6,7]. Raman and surfaceenhanced Raman spectroscopy have been widely utilized to elucidate the vibration properties of materials [9,10,11,12,13,14]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
