Nanoscale Silicon as a Catalyst for Graphene Growth: Mechanistic Insight from in Situ Raman Spectroscopy
- Vanderbilt Univ., Nashville, TN (United States)
- Air Force Research Lab. (AFRL), Wright-Patterson AFB, OH (United States)
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Science (CNMS)
Nanoscale carbons are typically synthesized by thermal decomposition of a hydrocarbon at the surface of a metal catalyst. Whereas the use of silicon as an alternative to metal catalysts could unlock new techniques to seamlessly couple carbon nanostructures and semiconductor materials, stable carbide formation renders bulk silicon incapable of the precipitation and growth of graphitic structures. In this article, we provide evidence supported by comprehensive in situ Raman experiments that indicates nanoscale grains of silicon in porous silicon (PSi) scaffolds act as catalysts for hydrocarbon decomposition and growth of few-layered graphene at temperatures as low as 700 K. Self-limiting growth kinetics of graphene with activation energies measured between 0.32–0.37 eV elucidates the formation of highly reactive surface-bound Si radicals that aid in the decomposition of hydrocarbons. Nucleation and growth of graphitic layers on PSi exhibits striking similarity to catalytic growth on nickel surfaces, involving temperature dependent surface and subsurface diffusion of carbon. Lastly, this work elucidates how the nanoscale properties of silicon can be exploited to yield catalytic properties distinguished from bulk silicon, opening an important avenue to engineer catalytic interfaces combining the two most technologically important materials for modern applications—silicon and nanoscale carbons.
- Research Organization:
- Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Sciences (CNMS)
- Sponsoring Organization:
- USDOE Office of Science (SC)
- Grant/Contract Number:
- AC05-00OR22725
- OSTI ID:
- 1271889
- Journal Information:
- Journal of Physical Chemistry. C, Vol. 120, Issue 26; ISSN 1932-7447
- Publisher:
- American Chemical SocietyCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Web of Science
Thermally Carbonized Porous Silicon and Its Recent Applications
|
journal | February 2018 |
Graphene on Group‐IV Elementary Semiconductors: The Direct Growth Approach and Its Applications
|
journal | February 2019 |
Similar Records
Simulation of the Dynamics of Isothermal Growth of Single-Layer Graphene on a Copper Catalyst in the Process of Chemical Vapor Deposition of Hydrocarbons
Solid-state graphene formation via a nickel carbide intermediate phase [Nickel carbide (Ni3C) as an intermediate phase for graphene formation]