120 likes | 358 Vues
Nano-indentation of Graphene Sheet using Molecular Dynamic Simulation. Roy Downs University of Arkansas Faculty Mentor: Joe Rencis Graduate Student Mentor: Sachin Terdalkar. Graphene Sheet. Monolayer Structure of Carbon Atoms Hexagonal Shape Lattice Characteristics Very Strong
E N D
Nano-indentation of Graphene Sheet using Molecular Dynamic Simulation Roy Downs University of Arkansas Faculty Mentor: Joe Rencis Graduate Student Mentor: Sachin Terdalkar
Graphene Sheet • Monolayer Structure of Carbon Atoms • Hexagonal Shape Lattice • Characteristics • Very Strong • Highly Conductive • High Opacity http://en.wikipedia.org/wiki/File:Graphene_xyz.jpg
Potential Applications • Nano-scale Electronics • Ultracapacitors • Pressure Sensors • Nano Resonators Graphene Transistor [Freitag, M., Nature Nanotechnology 2008]
Experimental Measurement of Mechanical Properties • Mechanical Properties: Project Focus • Young’s Modulus (measured E=1.0 TPa) • Intrinsic Strength (measured sint=130 GPa) Graphene Sheet Silicon Substrate Silicon Substrate Graphene Sheet Graphene on Silicon Substrate Atomic Force Microscope (AFM) http://www.sciencemag.org/ http://www3.physik.uni-greifswald.de/method/afm/eafm.htm
Load – Indentation Curve d Graphene Sheet & AFM Indenter http://www.physorg.com/news135959004.html http://www.sciencemag.org/
Molecular Dynamics Simulation • Atoms are assumed lumped point masses • Interaction through Inter-atomic Potential • Atomic position from numerical integration of equations of motion http://en.wikipedia.org/wiki/File:Argon_dimer_potential_and_Lennard-Jones.png F = ma
Goals • Using MD Simulations • Generate load-indentation curve • Determine Young’s Modulus • Calculate Intrinsic Strength • Determine Interaction Between Si Substrate and Graphene Sheet Using MD Simulations http://www.physorg.com/news135959004.html Silicon Substrate Graphene Sheet http://www.sciencemag.org/